mirror of https://github.com/torvalds/linux.git
867 Commits
| Author | SHA1 | Message | Date |
|---|---|---|---|
Jacob Pan
|
43650dcf6d |
x86/irq: Set up per host CPU posted interrupt descriptors
To support posted MSIs, create a posted interrupt descriptor (PID) for each host CPU. Later on, when setting up interrupt affinity, the IOMMU's interrupt remapping table entry (IRTE) will point to the physical address of the matching CPU's PID. Each PID is initialized with the owner CPU's physical APICID as the destination. Originally-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20240423174114.526704-7-jacob.jun.pan@linux.intel.com |
|
Tony Luck
|
b24e466abf |
x86/bugs: Switch to new Intel CPU model defines
New CPU #defines encode vendor and family as well as model. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lore.kernel.org/r/20240424181507.41693-1-tony.luck@intel.com |
|
Ingo Molnar
|
21f546a43a |
Merge branch 'x86/urgent' into x86/cpu, to resolve conflict
There's a new conflict between this commit pending in x86/cpu: |
|
|
Ingo Molnar
|
d0485730d2 |
x86/bugs: Rename various 'ia32_cap' variables to 'x86_arch_cap_msr'
So we are using the 'ia32_cap' value in a number of places, which got its name from MSR_IA32_ARCH_CAPABILITIES MSR register. But there's very little 'IA32' about it - this isn't 32-bit only code, nor does it originate from there, it's just a historic quirk that many Intel MSR names are prefixed with IA32_. This is already clear from the helper method around the MSR: x86_read_arch_cap_msr(), which doesn't have the IA32 prefix. So rename 'ia32_cap' to 'x86_arch_cap_msr' to be consistent with its role and with the naming of the helper function. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Nikolay Borisov <nik.borisov@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/9592a18a814368e75f8f4b9d74d3883aa4fd1eaf.1712813475.git.jpoimboe@kernel.org |
|
|
Ingo Molnar
|
0e6ebfd163 |
Linux 6.9-rc3
-----BEGIN PGP SIGNATURE----- iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAmYTAJYeHHRvcnZhbGRz QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiG2bEH/jOBXd0ZCz+s9+F4 TbSvDEE8UjitQdEJ5WSBY9CEvFI8OuVQr23gYPUn+gfgqLX0Vsp8HfxL6bBP5Tj6 DSzAkwF/mvIfa6VLFmO1GmvyhYtmWkmbM825tNqKHSNTBc9cCLH3H+780wNtTMwQ VkB8O3KS/wZBGKSbFfiXW+fT3SkWIMLtdBAaox+vcxHXpiluXxSbxANRD5kTbdG0 UAW9S4+3A0jNk/KeXEvJDqkf7C3ASsjtNPbK+gFDfOXxdNYFTC2IUf93rL61VB4s C2rtUklcLE8gFDtvkQ8JtGWmDj4pWPEDIyhICKlzP/aKCjXcNzLaoM0GJQYJS+PN aNevw24= =318J -----END PGP SIGNATURE----- Merge tag 'v6.9-rc3' into x86/cpu, to pick up fixes Signed-off-by: Ingo Molnar <mingo@kernel.org> |
|
Pawan Gupta
|
be482ff950 |
x86/bhi: Enumerate Branch History Injection (BHI) bug
Mitigation for BHI is selected based on the bug enumeration. Add bits needed to enumerate BHI bug. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> |
|
Thomas Gleixner
|
c90399fbd7 |
x86/cpu: Ensure that CPU info updates are propagated on UP
The boot sequence evaluates CPUID information twice:
1) During early boot
2) When finalizing the early setup right before
mitigations are selected and alternatives are patched.
In both cases the evaluation is stored in boot_cpu_data, but on UP the
copying of boot_cpu_data to the per CPU info of the boot CPU happens
between #1 and #2. So any update which happens in #2 is never propagated to
the per CPU info instance.
Consolidate the whole logic and copy boot_cpu_data right before applying
alternatives as that's the point where boot_cpu_data is in it's final
state and not supposed to change anymore.
This also removes the voodoo mb() from smp_prepare_cpus_common() which
had absolutely no purpose.
Fixes:
|
|
Borislav Petkov (AMD)
|
95bfb35269 |
x86/cpu: Get rid of an unnecessary local variable in get_cpu_address_sizes()
Drop 'vp_bits_from_cpuid' as it is not really needed. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20240316120706.4352-1-bp@alien8.de |
|
Linus Torvalds
|
0e33cf955f |
* Mitigate RFDS vulnerability
-----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEV76QKkVc4xCGURexaDWVMHDJkrAFAmXvZgoACgkQaDWVMHDJ krC2Eg//aZKBp97/DSzRqXKDwJzVUr0sGJ9cii0gVT1sI+1U6ZZCh/roVH4xOT5/ HqtOOnQ+X0mwUx2VG3Yv2VPI7VW68sJ3/y9D8R4tnMEsyQ4CmDw96Pre3NyKr/Av jmW7SK94fOkpNFJOMk3zpk7GtRUlCsVkS1P61dOmMYduguhel/V20rWlx83BgnAY Rf/c3rBjqe8Ri3rzBP5icY/d6OgwoafuhME31DD/j6oKOh+EoQBvA4urj46yMTMX /mrK7hCm/wqwuOOvgGbo7sfZNBLCYy3SZ3EyF4beDERhPF1DaSvCwOULpGVJroqu SelFsKXAtEbYrDgsan+MYlx3bQv43q7PbHska1gjkH91plO4nAsssPr5VsusUKmT sq8jyBaauZb40oLOSgooL4RqAHrfs8q5695Ouwh/DB/XovMezUI1N/BkpGFmqpJI o2xH9P5q520pkB8pFhN9TbRuFSGe/dbWC24QTq1DUajo3M3RwcwX6ua9hoAKLtDF pCV5DNcVcXHD3Cxp0M5dQ5JEAiCnW+ZpUWgxPQamGDNW5PEvjDmFwql2uWw/qOuW lkheOIffq8ejUBQFbN8VXfIzzeeKQNFiIcViaqGITjIwhqdHAzVi28OuIGwtdh3g ywLzSC8yvyzgKrNBgtFMr3ucKN0FoPxpBro253xt2H7w8srXW64= =5V9t -----END PGP SIGNATURE----- Merge tag 'rfds-for-linus-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 RFDS mitigation from Dave Hansen: "RFDS is a CPU vulnerability that may allow a malicious userspace to infer stale register values from kernel space. Kernel registers can have all kinds of secrets in them so the mitigation is basically to wait until the kernel is about to return to userspace and has user values in the registers. At that point there is little chance of kernel secrets ending up in the registers and the microarchitectural state can be cleared. This leverages some recent robustness fixes for the existing MDS vulnerability. Both MDS and RFDS use the VERW instruction for mitigation" * tag 'rfds-for-linus-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: KVM/x86: Export RFDS_NO and RFDS_CLEAR to guests x86/rfds: Mitigate Register File Data Sampling (RFDS) Documentation/hw-vuln: Add documentation for RFDS x86/mmio: Disable KVM mitigation when X86_FEATURE_CLEAR_CPU_BUF is set |
|
|
Linus Torvalds
|
685d982112 |
Core x86 changes for v6.9:
- The biggest change is the rework of the percpu code,
to support the 'Named Address Spaces' GCC feature,
by Uros Bizjak:
- This allows C code to access GS and FS segment relative
memory via variables declared with such attributes,
which allows the compiler to better optimize those accesses
than the previous inline assembly code.
- The series also includes a number of micro-optimizations
for various percpu access methods, plus a number of
cleanups of %gs accesses in assembly code.
- These changes have been exposed to linux-next testing for
the last ~5 months, with no known regressions in this area.
- Fix/clean up __switch_to()'s broken but accidentally
working handling of FPU switching - which also generates
better code.
- Propagate more RIP-relative addressing in assembly code,
to generate slightly better code.
- Rework the CPU mitigations Kconfig space to be less idiosyncratic,
to make it easier for distros to follow & maintain these options.
- Rework the x86 idle code to cure RCU violations and
to clean up the logic.
- Clean up the vDSO Makefile logic.
- Misc cleanups and fixes.
[ Please note that there's a higher number of merge commits in
this branch (three) than is usual in x86 topic trees. This happened
due to the long testing lifecycle of the percpu changes that
involved 3 merge windows, which generated a longer history
and various interactions with other core x86 changes that we
felt better about to carry in a single branch. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=3v4F
-----END PGP SIGNATURE-----
Merge tag 'x86-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core x86 updates from Ingo Molnar:
- The biggest change is the rework of the percpu code, to support the
'Named Address Spaces' GCC feature, by Uros Bizjak:
- This allows C code to access GS and FS segment relative memory
via variables declared with such attributes, which allows the
compiler to better optimize those accesses than the previous
inline assembly code.
- The series also includes a number of micro-optimizations for
various percpu access methods, plus a number of cleanups of %gs
accesses in assembly code.
- These changes have been exposed to linux-next testing for the
last ~5 months, with no known regressions in this area.
- Fix/clean up __switch_to()'s broken but accidentally working handling
of FPU switching - which also generates better code
- Propagate more RIP-relative addressing in assembly code, to generate
slightly better code
- Rework the CPU mitigations Kconfig space to be less idiosyncratic, to
make it easier for distros to follow & maintain these options
- Rework the x86 idle code to cure RCU violations and to clean up the
logic
- Clean up the vDSO Makefile logic
- Misc cleanups and fixes
* tag 'x86-core-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
x86/idle: Select idle routine only once
x86/idle: Let prefer_mwait_c1_over_halt() return bool
x86/idle: Cleanup idle_setup()
x86/idle: Clean up idle selection
x86/idle: Sanitize X86_BUG_AMD_E400 handling
sched/idle: Conditionally handle tick broadcast in default_idle_call()
x86: Increase brk randomness entropy for 64-bit systems
x86/vdso: Move vDSO to mmap region
x86/vdso/kbuild: Group non-standard build attributes and primary object file rules together
x86/vdso: Fix rethunk patching for vdso-image-{32,64}.o
x86/retpoline: Ensure default return thunk isn't used at runtime
x86/vdso: Use CONFIG_COMPAT_32 to specify vdso32
x86/vdso: Use $(addprefix ) instead of $(foreach )
x86/vdso: Simplify obj-y addition
x86/vdso: Consolidate targets and clean-files
x86/bugs: Rename CONFIG_RETHUNK => CONFIG_MITIGATION_RETHUNK
x86/bugs: Rename CONFIG_CPU_SRSO => CONFIG_MITIGATION_SRSO
x86/bugs: Rename CONFIG_CPU_IBRS_ENTRY => CONFIG_MITIGATION_IBRS_ENTRY
x86/bugs: Rename CONFIG_CPU_UNRET_ENTRY => CONFIG_MITIGATION_UNRET_ENTRY
x86/bugs: Rename CONFIG_SLS => CONFIG_MITIGATION_SLS
...
|
|
|
Linus Torvalds
|
fcc196579a |
Misc cleanups, including a large series from Thomas Gleixner to
cure Sparse warnings. Signed-off-by: Ingo Molnar <mingo@kernel.org> -----BEGIN PGP SIGNATURE----- iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmXvAFQRHG1pbmdvQGtl cm5lbC5vcmcACgkQEnMQ0APhK1hkDRAAwASVCQ88kiGqNQtHibXlK54mAFGsc0xv T8OPds15DUzoLg/y8lw0X0DHly6MdGXVmygybejNIw2BN4lhLjQ7f4Ria7rv7LDy FcI1jfvysEMyYRFHGRefb/GBFzuEfKoROwf+QylGmKz0ZK674gNMngsI9pwOBdbe wElq3IkHoNuTUfH9QA4BvqGam1n122nvVTop3g0PMHWzx9ky8hd/BEUjXFZhfINL zZk3fwUbER2QYbhHt+BN2GRbdf2BrKvqTkXpKxyXTdnpiqAo0CzBGKerZ62H82qG n737Nib1lrsfM5yDHySnau02aamRXaGvCJUd6gpac1ZmNpZMWhEOT/0Tr/Nj5ztF lUAvKqMZn/CwwQky1/XxD0LHegnve0G+syqQt/7x7o1ELdiwTzOWMCx016UeodzB yyHf3Xx9J8nt3snlrlZBaGEfegg9ePLu5Vir7iXjg3vrloUW8A+GZM62NVxF4HVV QWF80BfWf8zbLQ/OS1382t1shaioIe5pEXzIjcnyVIZCiiP2/5kP2O6P4XVbwVlo Ca5eEt8U1rtsLUZaCzI2ZRTQf/8SLMQWyaV+ZmkVwcVdFoARC31EgdE5wYYoZOf6 7Vl+rXd+rZCuTWk0ZgznCZEm75aaqukaQCBa2V8hIVociLFVzhg/Tjedv7s0CspA hNfxdN1LDZc= =0eJ7 -----END PGP SIGNATURE----- Merge tag 'x86-cleanups-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Ingo Molnar: "Misc cleanups, including a large series from Thomas Gleixner to cure sparse warnings" * tag 'x86-cleanups-2024-03-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/nmi: Drop unused declaration of proc_nmi_enabled() x86/callthunks: Use EXPORT_PER_CPU_SYMBOL_GPL() for per CPU variables x86/cpu: Provide a declaration for itlb_multihit_kvm_mitigation x86/cpu: Use EXPORT_PER_CPU_SYMBOL_GPL() for x86_spec_ctrl_current x86/uaccess: Add missing __force to casts in __access_ok() and valid_user_address() x86/percpu: Cure per CPU madness on UP smp: Consolidate smp_prepare_boot_cpu() x86/msr: Add missing __percpu annotations x86/msr: Prepare for including <linux/percpu.h> into <asm/msr.h> perf/x86/amd/uncore: Fix __percpu annotation x86/nmi: Remove an unnecessary IS_ENABLED(CONFIG_SMP) x86/apm_32: Remove dead function apm_get_battery_status() x86/insn-eval: Fix function param name in get_eff_addr_sib() |
|
|
Linus Torvalds
|
38b334fc76 |
- Add the x86 part of the SEV-SNP host support. This will allow the
kernel to be used as a KVM hypervisor capable of running SNP (Secure Nested Paging) guests. Roughly speaking, SEV-SNP is the ultimate goal of the AMD confidential computing side, providing the most comprehensive confidential computing environment up to date. This is the x86 part and there is a KVM part which did not get ready in time for the merge window so latter will be forthcoming in the next cycle. - Rework the early code's position-dependent SEV variable references in order to allow building the kernel with clang and -fPIE/-fPIC and -mcmodel=kernel - The usual set of fixes, cleanups and improvements all over the place -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmXvH0wACgkQEsHwGGHe VUrzmA//VS/n6dhHRnm/nAGngr4PeegkgV1OhyKYFfiZ272rT6P9QvblQrgcY0dc Ij1DOhEKlke51pTHvMOQ33B3P4Fuc0mx3dpCLY0up5V26kzQiKCjRKEkC4U1bcw8 W4GqMejaR89bE14bYibmwpSib9T/uVsV65eM3xf1iF5UvsnoUaTziymDoy+nb43a B1pdd5vcl4mBNqXeEvt0qjg+xkMLpWUI9tJDB8mbMl/cnIFGgMZzBaY8oktHSROK QpuUnKegOgp1RXpfLbNjmZ2Q4Rkk4MNazzDzWq3EIxaRjXL3Qp507ePK7yeA2qa0 J3jCBQc9E2j7lfrIkUgNIzOWhMAXM2YH5bvH6UrIcMi1qsWJYDmkp2MF1nUedjdf Wj16/pJbeEw1aKKIywJGwsmViSQju158vY3SzXG83U/A/Iz7zZRHFmC/ALoxZptY Bi7VhfcOSpz98PE3axnG8CvvxRDWMfzBr2FY1VmQbg6VBNo1Xl1aP/IH1I8iQNKg /laBYl/qP+1286TygF1lthYROb1lfEIJprgi2xfO6jVYUqPb7/zq2sm78qZRfm7l 25PN/oHnuidfVfI/H3hzcGubjOG9Zwra8WWYBB2EEmelf21rT0OLqq+eS4T6pxFb GNVfc0AzG77UmqbrpkAMuPqL7LrGaSee4NdU3hkEdSphlx1/YTo= =c1ps -----END PGP SIGNATURE----- Merge tag 'x86_sev_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 SEV updates from Borislav Petkov: - Add the x86 part of the SEV-SNP host support. This will allow the kernel to be used as a KVM hypervisor capable of running SNP (Secure Nested Paging) guests. Roughly speaking, SEV-SNP is the ultimate goal of the AMD confidential computing side, providing the most comprehensive confidential computing environment up to date. This is the x86 part and there is a KVM part which did not get ready in time for the merge window so latter will be forthcoming in the next cycle. - Rework the early code's position-dependent SEV variable references in order to allow building the kernel with clang and -fPIE/-fPIC and -mcmodel=kernel - The usual set of fixes, cleanups and improvements all over the place * tag 'x86_sev_for_v6.9_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) x86/sev: Disable KMSAN for memory encryption TUs x86/sev: Dump SEV_STATUS crypto: ccp - Have it depend on AMD_IOMMU iommu/amd: Fix failure return from snp_lookup_rmpentry() x86/sev: Fix position dependent variable references in startup code crypto: ccp: Make snp_range_list static x86/Kconfig: Remove CONFIG_AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT Documentation: virt: Fix up pre-formatted text block for SEV ioctls crypto: ccp: Add the SNP_SET_CONFIG command crypto: ccp: Add the SNP_COMMIT command crypto: ccp: Add the SNP_PLATFORM_STATUS command x86/cpufeatures: Enable/unmask SEV-SNP CPU feature KVM: SEV: Make AVIC backing, VMSA and VMCB memory allocation SNP safe crypto: ccp: Add panic notifier for SEV/SNP firmware shutdown on kdump iommu/amd: Clean up RMP entries for IOMMU pages during SNP shutdown crypto: ccp: Handle legacy SEV commands when SNP is enabled crypto: ccp: Handle non-volatile INIT_EX data when SNP is enabled crypto: ccp: Handle the legacy TMR allocation when SNP is enabled x86/sev: Introduce an SNP leaked pages list crypto: ccp: Provide an API to issue SEV and SNP commands ... |
|
|
Linus Torvalds
|
720c857907 |
Support for x86 Fast Return and Event Delivery (FRED):
FRED is a replacement for IDT event delivery on x86 and addresses most of
the technical nightmares which IDT exposes:
1) Exception cause registers like CR2 need to be manually preserved in
nested exception scenarios.
2) Hardware interrupt stack switching is suboptimal for nested exceptions
as the interrupt stack mechanism rewinds the stack on each entry which
requires a massive effort in the low level entry of #NMI code to handle
this.
3) No hardware distinction between entry from kernel or from user which
makes establishing kernel context more complex than it needs to be
especially for unconditionally nestable exceptions like NMI.
4) NMI nesting caused by IRET unconditionally reenabling NMIs, which is a
problem when the perf NMI takes a fault when collecting a stack trace.
5) Partial restore of ESP when returning to a 16-bit segment
6) Limitation of the vector space which can cause vector exhaustion on
large systems.
7) Inability to differentiate NMI sources
FRED addresses these shortcomings by:
1) An extended exception stack frame which the CPU uses to save exception
cause registers. This ensures that the meta information for each
exception is preserved on stack and avoids the extra complexity of
preserving it in software.
2) Hardware interrupt stack switching is non-rewinding if a nested
exception uses the currently interrupt stack.
3) The entry points for kernel and user context are separate and GS BASE
handling which is required to establish kernel context for per CPU
variable access is done in hardware.
4) NMIs are now nesting protected. They are only reenabled on the return
from NMI.
5) FRED guarantees full restore of ESP
6) FRED does not put a limitation on the vector space by design because it
uses a central entry points for kernel and user space and the CPUstores
the entry type (exception, trap, interrupt, syscall) on the entry stack
along with the vector number. The entry code has to demultiplex this
information, but this removes the vector space restriction.
The first hardware implementations will still have the current
restricted vector space because lifting this limitation requires
further changes to the local APIC.
7) FRED stores the vector number and meta information on stack which
allows having more than one NMI vector in future hardware when the
required local APIC changes are in place.
The series implements the initial FRED support by:
- Reworking the existing entry and IDT handling infrastructure to
accomodate for the alternative entry mechanism.
- Expanding the stack frame to accomodate for the extra 16 bytes FRED
requires to store context and meta information
- Providing FRED specific C entry points for events which have information
pushed to the extended stack frame, e.g. #PF and #DB.
- Providing FRED specific C entry points for #NMI and #MCE
- Implementing the FRED specific ASM entry points and the C code to
demultiplex the events
- Providing detection and initialization mechanisms and the necessary
tweaks in context switching, GS BASE handling etc.
The FRED integration aims for maximum code reuse vs. the existing IDT
implementation to the extent possible and the deviation in hot paths like
context switching are handled with alternatives to minimalize the
impact. The low level entry and exit paths are seperate due to the extended
stack frame and the hardware based GS BASE swichting and therefore have no
impact on IDT based systems.
It has been extensively tested on existing systems and on the FRED
simulation and as of now there are know outstanding problems.
-----BEGIN PGP SIGNATURE-----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=Ib7w
-----END PGP SIGNATURE-----
Merge tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 FRED support from Thomas Gleixner:
"Support for x86 Fast Return and Event Delivery (FRED).
FRED is a replacement for IDT event delivery on x86 and addresses most
of the technical nightmares which IDT exposes:
1) Exception cause registers like CR2 need to be manually preserved
in nested exception scenarios.
2) Hardware interrupt stack switching is suboptimal for nested
exceptions as the interrupt stack mechanism rewinds the stack on
each entry which requires a massive effort in the low level entry
of #NMI code to handle this.
3) No hardware distinction between entry from kernel or from user
which makes establishing kernel context more complex than it needs
to be especially for unconditionally nestable exceptions like NMI.
4) NMI nesting caused by IRET unconditionally reenabling NMIs, which
is a problem when the perf NMI takes a fault when collecting a
stack trace.
5) Partial restore of ESP when returning to a 16-bit segment
6) Limitation of the vector space which can cause vector exhaustion
on large systems.
7) Inability to differentiate NMI sources
FRED addresses these shortcomings by:
1) An extended exception stack frame which the CPU uses to save
exception cause registers. This ensures that the meta information
for each exception is preserved on stack and avoids the extra
complexity of preserving it in software.
2) Hardware interrupt stack switching is non-rewinding if a nested
exception uses the currently interrupt stack.
3) The entry points for kernel and user context are separate and GS
BASE handling which is required to establish kernel context for
per CPU variable access is done in hardware.
4) NMIs are now nesting protected. They are only reenabled on the
return from NMI.
5) FRED guarantees full restore of ESP
6) FRED does not put a limitation on the vector space by design
because it uses a central entry points for kernel and user space
and the CPUstores the entry type (exception, trap, interrupt,
syscall) on the entry stack along with the vector number. The
entry code has to demultiplex this information, but this removes
the vector space restriction.
The first hardware implementations will still have the current
restricted vector space because lifting this limitation requires
further changes to the local APIC.
7) FRED stores the vector number and meta information on stack which
allows having more than one NMI vector in future hardware when the
required local APIC changes are in place.
The series implements the initial FRED support by:
- Reworking the existing entry and IDT handling infrastructure to
accomodate for the alternative entry mechanism.
- Expanding the stack frame to accomodate for the extra 16 bytes FRED
requires to store context and meta information
- Providing FRED specific C entry points for events which have
information pushed to the extended stack frame, e.g. #PF and #DB.
- Providing FRED specific C entry points for #NMI and #MCE
- Implementing the FRED specific ASM entry points and the C code to
demultiplex the events
- Providing detection and initialization mechanisms and the necessary
tweaks in context switching, GS BASE handling etc.
The FRED integration aims for maximum code reuse vs the existing IDT
implementation to the extent possible and the deviation in hot paths
like context switching are handled with alternatives to minimalize the
impact. The low level entry and exit paths are seperate due to the
extended stack frame and the hardware based GS BASE swichting and
therefore have no impact on IDT based systems.
It has been extensively tested on existing systems and on the FRED
simulation and as of now there are no outstanding problems"
* tag 'x86-fred-2024-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
x86/fred: Fix init_task thread stack pointer initialization
MAINTAINERS: Add a maintainer entry for FRED
x86/fred: Fix a build warning with allmodconfig due to 'inline' failing to inline properly
x86/fred: Invoke FRED initialization code to enable FRED
x86/fred: Add FRED initialization functions
x86/syscall: Split IDT syscall setup code into idt_syscall_init()
KVM: VMX: Call fred_entry_from_kvm() for IRQ/NMI handling
x86/entry: Add fred_entry_from_kvm() for VMX to handle IRQ/NMI
x86/entry/calling: Allow PUSH_AND_CLEAR_REGS being used beyond actual entry code
x86/fred: Fixup fault on ERETU by jumping to fred_entrypoint_user
x86/fred: Let ret_from_fork_asm() jmp to asm_fred_exit_user when FRED is enabled
x86/traps: Add sysvec_install() to install a system interrupt handler
x86/fred: FRED entry/exit and dispatch code
x86/fred: Add a machine check entry stub for FRED
x86/fred: Add a NMI entry stub for FRED
x86/fred: Add a debug fault entry stub for FRED
x86/idtentry: Incorporate definitions/declarations of the FRED entries
x86/fred: Make exc_page_fault() work for FRED
x86/fred: Allow single-step trap and NMI when starting a new task
x86/fred: No ESPFIX needed when FRED is enabled
...
|
|
|
Pawan Gupta
|
8076fcde01 |
x86/rfds: Mitigate Register File Data Sampling (RFDS)
RFDS is a CPU vulnerability that may allow userspace to infer kernel stale data previously used in floating point registers, vector registers and integer registers. RFDS only affects certain Intel Atom processors. Intel released a microcode update that uses VERW instruction to clear the affected CPU buffers. Unlike MDS, none of the affected cores support SMT. Add RFDS bug infrastructure and enable the VERW based mitigation by default, that clears the affected buffers just before exiting to userspace. Also add sysfs reporting and cmdline parameter "reg_file_data_sampling" to control the mitigation. For details see: Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> |
|
|
Thomas Gleixner
|
35ce64922c |
x86/idle: Select idle routine only once
The idle routine selection is done on every CPU bringup operation and has a guard in place which is effective after the first invocation, which is a pointless exercise. Invoke it once on the boot CPU and mark the related functions __init. The guard check has to stay as xen_set_default_idle() runs early. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/87edcu6vaq.ffs@tglx |
|
|
Thomas Gleixner
|
71eb4893cf |
x86/percpu: Cure per CPU madness on UP
On UP builds Sparse complains rightfully about accesses to cpu_info with per CPU accessors: cacheinfo.c:282:30: sparse: warning: incorrect type in initializer (different address spaces) cacheinfo.c:282:30: sparse: expected void const [noderef] __percpu *__vpp_verify cacheinfo.c:282:30: sparse: got unsigned int * The reason is that on UP builds cpu_info which is a per CPU variable on SMP is mapped to boot_cpu_info which is a regular variable. There is a hideous accessor cpu_data() which tries to hide this, but it's not sufficient as some places require raw accessors and generates worse code than the regular per CPU accessors. Waste sizeof(struct x86_cpuinfo) memory on UP and provide the per CPU cpu_info unconditionally. This requires to update the CPU info on the boot CPU as SMP does. (Ab)use the weakly defined smp_prepare_boot_cpu() function and implement exactly that. This allows to use regular per CPU accessors uncoditionally and paves the way to remove the cpu_data() hackery. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20240304005104.622511517@linutronix.de |
|
|
Ingo Molnar
|
9b9c280b9a |
Merge branch 'x86/urgent' into x86/apic, to resolve conflicts
Conflicts: arch/x86/kernel/cpu/common.c arch/x86/kernel/cpu/intel.c Signed-off-by: Ingo Molnar <mingo@kernel.org> |
|
Paolo Bonzini
|
9a458198eb |
x86/cpu: Allow reducing x86_phys_bits during early_identify_cpu()
In commit |
|
|
Thomas Gleixner
|
89b0f15f40 |
x86/cpu/topology: Get rid of cpuinfo::x86_max_cores
Now that __num_cores_per_package and __num_threads_per_package are available, cpuinfo::x86_max_cores and the related math all over the place can be replaced with the ready to consume data. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Link: https://lore.kernel.org/r/20240213210253.176147806@linutronix.de |
|
|
Thomas Gleixner
|
fd43b8ae76 |
x86/cpu/topology: Provide __num_[cores|threads]_per_package
Expose properly accounted information and accessors so the fiddling with other topology variables can be replaced. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Link: https://lore.kernel.org/r/20240213210253.120958987@linutronix.de |
|
|
Thomas Gleixner
|
8078f4d610 |
x86/cpu/topology: Rename smp_num_siblings
It's really a non-intuitive name. Rename it to __max_threads_per_core which is obvious. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Link: https://lore.kernel.org/r/20240213210253.011307973@linutronix.de |
|
|
Thomas Gleixner
|
380414be78 |
x86/cpu/topology: Use topology logical mapping mechanism
Replace the logical package and die management functionality and retrieve the logical IDs from the topology bitmaps. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Link: https://lore.kernel.org/r/20240213210252.901865302@linutronix.de |
|
|
Thomas Gleixner
|
090610ba70 |
x86/cpu/topology: Use topology bitmaps for sizing
Now that all possible APIC IDs are tracked in the topology bitmaps, its trivial to retrieve the real information from there. This gets rid of the guesstimates for the maximal packages and dies per package as the actual numbers can be determined before a single AP has been brought up. The number of SMT threads can now be determined correctly from the bitmaps in all situations. Up to now a system which has SMT disabled in the BIOS will still claim that it is SMT capable, because the lowest APIC ID bit is reserved for that and CPUID leaf 0xb/0x1f still enumerates the SMT domain accordingly. By calculating the bitmap weights of the SMT and the CORE domain and setting them into relation the SMT disabled in BIOS situation reports correctly that the system is not SMT capable. It also handles the situation correctly when a hybrid systems boot CPU does not have SMT as it takes the SMT capability of the APs fully into account. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Link: https://lore.kernel.org/r/20240213210252.681709880@linutronix.de |
|
|
Thomas Gleixner
|
52128a7a21 |
x86/cpu/topology: Make the APIC mismatch warnings complete
Detect all possible combinations of mismatch right in the CPUID evaluation code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Link: https://lore.kernel.org/r/20240212154638.867699078@linutronix.de |
|
|
Thomas Gleixner
|
fab75e790f |
x86/cpu: Remove x86_coreid_bits
No more users. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Zhang Rui <rui.zhang@intel.com> Tested-by: Wang Wendy <wendy.wang@intel.com> Tested-by: K Prateek Nayak <kprateek.nayak@amd.com> Link: https://lore.kernel.org/r/20240212153625.455839743@linutronix.de |
|
|
Thomas Gleixner
|
3279081dd0 |
x86/cpu: Use common topology code for HYGON
Switch it over to use the consolidated topology evaluation and remove the temporary safe guards which are not longer needed. No functional change intended. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Zhang Rui <rui.zhang@intel.com> Tested-by: Wang Wendy <wendy.wang@intel.com> Tested-by: K Prateek Nayak <kprateek.nayak@amd.com> Link: https://lore.kernel.org/r/20240212153625.207750409@linutronix.de |
|
|
Thomas Gleixner
|
22d63660c3 |
x86/cpu: Use common topology code for Intel
Intel CPUs use either topology leaf 0xb/0x1f evaluation or the legacy SMP/HT evaluation based on CPUID leaf 0x1/0x4. Move it over to the consolidated topology code and remove the random topology hacks which are sprinkled into the Intel and the common code. No functional change intended. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Zhang Rui <rui.zhang@intel.com> Tested-by: Wang Wendy <wendy.wang@intel.com> Tested-by: K Prateek Nayak <kprateek.nayak@amd.com> Link: https://lore.kernel.org/r/20240212153624.893644349@linutronix.de |
|
|
Thomas Gleixner
|
92853a7774 |
x86/cpu: Move __max_die_per_package to common.c
In preparation of a complete replacement for the topology leaf 0xb/0x1f evaluation, move __max_die_per_package into the common code. Will be removed once everything is converted over. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Zhang Rui <rui.zhang@intel.com> Tested-by: Wang Wendy <wendy.wang@intel.com> Tested-by: K Prateek Nayak <kprateek.nayak@amd.com> Link: https://lore.kernel.org/r/20240212153624.768188958@linutronix.de |
|
|
Thomas Gleixner
|
bda74aae20 |
x86/cpu: Add legacy topology parser
The legacy topology detection via CPUID leaf 4, which provides the number of cores in the package and CPUID leaf 1 which provides the number of logical CPUs in case that FEATURE_HT is enabled and the CMP_LEGACY feature is not set, is shared for Intel, Centaur and Zhaoxin CPUs. Lift the code from common.c without the early detection hack and provide it as common fallback mechanism. Will be utilized in later changes. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Zhang Rui <rui.zhang@intel.com> Tested-by: Wang Wendy <wendy.wang@intel.com> Tested-by: K Prateek Nayak <kprateek.nayak@amd.com> Link: https://lore.kernel.org/r/20240212153624.644448852@linutronix.de |
|
|
Thomas Gleixner
|
ebdb203610 |
x86/cpu: Provide cpu_init/parse_topology()
Topology evaluation is a complete disaster and impenetrable mess. It's
scattered all over the place with some vendor implementations doing early
evaluation and some not. The most horrific part is the permanent
overwriting of smt_max_siblings and __max_die_per_package, instead of
establishing them once on the boot CPU and validating the result on the
APs.
The goals are:
- One topology evaluation entry point
- Proper sharing of pointlessly duplicated code
- Proper structuring of the evaluation logic and preferences.
- Evaluating important system wide information only once on the boot CPU
- Making the 0xb/0x1f leaf parsing less convoluted and actually fixing
the short comings of leaf 0x1f evaluation.
Start to consolidate the topology evaluation code by providing the entry
points for the early boot CPU evaluation and for the final parsing on the
boot CPU and the APs.
Move the trivial pieces into that new code:
- The initialization of cpuinfo_x86::topo
- The evaluation of CPUID leaf 1, which presets topo::initial_apicid
- topo_apicid is set to topo::initial_apicid when invoked from early
boot. When invoked for the final evaluation on the boot CPU it reads
the actual APIC ID, which makes apic_get_initial_apicid() obsolete
once everything is converted over.
Provide a temporary helper function topo_converted() which shields off the
not yet converted CPU vendors from invoking code which would break them.
This shielding covers all vendor CPUs which support SMP, but not the
historical pure UP ones as they only need the topology info init and
eventually the initial APIC initialization.
Provide two new members in cpuinfo_x86::topo to store the maximum number of
SMT siblings and the number of dies per package and add them to the debugfs
readout. These two members will be used to populate this information on the
boot CPU and to validate the APs against it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Wang Wendy <wendy.wang@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240212153624.581436579@linutronix.de
|
|
|
Ingo Molnar
|
03c11eb3b1 |
Linux 6.8-rc4
-----BEGIN PGP SIGNATURE----- iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAmXJK4UeHHRvcnZhbGRz QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGHsYH/jKmzKXDRsBCcw/Q HGUvFtpohWBOpN6efdf0nxilQisuyQrqKB9fnwvfcdE60VpqMJXFMdlFh/fonxPl JMbpk9y5uw48IJZA43NwTxUrjZ4wyWzv4ZF6YWa+5WdTAJpPLEPhhnLxcHOKklMr 5Cm/7B/M7eB2BXBfc45b1pkKN22q9OXvjaKxZ+5wYmiMxS+GC8l8jiJ/WlHX78PR eLgsa1v732f2D7YF75wVhaoYepR+QzA9wTKqhjMNCEaVc2PQhA2JRsBXEt84qEIa FZigmf7LLc4ed9YA2XjRBZhAehe3cZVJZ1lasW37IATS921La2WfKuiysICJOtyT bGjK8tk= =Pt7W -----END PGP SIGNATURE----- Merge tag 'v6.8-rc4' into x86/percpu, to resolve conflicts and refresh the branch Conflicts: arch/x86/include/asm/percpu.h arch/x86/include/asm/text-patching.h Signed-off-by: Ingo Molnar <mingo@kernel.org> |
|
H. Peter Anvin (Intel)
|
208d8c79fd |
x86/fred: Invoke FRED initialization code to enable FRED
Let cpu_init_exception_handling() call cpu_init_fred_exceptions() to initialize FRED. However if FRED is unavailable or disabled, it falls back to set up TSS IST and initialize IDT. Co-developed-by: Xin Li <xin3.li@intel.com> Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com> Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Shan Kang <shan.kang@intel.com> Link: https://lore.kernel.org/r/20231205105030.8698-36-xin3.li@intel.com |
|
Xin Li
|
530dce278a |
x86/syscall: Split IDT syscall setup code into idt_syscall_init()
Because FRED uses the ring 3 FRED entrypoint for SYSCALL and SYSENTER and ERETU is the only legit instruction to return to ring 3, there is NO need to setup SYSCALL and SYSENTER MSRs for FRED, except the IA32_STAR MSR. Split IDT syscall setup code into idt_syscall_init() to make it easy to skip syscall setup code when FRED is enabled. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Shan Kang <shan.kang@intel.com> Link: https://lore.kernel.org/r/20231205105030.8698-34-xin3.li@intel.com |
|
|
H. Peter Anvin (Intel)
|
ff45746fbf |
x86/cpu: Add X86_CR4_FRED macro
Add X86_CR4_FRED macro for the FRED bit in %cr4. This bit must not be changed after initialization, so add it to the pinned CR4 bits. Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com> Signed-off-by: Xin Li <xin3.li@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Shan Kang <shan.kang@intel.com> Link: https://lore.kernel.org/r/20231205105030.8698-12-xin3.li@intel.com |
|
Kim Phillips
|
acaa4b5c4c |
x86/speculation: Do not enable Automatic IBRS if SEV-SNP is enabled
Without SEV-SNP, Automatic IBRS protects only the kernel. But when SEV-SNP is enabled, the Automatic IBRS protection umbrella widens to all host-side code, including userspace. This protection comes at a cost: reduced userspace indirect branch performance. To avoid this performance loss, don't use Automatic IBRS on SEV-SNP hosts and all back to retpolines instead. [ mdr: squash in changes from review discussion. ] Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Dave Hansen <dave.hansen@intel.com> Link: https://lore.kernel.org/r/20240126041126.1927228-3-michael.roth@amd.com |
|
|
Linus Torvalds
|
b4442cadca |
- Add support managing TDX host hardware
-----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEV76QKkVc4xCGURexaDWVMHDJkrAFAmWfCRQACgkQaDWVMHDJ krDUqQ//VCvkpf0mAbYDJa1oTXFW8O5cVTusBtPi8k7cFbtjQpjno/9AqKol+sK8 AKg+y5iHHl7QJmDmEcpS+O9OBbmFOpvDzm3QZhk8RkWS5pe0B108dnINYtS0eP9R MkzZwfrI2yC6NX4hvHGdD8WGHjrt+oxY0bojehX87JZsyRU+xqc/g1OO7a5bUPQe 3Ip0kKiCeqFv0y+Q1pFMEd9RdZ8XxqzUHCJT3hfgZ6FajJ2eVy6jNrPOm6LozycB eOtYYNapSgw3k/WhJCOYWHX7kePXibLxBRONLpi6P3U6pMVk4n8wrgl7qPtdW1Qx nR2UHX5P6eFkxNCuU1BzvmPBROe37C51MFVw29eRnigvuX3j/vfCH1+17xQOVKVv 5JyxYA0rJWqoOz6mX7YaNJHlmrxHzeKXudICyOFuu1j5c8CuGjh8NQsOSCq16XfZ hPzfYDUS8I7/kHYQPJlnB+kF9pmbyjTM70h74I8D6ZWvXESHJZt+TYPyWfkBXP/P L9Pwx1onAyoBApGxCWuvgGTLonzNredgYG4ABbqhUqxqncJS9M7Y/yJa+f+3SOkR T6LxoByuDVld5cIfbOzRwIaRezZDe/NL7rkHm/DWo98OaV3zILsr20Hx1lPZ1Vce ryZ9lCdZGGxm2jmpzr/VymPQz/E+ezahRHE1+F3su8jpCU41txg= =1EJI -----END PGP SIGNATURE----- Merge tag 'x86_tdx_for_6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 TDX updates from Dave Hansen: "This contains the initial support for host-side TDX support so that KVM can run TDX-protected guests. This does not include the actual KVM-side support which will come from the KVM folks. The TDX host interactions with kexec also needs to be ironed out before this is ready for prime time, so this code is currently Kconfig'd off when kexec is on. The majority of the code here is the kernel telling the TDX module which memory to protect and handing some additional memory over to it to use to store TDX module metadata. That sounds pretty simple, but the TDX architecture is rather flexible and it takes quite a bit of back-and-forth to say, "just protect all memory, please." There is also some code tacked on near the end of the series to handle a hardware erratum. The erratum can make software bugs such as a kernel write to TDX-protected memory cause a machine check and masquerade as a real hardware failure. The erratum handling watches out for these and tries to provide nicer user errors" * tag 'x86_tdx_for_6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits) x86/virt/tdx: Make TDX host depend on X86_MCE x86/virt/tdx: Disable TDX host support when kexec is enabled Documentation/x86: Add documentation for TDX host support x86/mce: Differentiate real hardware #MCs from TDX erratum ones x86/cpu: Detect TDX partial write machine check erratum x86/virt/tdx: Handle TDX interaction with sleep and hibernation x86/virt/tdx: Initialize all TDMRs x86/virt/tdx: Configure global KeyID on all packages x86/virt/tdx: Configure TDX module with the TDMRs and global KeyID x86/virt/tdx: Designate reserved areas for all TDMRs x86/virt/tdx: Allocate and set up PAMTs for TDMRs x86/virt/tdx: Fill out TDMRs to cover all TDX memory regions x86/virt/tdx: Add placeholder to construct TDMRs to cover all TDX memory regions x86/virt/tdx: Get module global metadata for module initialization x86/virt/tdx: Use all system memory when initializing TDX module as TDX memory x86/virt/tdx: Add skeleton to enable TDX on demand x86/virt/tdx: Add SEAMCALL error printing for module initialization x86/virt/tdx: Handle SEAMCALL no entropy error in common code x86/virt/tdx: Make INTEL_TDX_HOST depend on X86_X2APIC x86/virt/tdx: Define TDX supported page sizes as macros ... |
|
|
Linus Torvalds
|
106b88d7a9 |
x86/asm changes for v6.8:
- Replace magic numbers in GDT descriptor definitions & handling:
- Introduce symbolic names via macros for descriptor types/fields/flags,
and then use these symbolic names.
- Clean up definitions a bit, such as GDT_ENTRY_INIT()
- Fix/clean up details that became visibly inconsistent after the
symbol-based code was introduced:
- Unify accessed flag handling
- Set the D/B size flag consistently & according to the HW specification
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=Y0pg
-----END PGP SIGNATURE-----
Merge tag 'x86-asm-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar:
"Replace magic numbers in GDT descriptor definitions & handling:
- Introduce symbolic names via macros for descriptor
types/fields/flags, and then use these symbolic names.
- Clean up definitions a bit, such as GDT_ENTRY_INIT()
- Fix/clean up details that became visibly inconsistent after the
symbol-based code was introduced:
- Unify accessed flag handling
- Set the D/B size flag consistently & according to the HW
specification"
* tag 'x86-asm-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/asm: Add DB flag to 32-bit percpu GDT entry
x86/asm: Always set A (accessed) flag in GDT descriptors
x86/asm: Replace magic numbers in GDT descriptors, script-generated change
x86/asm: Replace magic numbers in GDT descriptors, preparations
x86/asm: Provide new infrastructure for GDT descriptors
|
|
Vegard Nossum
|
3b184b71df |
x86/asm: Always set A (accessed) flag in GDT descriptors
We have no known use for having the CPU track whether GDT descriptors have been accessed or not. Simplify the code by adding the flag to the common flags and removing it everywhere else. Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20231219151200.2878271-5-vegard.nossum@oracle.com |
|
|
Vegard Nossum
|
1445f6e15f |
x86/asm: Replace magic numbers in GDT descriptors, script-generated change
Actually replace the numeric values by the new symbolic values.
I used this to find all the existing users of the GDT_ENTRY*() macros:
$ git grep -P 'GDT_ENTRY(_INIT)?\('
Some of the lines will exceed 80 characters, but some of them will be
shorter again in the next couple of patches.
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20231219151200.2878271-4-vegard.nossum@oracle.com
|
|
|
Vegard Nossum
|
41ef75c848 |
x86/asm: Replace magic numbers in GDT descriptors, preparations
We'd like to replace all the magic numbers in various GDT descriptors with new, semantically meaningful, symbolic values. In order to be able to verify that the change doesn't cause any actual changes to the compiled binary code, I've split the change into two patches: - Part 1 (this commit): everything _but_ actually replacing the numbers - Part 2 (the following commit): _only_ replacing the numbers The reason we need this split for verification is that including new headers causes some spurious changes to the object files, mostly line number changes in the debug info but occasionally other subtle codegen changes. Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20231219151200.2878271-3-vegard.nossum@oracle.com |
|
Kai Huang
|
765a0542fd |
x86/virt/tdx: Detect TDX during kernel boot
Intel Trust Domain Extensions (TDX) protects guest VMs from malicious host and certain physical attacks. A CPU-attested software module called 'the TDX module' runs inside a new isolated memory range as a trusted hypervisor to manage and run protected VMs. Pre-TDX Intel hardware has support for a memory encryption architecture called MKTME. The memory encryption hardware underpinning MKTME is also used for Intel TDX. TDX ends up "stealing" some of the physical address space from the MKTME architecture for crypto-protection to VMs. The BIOS is responsible for partitioning the "KeyID" space between legacy MKTME and TDX. The KeyIDs reserved for TDX are called 'TDX private KeyIDs' or 'TDX KeyIDs' for short. During machine boot, TDX microcode verifies that the BIOS programmed TDX private KeyIDs consistently and correctly programmed across all CPU packages. The MSRs are locked in this state after verification. This is why MSR_IA32_MKTME_KEYID_PARTITIONING gets used for TDX enumeration: it indicates not just that the hardware supports TDX, but that all the boot-time security checks passed. The TDX module is expected to be loaded by the BIOS when it enables TDX, but the kernel needs to properly initialize it before it can be used to create and run any TDX guests. The TDX module will be initialized by the KVM subsystem when KVM wants to use TDX. Detect platform TDX support by detecting TDX private KeyIDs. The TDX module itself requires one TDX KeyID as the 'TDX global KeyID' to protect its metadata. Each TDX guest also needs a TDX KeyID for its own protection. Just use the first TDX KeyID as the global KeyID and leave the rest for TDX guests. If no TDX KeyID is left for TDX guests, disable TDX as initializing the TDX module alone is useless. [ dhansen: add X86_FEATURE, replace helper function ] Signed-off-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Link: https://lore.kernel.org/all/20231208170740.53979-1-dave.hansen%40intel.com |
|
|
Borislav Petkov (AMD)
|
04c3024560 |
x86/barrier: Do not serialize MSR accesses on AMD
AMD does not have the requirement for a synchronization barrier when
acccessing a certain group of MSRs. Do not incur that unnecessary
penalty there.
There will be a CPUID bit which explicitly states that a MFENCE is not
needed. Once that bit is added to the APM, this will be extended with
it.
While at it, move to processor.h to avoid include hell. Untangling that
file properly is a matter for another day.
Some notes on the performance aspect of why this is relevant, courtesy
of Kishon VijayAbraham <Kishon.VijayAbraham@amd.com>:
On a AMD Zen4 system with 96 cores, a modified ipi-bench[1] on a VM
shows x2AVIC IPI rate is 3% to 4% lower than AVIC IPI rate. The
ipi-bench is modified so that the IPIs are sent between two vCPUs in the
same CCX. This also requires to pin the vCPU to a physical core to
prevent any latencies. This simulates the use case of pinning vCPUs to
the thread of a single CCX to avoid interrupt IPI latency.
In order to avoid run-to-run variance (for both x2AVIC and AVIC), the
below configurations are done:
1) Disable Power States in BIOS (to prevent the system from going to
lower power state)
2) Run the system at fixed frequency 2500MHz (to prevent the system
from increasing the frequency when the load is more)
With the above configuration:
*) Performance measured using ipi-bench for AVIC:
Average Latency: 1124.98ns [Time to send IPI from one vCPU to another vCPU]
Cumulative throughput: 42.6759M/s [Total number of IPIs sent in a second from
48 vCPUs simultaneously]
*) Performance measured using ipi-bench for x2AVIC:
Average Latency: 1172.42ns [Time to send IPI from one vCPU to another vCPU]
Cumulative throughput: 40.9432M/s [Total number of IPIs sent in a second from
48 vCPUs simultaneously]
From above, x2AVIC latency is ~4% more than AVIC. However, the expectation is
x2AVIC performance to be better or equivalent to AVIC. Upon analyzing
the perf captures, it is observed significant time is spent in
weak_wrmsr_fence() invoked by x2apic_send_IPI().
With the fix to skip weak_wrmsr_fence()
*) Performance measured using ipi-bench for x2AVIC:
Average Latency: 1117.44ns [Time to send IPI from one vCPU to another vCPU]
Cumulative throughput: 42.9608M/s [Total number of IPIs sent in a second from
48 vCPUs simultaneously]
Comparing the performance of x2AVIC with and without the fix, it can be seen
the performance improves by ~4%.
Performance captured using an unmodified ipi-bench using the 'mesh-ipi' option
with and without weak_wrmsr_fence() on a Zen4 system also showed significant
performance improvement without weak_wrmsr_fence(). The 'mesh-ipi' option ignores
CCX or CCD and just picks random vCPU.
Average throughput (10 iterations) with weak_wrmsr_fence(),
Cumulative throughput: 4933374 IPI/s
Average throughput (10 iterations) without weak_wrmsr_fence(),
Cumulative throughput:
|
|
|
Linus Torvalds
|
0a23fb262d |
Major microcode loader restructuring, cleanup and improvements by Thomas
Gleixner:
- Restructure the code needed for it and add a temporary initrd mapping
on 32-bit so that the loader can access the microcode blobs. This in
itself is a preparation for the next major improvement:
- Do not load microcode on 32-bit before paging has been enabled.
Handling this has caused an endless stream of headaches, issues, ugly
code and unnecessary hacks in the past. And there really wasn't any
sensible reason to do that in the first place. So switch the 32-bit
loading to happen after paging has been enabled and turn the loader
code "real purrty" again
- Drop mixed microcode steppings loading on Intel - there, a single patch
loaded on the whole system is sufficient
- Rework late loading to track which CPUs have updated microcode
successfully and which haven't, act accordingly
- Move late microcode loading on Intel in NMI context in order to
guarantee concurrent loading on all threads
- Make the late loading CPU-hotplug-safe and have the offlined threads
be woken up for the purpose of the update
- Add support for a minimum revision which determines whether late
microcode loading is safe on a machine and the microcode does not
change software visible features which the machine cannot use anyway
since feature detection has happened already. Roughly, the minimum
revision is the smallest revision number which must be loaded
currently on the system so that late updates can be allowed
- Other nice leanups, fixess, etc all over the place
-----BEGIN PGP SIGNATURE-----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=JOZu
-----END PGP SIGNATURE-----
Merge tag 'x86_microcode_for_v6.7_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 microcode loading updates from Borislac Petkov:
"Major microcode loader restructuring, cleanup and improvements by
Thomas Gleixner:
- Restructure the code needed for it and add a temporary initrd
mapping on 32-bit so that the loader can access the microcode
blobs. This in itself is a preparation for the next major
improvement:
- Do not load microcode on 32-bit before paging has been enabled.
Handling this has caused an endless stream of headaches, issues,
ugly code and unnecessary hacks in the past. And there really
wasn't any sensible reason to do that in the first place. So switch
the 32-bit loading to happen after paging has been enabled and turn
the loader code "real purrty" again
- Drop mixed microcode steppings loading on Intel - there, a single
patch loaded on the whole system is sufficient
- Rework late loading to track which CPUs have updated microcode
successfully and which haven't, act accordingly
- Move late microcode loading on Intel in NMI context in order to
guarantee concurrent loading on all threads
- Make the late loading CPU-hotplug-safe and have the offlined
threads be woken up for the purpose of the update
- Add support for a minimum revision which determines whether late
microcode loading is safe on a machine and the microcode does not
change software visible features which the machine cannot use
anyway since feature detection has happened already. Roughly, the
minimum revision is the smallest revision number which must be
loaded currently on the system so that late updates can be allowed
- Other nice leanups, fixess, etc all over the place"
* tag 'x86_microcode_for_v6.7_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
x86/microcode/intel: Add a minimum required revision for late loading
x86/microcode: Prepare for minimal revision check
x86/microcode: Handle "offline" CPUs correctly
x86/apic: Provide apic_force_nmi_on_cpu()
x86/microcode: Protect against instrumentation
x86/microcode: Rendezvous and load in NMI
x86/microcode: Replace the all-in-one rendevous handler
x86/microcode: Provide new control functions
x86/microcode: Add per CPU control field
x86/microcode: Add per CPU result state
x86/microcode: Sanitize __wait_for_cpus()
x86/microcode: Clarify the late load logic
x86/microcode: Handle "nosmt" correctly
x86/microcode: Clean up mc_cpu_down_prep()
x86/microcode: Get rid of the schedule work indirection
x86/microcode: Mop up early loading leftovers
x86/microcode/amd: Use cached microcode for AP load
x86/microcode/amd: Cache builtin/initrd microcode early
x86/microcode/amd: Cache builtin microcode too
x86/microcode/amd: Use correct per CPU ucode_cpu_info
...
|
|
|
Linus Torvalds
|
eb55307e67 |
X86 core code updates:
- Limit the hardcoded topology quirk for Hygon CPUs to those which have a
model ID less than 4. The newer models have the topology CPUID leaf 0xB
correctly implemented and are not affected.
- Make SMT control more robust against enumeration failures
SMT control was added to allow controlling SMT at boottime or
runtime. The primary purpose was to provide a simple mechanism to
disable SMT in the light of speculation attack vectors.
It turned out that the code is sensible to enumeration failures and
worked only by chance for XEN/PV. XEN/PV has no real APIC enumeration
which means the primary thread mask is not set up correctly. By chance
a XEN/PV boot ends up with smp_num_siblings == 2, which makes the
hotplug control stay at its default value "enabled". So the mask is
never evaluated.
The ongoing rework of the topology evaluation caused XEN/PV to end up
with smp_num_siblings == 1, which sets the SMT control to "not
supported" and the empty primary thread mask causes the hotplug core to
deny the bringup of the APS.
Make the decision logic more robust and take 'not supported' and 'not
implemented' into account for the decision whether a CPU should be
booted or not.
- Fake primary thread mask for XEN/PV
Pretend that all XEN/PV vCPUs are primary threads, which makes the
usage of the primary thread mask valid on XEN/PV. That is consistent
with because all of the topology information on XEN/PV is fake or even
non-existent.
- Encapsulate topology information in cpuinfo_x86
Move the randomly scattered topology data into a separate data
structure for readability and as a preparatory step for the topology
evaluation overhaul.
- Consolidate APIC ID data type to u32
It's fixed width hardware data and not randomly u16, int, unsigned long
or whatever developers decided to use.
- Cure the abuse of cpuinfo for persisting logical IDs.
Per CPU cpuinfo is used to persist the logical package and die
IDs. That's really not the right place simply because cpuinfo is
subject to be reinitialized when a CPU goes through an offline/online
cycle.
Use separate per CPU data for the persisting to enable the further
topology management rework. It will be removed once the new topology
management is in place.
- Provide a debug interface for inspecting topology information
Useful in general and extremly helpful for validating the topology
management rework in terms of correctness or "bug" compatibility.
-----BEGIN PGP SIGNATURE-----
iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmU+yX0THHRnbHhAbGlu
dXRyb25peC5kZQAKCRCmGPVMDXSYoROUD/4vlvKEcpm9rbI5DzLcaq4DFHKbyEZF
cQtzuOSM/9vTc9DHnuoNNLl9TWSYxiVYnejf3E21evfsqspYlzbTH8bId9XBCUid
6B68AJW842M2erNuwj0b0HwF1z++zpDmBDyhGOty/KQhoM8pYOHMvntAmbzJbuso
Dgx6BLVFcboTy6RwlfRa0EE8f9W5V+JbmG/VBDpdyCInal7VrudoVFZmWQnPIft7
zwOJpAoehkp8OKq7geKDf79yWxu9a1sNPd62HtaVEvfHwehHqE6OaMLss1us+0vT
SJ/D6gmRQBOwcXaZL0wL1dG7Km9Et4AisOvzhXGvTa5b2D5oljVoqJ7V7FTf5g3u
y3aqWbeUJzERUbeJt1HoGVAKyA4GtZOvg+TNIysf6F1Z4khl9alfa9jiqjj4g1au
zgItq/ZMBEBmJ7X4FxQUEUVBG2CDsEidyNBDRcimWQUDfBakV/iCs0suD8uu8ZOD
K5jMx8Hi2+xFx7r1YqsfsyMBYOf/zUZw65RbNe+kI992JbJ9nhcODbnbo5MlAsyv
vcqlK5FwXgZ4YAC8dZHU/tyTiqAW7oaOSkqKwTP5gcyNEqsjQHV//q6v+uqtjfYn
1C4oUsRHT2vJiV9ktNJTA4GQHIYF4geGgpG8Ih2SjXsSzdGtUd3DtX1iq0YiLEOk
eHhYsnniqsYB5g==
=xrz8
-----END PGP SIGNATURE-----
Merge tag 'x86-core-2023-10-29-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 core updates from Thomas Gleixner:
- Limit the hardcoded topology quirk for Hygon CPUs to those which have
a model ID less than 4.
The newer models have the topology CPUID leaf 0xB correctly
implemented and are not affected.
- Make SMT control more robust against enumeration failures
SMT control was added to allow controlling SMT at boottime or
runtime. The primary purpose was to provide a simple mechanism to
disable SMT in the light of speculation attack vectors.
It turned out that the code is sensible to enumeration failures and
worked only by chance for XEN/PV. XEN/PV has no real APIC enumeration
which means the primary thread mask is not set up correctly. By
chance a XEN/PV boot ends up with smp_num_siblings == 2, which makes
the hotplug control stay at its default value "enabled". So the mask
is never evaluated.
The ongoing rework of the topology evaluation caused XEN/PV to end up
with smp_num_siblings == 1, which sets the SMT control to "not
supported" and the empty primary thread mask causes the hotplug core
to deny the bringup of the APS.
Make the decision logic more robust and take 'not supported' and 'not
implemented' into account for the decision whether a CPU should be
booted or not.
- Fake primary thread mask for XEN/PV
Pretend that all XEN/PV vCPUs are primary threads, which makes the
usage of the primary thread mask valid on XEN/PV. That is consistent
with because all of the topology information on XEN/PV is fake or
even non-existent.
- Encapsulate topology information in cpuinfo_x86
Move the randomly scattered topology data into a separate data
structure for readability and as a preparatory step for the topology
evaluation overhaul.
- Consolidate APIC ID data type to u32
It's fixed width hardware data and not randomly u16, int, unsigned
long or whatever developers decided to use.
- Cure the abuse of cpuinfo for persisting logical IDs.
Per CPU cpuinfo is used to persist the logical package and die IDs.
That's really not the right place simply because cpuinfo is subject
to be reinitialized when a CPU goes through an offline/online cycle.
Use separate per CPU data for the persisting to enable the further
topology management rework. It will be removed once the new topology
management is in place.
- Provide a debug interface for inspecting topology information
Useful in general and extremly helpful for validating the topology
management rework in terms of correctness or "bug" compatibility.
* tag 'x86-core-2023-10-29-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
x86/apic, x86/hyperv: Use u32 in hv_snp_boot_ap() too
x86/cpu: Provide debug interface
x86/cpu/topology: Cure the abuse of cpuinfo for persisting logical ids
x86/apic: Use u32 for wakeup_secondary_cpu[_64]()
x86/apic: Use u32 for [gs]et_apic_id()
x86/apic: Use u32 for phys_pkg_id()
x86/apic: Use u32 for cpu_present_to_apicid()
x86/apic: Use u32 for check_apicid_used()
x86/apic: Use u32 for APIC IDs in global data
x86/apic: Use BAD_APICID consistently
x86/cpu: Move cpu_l[l2]c_id into topology info
x86/cpu: Move logical package and die IDs into topology info
x86/cpu: Remove pointless evaluation of x86_coreid_bits
x86/cpu: Move cu_id into topology info
x86/cpu: Move cpu_core_id into topology info
hwmon: (fam15h_power) Use topology_core_id()
scsi: lpfc: Use topology_core_id()
x86/cpu: Move cpu_die_id into topology info
x86/cpu: Move phys_proc_id into topology info
x86/cpu: Encapsulate topology information in cpuinfo_x86
...
|
|
|
Linus Torvalds
|
f0d25b5d0f |
x86 MM handling code changes for v6.7:
- Add new NX-stack self-test - Improve NUMA partial-CFMWS handling - Fix #VC handler bugs resulting in SEV-SNP boot failures - Drop the 4MB memory size restriction on minimal NUMA nodes - Reorganize headers a bit, in preparation to header dependency reduction efforts - Misc cleanups & fixes Signed-off-by: Ingo Molnar <mingo@kernel.org> -----BEGIN PGP SIGNATURE----- iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmU9Ek4RHG1pbmdvQGtl cm5lbC5vcmcACgkQEnMQ0APhK1gIJQ/+Mg6mzMaThyNXqhJszeZJBmDaBv2sqjAB 5tcferg1nJBdNBzX8bJ95UFt9fIqeYAcgH00qlQCYSmyzbC1TQTk9U2Pre1zbOw4 042ONK8sygKSje1zdYleHoBeqwnxD2VNM0NwBElhGjumwHRng/tbLiI9wx6qiz+C VsFXavkBszHGA1pjy9wZLGixYIH5jCygMpH134Wp+CIhpS+C4nftcGdIL1D5Oil1 6Tm2XeI6uyfiQhm9IOwDjfoYeC7gUjx1rp8rHseGUMJxyO/BX9q5j1ixbsVriqfW 97ucYuRL9mza7ic516C9v7OlAA3AGH2xWV+SYOGK88i9Co4kYzP4WnamxXqOsD8+ popxG55oa6QelhaouTBZvgERpZ4fWupSDs/UccsDaE9leMCerNEbGHEzt/Mm/2sw xopjMQ0y5Kn6/fS0dLv8U+XHu4ANkvXJkFd6Ny0h/WfgGefuQOOTG9ruYgfeqqB8 dViQ4R7CO8ySjD45KawAZl/EqL86x1M/CI1nlt0YY4vNwUuOJbebL7Jn8w3Fjxm5 FVfUlDmcPdhZfL9Vnrsi6MIou1cU1yJPw4D6sXJ4sg4s7A4ebBcRRrjayVQ4msjv Q7cvBOMnWEHhOV11pvP50FmQuj74XW3bUqiuWrnK1SypvnhHavF6kc1XYpBLs1xZ y8nueJW2qPw= =tT5F -----END PGP SIGNATURE----- Merge tag 'x86-mm-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm handling updates from Ingo Molnar: - Add new NX-stack self-test - Improve NUMA partial-CFMWS handling - Fix #VC handler bugs resulting in SEV-SNP boot failures - Drop the 4MB memory size restriction on minimal NUMA nodes - Reorganize headers a bit, in preparation to header dependency reduction efforts - Misc cleanups & fixes * tag 'x86-mm-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Drop the 4 MB restriction on minimal NUMA node memory size selftests/x86/lam: Zero out buffer for readlink() x86/sev: Drop unneeded #include x86/sev: Move sev_setup_arch() to mem_encrypt.c x86/tdx: Replace deprecated strncpy() with strtomem_pad() selftests/x86/mm: Add new test that userspace stack is in fact NX x86/sev: Make boot_ghcb_page[] static x86/boot: Move x86_cache_alignment initialization to correct spot x86/sev-es: Set x86_virt_bits to the correct value straight away, instead of a two-phase approach x86/sev-es: Allow copy_from_kernel_nofault() in earlier boot x86_64: Show CR4.PSE on auxiliaries like on BSP x86/iommu/docs: Update AMD IOMMU specification document URL x86/sev/docs: Update document URL in amd-memory-encryption.rst x86/mm: Move arch_memory_failure() and arch_is_platform_page() definitions from <asm/processor.h> to <asm/pgtable.h> ACPI/NUMA: Apply SRAT proximity domain to entire CFMWS window x86/numa: Introduce numa_fill_memblks() |
|
Uros Bizjak
|
ed2f752e0e |
x86/percpu: Introduce const-qualified const_pcpu_hot to micro-optimize code generation
Some variables in pcpu_hot, currently current_task and top_of_stack
are actually per-thread variables implemented as per-CPU variables
and thus stable for the duration of the respective task. There is
already an attempt to eliminate redundant reads from these variables
using this_cpu_read_stable() asm macro, which hides the dependency
on the read memory address. However, the compiler has limited ability
to eliminate asm common subexpressions, so this approach results in a
limited success.
The solution is to allow more aggressive elimination by aliasing
pcpu_hot into a const-qualified const_pcpu_hot, and to read stable
per-CPU variables from this constant copy.
The current per-CPU infrastructure does not support reads from
const-qualified variables. However, when the compiler supports segment
qualifiers, it is possible to declare the const-aliased variable in
the relevant named address space. The compiler considers access to the
variable, declared in this way, as a read from a constant location,
and will optimize reads from the variable accordingly.
By implementing constant-qualified const_pcpu_hot, the compiler can
eliminate redundant reads from the constant variables, reducing the
number of loads from current_task from 3766 to 3217 on a test build,
a -14.6% reduction.
The reduction of loads translates to the following code savings:
text data bss dec hex filename
25,477,353 4389456 808452 30675261 1d4113d vmlinux-old.o
25,476,074 4389440 808452 30673966 1d40c2e vmlinux-new.o
representing a code size reduction of -1279 bytes.
[ mingo: Updated the changelog, EXPORT(const_pcpu_hot). ]
Co-developed-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20231020162004.135244-1-ubizjak@gmail.com
|
|
|
Thomas Gleixner
|
0b62f6cb07 |
x86/microcode/32: Move early loading after paging enable
32-bit loads microcode before paging is enabled. The commit which
introduced that has zero justification in the changelog. The cover
letter has slightly more content, but it does not give any technical
justification either:
"The problem in current microcode loading method is that we load a
microcode way, way too late; ideally we should load it before turning
paging on. This may only be practical on 32 bits since we can't get
to 64-bit mode without paging on, but we should still do it as early
as at all possible."
Handwaving word salad with zero technical content.
Someone claimed in an offlist conversation that this is required for
curing the ATOM erratum AAE44/AAF40/AAG38/AAH41. That erratum requires
an microcode update in order to make the usage of PSE safe. But during
early boot, PSE is completely irrelevant and it is evaluated way later.
Neither is it relevant for the AP on single core HT enabled CPUs as the
microcode loading on the AP is not doing anything.
On dual core CPUs there is a theoretical problem if a split of an
executable large page between enabling paging including PSE and loading
the microcode happens. But that's only theoretical, it's practically
irrelevant because the affected dual core CPUs are 64bit enabled and
therefore have paging and PSE enabled before loading the microcode on
the second core. So why would it work on 64-bit but not on 32-bit?
The erratum:
"AAG38 Code Fetch May Occur to Incorrect Address After a Large Page is
Split Into 4-Kbyte Pages
Problem: If software clears the PS (page size) bit in a present PDE
(page directory entry), that will cause linear addresses mapped through
this PDE to use 4-KByte pages instead of using a large page after old
TLB entries are invalidated. Due to this erratum, if a code fetch uses
this PDE before the TLB entry for the large page is invalidated then it
may fetch from a different physical address than specified by either the
old large page translation or the new 4-KByte page translation. This
erratum may also cause speculative code fetches from incorrect addresses."
The practical relevance for this is exactly zero because there is no
splitting of large text pages during early boot-time, i.e. between paging
enable and microcode loading, and neither during CPU hotplug.
IOW, this load microcode before paging enable is yet another voodoo
programming solution in search of a problem. What's worse is that it causes
at least two serious problems:
1) When stackprotector is enabled, the microcode loader code has the
stackprotector mechanics enabled. The read from the per CPU variable
__stack_chk_guard is always accessing the virtual address either
directly on UP or via %fs on SMP. In physical address mode this
results in an access to memory above 3GB. So this works by chance as
the hardware returns the same value when there is no RAM at this
physical address. When there is RAM populated above 3G then the read
is by chance the same as nothing changes that memory during the very
early boot stage. That's not necessarily true during runtime CPU
hotplug.
2) When function tracing is enabled, the relevant microcode loader
functions and the functions invoked from there will call into the
tracing code and evaluate global and per CPU variables in physical
address mode. What could potentially go wrong?
Cure this and move the microcode loading after the early paging enable, use
the new temporary initrd mapping and remove the gunk in the microcode
loader which is required to handle physical address mode.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20231017211722.348298216@linutronix.de
|
|
|
Thomas Gleixner
|
8aa2a4178d |
x86/apic: Use u32 for cpu_present_to_apicid()
APIC IDs are used with random data types u16, u32, int, unsigned int, unsigned long. Make it all consistently use u32 because that reflects the hardware register width and fixup a few related usage sites for consistency sake. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Zhang Rui <rui.zhang@intel.com> Reviewed-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230814085113.054064391@linutronix.de |
|
|
Thomas Gleixner
|
6e29032340 |
x86/cpu: Move cpu_l[l2]c_id into topology info
The topology IDs which identify the LLC and L2 domains clearly belong to the per CPU topology information. Move them into cpuinfo_x86::cpuinfo_topo and get rid of the extra per CPU data and the related exports. This also paves the way to do proper topology evaluation during early boot because it removes the only per CPU dependency for that. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Zhang Rui <rui.zhang@intel.com> Reviewed-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230814085112.803864641@linutronix.de |
|
|
Thomas Gleixner
|
22dc963162 |
x86/cpu: Move logical package and die IDs into topology info
Yet another topology related data pair. Rename logical_proc_id to logical_pkg_id so it fits the common naming conventions. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230814085112.745139505@linutronix.de |
|
|
Thomas Gleixner
|
e3c0c5d52a |
x86/cpu: Move cu_id into topology info
No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230814085112.628405546@linutronix.de |
|
|
Thomas Gleixner
|
e95256335d |
x86/cpu: Move cpu_core_id into topology info
Rename it to core_id and stick it to the other ID fields. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230814085112.566519388@linutronix.de |
|
|
Thomas Gleixner
|
8a169ed40f |
x86/cpu: Move cpu_die_id into topology info
Move the next member. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230814085112.388185134@linutronix.de |
|
|
Thomas Gleixner
|
02fb601d27 |
x86/cpu: Move phys_proc_id into topology info
Rename it to pkg_id which is the terminology used in the kernel. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230814085112.329006989@linutronix.de |
|
|
Thomas Gleixner
|
b9655e702d |
x86/cpu: Encapsulate topology information in cpuinfo_x86
The topology related information is randomly scattered across cpuinfo_x86. Create a new structure cpuinfo_topo and move in a first step initial_apicid and apicid into it. Aside of being better readable this is in preparation for replacing the horribly fragile CPU topology evaluation code further down the road. Consolidate APIC ID fields to u32 as that represents the hardware type. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20230814085112.269787744@linutronix.de |
|
|
Ingo Molnar
|
3fc18b06b8 |
Linux 6.6-rc4
-----BEGIN PGP SIGNATURE----- iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAmUZ4WEeHHRvcnZhbGRz QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGnIYH/07zef2U1nlqI+ro HRL2GlWGIs9yE70Oax+A3eYUYsjJIPu0yiDhFHUgOV3VyAALo44ZX/WNwKCGsI3e zhuOeItyyVcLGZXVC/jxSu0uveyfEiEYIWRYGyQ6Sna8Ksdk/qwhNgQNotdWdQG5 7xt8z32couglu0uOkxcGqjTxmbjO6WSM5qi7Ts+xLsgrcS5cRuNhAg/vezp9bfeL 1IUieCih4RJFgar/6LPOiB8uoVXEBonVbtlTRRqYdnqcsSIC+ACR9ZFk/+X88b5z S+Ta5VTcOAPu+2M/lSGe+PlUECvoBNK0SIYnaVCP2paPmDxfDXOFvSy/qJE87/7L 9BeonFw= =8FTr -----END PGP SIGNATURE----- Merge tag 'v6.6-rc4' into x86/entry, to pick up fixes Signed-off-by: Ingo Molnar <mingo@kernel.org> |
|
Dave Hansen
|
3e32552652 |
x86/boot: Move x86_cache_alignment initialization to correct spot
c->x86_cache_alignment is initialized from c->x86_clflush_size. However, commit |
|
Adam Dunlap
|
fbf6449f84 |
x86/sev-es: Set x86_virt_bits to the correct value straight away, instead of a two-phase approach
Instead of setting x86_virt_bits to a possibly-correct value and then correcting it later, do all the necessary checks before setting it. At this point, the #VC handler references boot_cpu_data.x86_virt_bits, and in the previous version, it would be triggered by the CPUIDs between the point at which it is set to 48 and when it is set to the correct value. Suggested-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Adam Dunlap <acdunlap@google.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Jacob Xu <jacobhxu@google.com> Link: https://lore.kernel.org/r/20230912002703.3924521-3-acdunlap@google.com |
|
Pu Wen
|
a5ef7d68ce |
x86/srso: Add SRSO mitigation for Hygon processors
Add mitigation for the speculative return stack overflow vulnerability which exists on Hygon processors too. Signed-off-by: Pu Wen <puwen@hygon.cn> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/tencent_4A14812842F104E93AA722EC939483CEFF05@qq.com |
|
Nikolay Borisov
|
61382281e9 |
x86/entry: Make IA32 syscalls' availability depend on ia32_enabled()
Another major aspect of supporting running of 32bit processes is the ability to access 32bit syscalls. Such syscalls can be invoked by using the legacy int 0x80 handler and sysenter/syscall instructions. If IA32 emulation is disabled ensure that each of those 3 distinct mechanisms are also disabled. For int 0x80 a #GP exception would be generated since the respective descriptor is not going to be loaded at all. Invoking sysenter will also result in a #GP since IA32_SYSENTER_CS contains an invalid segment. Finally, syscall instruction cannot really be disabled so it's configured to execute a minimal handler. Signed-off-by: Nikolay Borisov <nik.borisov@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230623111409.3047467-6-nik.borisov@suse.com |
|
|
Nikolay Borisov
|
f71e1d2ff8 |
x86/entry: Rename ignore_sysret()
The SYSCALL instruction cannot really be disabled in compatibility mode. The best that can be done is to configure the CSTAR msr to point to a minimal handler. Currently this handler has a rather misleading name - ignore_sysret() as it's not really doing anything with sysret. Give it a more descriptive name. Signed-off-by: Nikolay Borisov <nik.borisov@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230623111409.3047467-3-nik.borisov@suse.com |
|
|
Linus Torvalds
|
2fcbb03847 |
* Mark all Skylake CPUs as vulnerable to GDS
* Fix PKRU covert channel * Fix -Wmissing-variable-declarations warning for ia32_xyz_class * Fix kernel-doc annotation warning -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEV76QKkVc4xCGURexaDWVMHDJkrAFAmTyK2sACgkQaDWVMHDJ krCPyA//WbT65hhGZt5UHayoW3Cv8NmS4kRf6FTVMmt1yIvbOtVmWVZeOGMypprC jYBPOdTf1SdoUxeD1cTTd/rtbYknczaBLC5VGilGb2/663yQl9ThT3ePc6OgUpPW 28ItLslfHGchHbrOgCgUK8Aiv8xRdfNUJoByMTOoce6eGUQsgYaNOq74z1YaLsZ4 afbitcd/vWO9eJfW5DNl26rIP+ksOgA/Iue8uRiEczoPltnbUxGGLCtuuR9B2Xxi FqfttvcnUy9yFJBnELx4721VtTcmK4Dq5O/ZoJnmVQqRPY9aXpkbwZnH9co8r/uh GueQj30l6VhEO6XnwPvjsOghXI2vOMrxlL3zGMw5y6pjfUWa4W6f33EV6mByYfml dfPTXIz9K1QxznHtk6xVhn1X8CFw7L1L7CC/2CPQPETiuqyjWrHqvFBXcsWpKq4N 1GjnpoveNZmWcE7UY9qEHAXGh7ndI+EIux/0WfJJHOE/fzCr06GphQdxNwPGdi5O T3JkZf6R4GBvfi6e0F6Qn2B02sDl18remmAMi9bAn/M31g+mvAoHqKLlI9EzAGGz 91PzJdHecdvalU6zsCKqi0ETzq11WG7zCfSXs+jeHBe1jsUITpcZCkpVi2pGA2aq X7qLjJyW+Sx0hdE2IWFhCOfiwGFpXxfegCl1uax3HrZg6rrORbw= =prt2 -----END PGP SIGNATURE----- Merge tag 'x86-urgent-2023-09-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Dave Hansen: "The most important fix here adds a missing CPU model to the recent Gather Data Sampling (GDS) mitigation list to ensure that mitigations are available on that CPU. There are also a pair of warning fixes, and closure of a covert channel that pops up when protection keys are disabled. Summary: - Mark all Skylake CPUs as vulnerable to GDS - Fix PKRU covert channel - Fix -Wmissing-variable-declarations warning for ia32_xyz_class - Fix kernel-doc annotation warning" * tag 'x86-urgent-2023-09-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/fpu/xstate: Fix PKRU covert channel x86/irq/i8259: Fix kernel-doc annotation warning x86/speculation: Mark all Skylake CPUs as vulnerable to GDS x86/audit: Fix -Wmissing-variable-declarations warning for ia32_xyz_class |
|
|
Linus Torvalds
|
df57721f9a |
Add x86 shadow stack support
Convert IBT selftest to asm to fix objtool warning -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEV76QKkVc4xCGURexaDWVMHDJkrAFAmTv1QQACgkQaDWVMHDJ krAUwhAAn6TOwHJK8BSkHeiQhON1nrlP3c5cv0AyZ2NP8RYDrZrSZvhpYBJ6wgKC Cx5CGq5nn9twYsYS3KsktLKDfR3lRdsQ7K9qtyFtYiaeaVKo+7gEKl/K+klwai8/ gninQWHk0zmSCja8Vi77q52WOMkQKapT8+vaON9EVDO8dVEi+CvhAIfPwMafuiwO Rk4X86SzoZu9FP79LcCg9XyGC/XbM2OG9eNUTSCKT40qTTKm5y4gix687NvAlaHR ko5MTsdl0Wfp6Qk0ohT74LnoA2c1g/FluvZIM33ci/2rFpkf9Hw7ip3lUXqn6CPx rKiZ+pVRc0xikVWkraMfIGMJfUd2rhelp8OyoozD7DB7UZw40Q4RW4N5tgq9Fhe9 MQs3p1v9N8xHdRKl365UcOczUxNAmv4u0nV5gY/4FMC6VjldCl2V9fmqYXyzFS4/ Ogg4FSd7c2JyGFKPs+5uXyi+RY2qOX4+nzHOoKD7SY616IYqtgKoz5usxETLwZ6s VtJOmJL0h//z0A7tBliB0zd+SQ5UQQBDC2XouQH2fNX2isJMn0UDmWJGjaHgK6Hh 8jVp6LNqf+CEQS387UxckOyj7fu438hDky1Ggaw4YqowEOhQeqLVO4++x+HITrbp AupXfbJw9h9cMN63Yc0gVxXQ9IMZ+M7UxLtZ3Cd8/PVztNy/clA= =3UUm -----END PGP SIGNATURE----- Merge tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 shadow stack support from Dave Hansen: "This is the long awaited x86 shadow stack support, part of Intel's Control-flow Enforcement Technology (CET). CET consists of two related security features: shadow stacks and indirect branch tracking. This series implements just the shadow stack part of this feature, and just for userspace. The main use case for shadow stack is providing protection against return oriented programming attacks. It works by maintaining a secondary (shadow) stack using a special memory type that has protections against modification. When executing a CALL instruction, the processor pushes the return address to both the normal stack and to the special permission shadow stack. Upon RET, the processor pops the shadow stack copy and compares it to the normal stack copy. For more information, refer to the links below for the earlier versions of this patch set" Link: https://lore.kernel.org/lkml/20220130211838.8382-1-rick.p.edgecombe@intel.com/ Link: https://lore.kernel.org/lkml/20230613001108.3040476-1-rick.p.edgecombe@intel.com/ * tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits) x86/shstk: Change order of __user in type x86/ibt: Convert IBT selftest to asm x86/shstk: Don't retry vm_munmap() on -EINTR x86/kbuild: Fix Documentation/ reference x86/shstk: Move arch detail comment out of core mm x86/shstk: Add ARCH_SHSTK_STATUS x86/shstk: Add ARCH_SHSTK_UNLOCK x86: Add PTRACE interface for shadow stack selftests/x86: Add shadow stack test x86/cpufeatures: Enable CET CR4 bit for shadow stack x86/shstk: Wire in shadow stack interface x86: Expose thread features in /proc/$PID/status x86/shstk: Support WRSS for userspace x86/shstk: Introduce map_shadow_stack syscall x86/shstk: Check that signal frame is shadow stack mem x86/shstk: Check that SSP is aligned on sigreturn x86/shstk: Handle signals for shadow stack x86/shstk: Introduce routines modifying shstk x86/shstk: Handle thread shadow stack x86/shstk: Add user-mode shadow stack support ... |
|
|
Dave Hansen
|
c9f4c45c8e |
x86/speculation: Mark all Skylake CPUs as vulnerable to GDS
The Gather Data Sampling (GDS) vulnerability is common to all Skylake
processors. However, the "client" Skylakes* are now in this list:
https://www.intel.com/content/www/us/en/support/articles/000022396/processors.html
which means they are no longer included for new vulnerabilities here:
https://www.intel.com/content/www/us/en/developer/topic-technology/software-security-guidance/processors-affected-consolidated-product-cpu-model.html
or in other GDS documentation. Thus, they were not included in the
original GDS mitigation patches.
Mark SKYLAKE and SKYLAKE_L as vulnerable to GDS to match all the
other Skylake CPUs (which include Kaby Lake). Also group the CPUs
so that the ones that share the exact same vulnerabilities are next
to each other.
Last, move SRBDS to the end of each line. This makes it clear at a
glance that SKYLAKE_X is unique. Of the five Skylakes, it is the
only "server" CPU and has a different implementation from the
clients of the "special register" hardware, making it immune to SRBDS.
This makes the diff much harder to read, but the resulting table is
worth it.
I very much appreciate the report from Michael Zhivich about this
issue. Despite what level of support a hardware vendor is providing,
the kernel very much needs an accurate and up-to-date list of
vulnerable CPUs. More reports like this are very welcome.
* Client Skylakes are CPUID 406E3/506E3 which is family 6, models
0x4E and 0x5E, aka INTEL_FAM6_SKYLAKE and INTEL_FAM6_SKYLAKE_L.
Reported-by: Michael Zhivich <mzhivich@akamai.com>
Fixes:
|
|
|
Linus Torvalds
|
1687d8aca5 |
* Rework apic callbacks, getting rid of unnecessary ones and
coalescing lots of silly duplicates.
* Use static_calls() instead of indirect calls for apic->foo()
* Tons of cleanups an crap removal along the way
-----BEGIN PGP SIGNATURE-----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=eoKm
-----END PGP SIGNATURE-----
Merge tag 'x86_apic_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 apic updates from Dave Hansen:
"This includes a very thorough rework of the 'struct apic' handlers.
Quite a variety of them popped up over the years, especially in the
32-bit days when odd apics were much more in vogue.
The end result speaks for itself, which is a removal of a ton of code
and static calls to replace indirect calls.
If there's any breakage here, it's likely to be around the 32-bit
museum pieces that get light to no testing these days.
Summary:
- Rework apic callbacks, getting rid of unnecessary ones and
coalescing lots of silly duplicates.
- Use static_calls() instead of indirect calls for apic->foo()
- Tons of cleanups an crap removal along the way"
* tag 'x86_apic_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits)
x86/apic: Turn on static calls
x86/apic: Provide static call infrastructure for APIC callbacks
x86/apic: Wrap IPI calls into helper functions
x86/apic: Mark all hotpath APIC callback wrappers __always_inline
x86/xen/apic: Mark apic __ro_after_init
x86/apic: Convert other overrides to apic_update_callback()
x86/apic: Replace acpi_wake_cpu_handler_update() and apic_set_eoi_cb()
x86/apic: Provide apic_update_callback()
x86/xen/apic: Use standard apic driver mechanism for Xen PV
x86/apic: Provide common init infrastructure
x86/apic: Wrap apic->native_eoi() into a helper
x86/apic: Nuke ack_APIC_irq()
x86/apic: Remove pointless arguments from [native_]eoi_write()
x86/apic/noop: Tidy up the code
x86/apic: Remove pointless NULL initializations
x86/apic: Sanitize APIC ID range validation
x86/apic: Prepare x2APIC for using apic::max_apic_id
x86/apic: Simplify X2APIC ID validation
x86/apic: Add max_apic_id member
x86/apic: Wrap APIC ID validation into an inline
...
|
|
|
Linus Torvalds
|
42a7f6e3ff |
- The first, cleanup part of the microcode loader reorg tglx has been
working on. This part makes the loader core code as it is practically enabled on pretty much every baremetal machine so there's no need to have the Kconfig items. In addition, there are cleanups which prepare for future feature enablement. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmTskfcACgkQEsHwGGHe VUo/hBAAiqVqdc0WASHgVYoO9mD1M2T3oHFz8ceX2pGKf/raZ5UJyit7ybWEZEWG rWXFORRlqOKoKImQm6JhyJsu29Xmi9sTb1WNwEyT8YMdhx8v57hOch3alX7sm2BF 9eOl/77hxt7Pt8keN6gY5w5cydEgBvi8bVe8sfU3hJMwieAMH0q5syRx7fDizcVd qoTicHRjfj5Q8BL5NXtdPEMENYPyV89DVjnUM1HVPpCkoHxmOujewgjs4gY7PsGp qAGB1+IG3aqOWHM9SDIJp5U9tNX2huhqRTcZsNEe8qHTXCv8F8zRzK0J8giM1wed 5aAGC4AfMh/gjryXeMj1nnwoAf5TQw4dK+y+BYXIykdQDV1up+HdDtjrBmJ5Kslf n/8uGLdLLqMQVEE2hT3r1Ft1RqVf3UwWOxzc+KASjKCj0F5djt+F2JDNGoN0sMD9 JDj3Dtvo2e1+aZlcvXWSmMCVMT0By1mbFqirEXT3i1sYwHDx23s+KwY71CdT8gx8 nbEWsaADPRynNbTAI5Z5TFq0Cohs9AUNuotRHYCc0Et5NBlzoN8yAKNW39twUDEt a/Knq1Vnybrp18pE/rDphm+p/K261OuEXfFFVTASSlvgMnVM0UAZZZka7A0DmN+g mvZ2A9hByFk6sELm3QeNrOdex8djeichyY7+EQ13K25wMd/YsX0= =QXDh -----END PGP SIGNATURE----- Merge tag 'x86_microcode_for_v6.6_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode loading updates from Borislav Petkov: "The first, cleanup part of the microcode loader reorg tglx has been working on. The other part wasn't fully ready in time so it will follow on later. This part makes the loader core code as it is practically enabled on pretty much every baremetal machine so there's no need to have the Kconfig items. In addition, there are cleanups which prepare for future feature enablement" * tag 'x86_microcode_for_v6.6_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode: Remove remaining references to CONFIG_MICROCODE_AMD x86/microcode/intel: Remove pointless mutex x86/microcode/intel: Remove debug code x86/microcode: Move core specific defines to local header x86/microcode/intel: Rename get_datasize() since its used externally x86/microcode: Make reload_early_microcode() static x86/microcode: Include vendor headers into microcode.h x86/microcode/intel: Move microcode functions out of cpu/intel.c x86/microcode: Hide the config knob x86/mm: Remove unused microcode.h include x86/microcode: Remove microcode_mutex x86/microcode/AMD: Rip out static buffers |
|
|
Linus Torvalds
|
6f49693a6c |
Updates for the CPU hotplug core:
- Support partial SMT enablement.
So far the sysfs SMT control only allows to toggle between SMT on and
off. That's sufficient for x86 which usually has at max two threads
except for the Xeon PHI platform which has four threads per core.
Though PowerPC has up to 16 threads per core and so far it's only
possible to control the number of enabled threads per core via a
command line option. There is some way to control this at runtime, but
that lacks enforcement and the usability is awkward.
This update expands the sysfs interface and the core infrastructure to
accept numerical values so PowerPC can build SMT runtime control for
partial SMT enablement on top.
The core support has also been provided to the PowerPC maintainers who
added the PowerPC related changes on top.
- Minor cleanups and documentation updates.
-----BEGIN PGP SIGNATURE-----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=JQRJ
-----END PGP SIGNATURE-----
Merge tag 'smp-core-2023-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull CPU hotplug updates from Thomas Gleixner:
"Updates for the CPU hotplug core:
- Support partial SMT enablement.
So far the sysfs SMT control only allows to toggle between SMT on
and off. That's sufficient for x86 which usually has at max two
threads except for the Xeon PHI platform which has four threads per
core
Though PowerPC has up to 16 threads per core and so far it's only
possible to control the number of enabled threads per core via a
command line option. There is some way to control this at runtime,
but that lacks enforcement and the usability is awkward
This update expands the sysfs interface and the core infrastructure
to accept numerical values so PowerPC can build SMT runtime control
for partial SMT enablement on top
The core support has also been provided to the PowerPC maintainers
who added the PowerPC related changes on top
- Minor cleanups and documentation updates"
* tag 'smp-core-2023-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Documentation: core-api/cpuhotplug: Fix state names
cpu/hotplug: Remove unused function declaration cpu_set_state_online()
cpu/SMT: Fix cpu_smt_possible() comment
cpu/SMT: Allow enabling partial SMT states via sysfs
cpu/SMT: Create topology_smt_thread_allowed()
cpu/SMT: Remove topology_smt_supported()
cpu/SMT: Store the current/max number of threads
cpu/SMT: Move smt/control simple exit cases earlier
cpu/SMT: Move SMT prototypes into cpu_smt.h
cpu/hotplug: Remove dependancy against cpu_primary_thread_mask
|
|
Josh Poimboeuf
|
c6cfcbd8ca |
x86/ibt: Convert IBT selftest to asm
The following warning is reported when frame pointers and kernel IBT are enabled: vmlinux.o: warning: objtool: ibt_selftest+0x11: sibling call from callable instruction with modified stack frame The problem is that objtool interprets the indirect branch in ibt_selftest() as a sibling call, and GCC inserts a (partial) frame pointer prologue before it: 0000 000000000003f550 <ibt_selftest>: 0000 3f550: f3 0f 1e fa endbr64 0004 3f554: e8 00 00 00 00 call 3f559 <ibt_selftest+0x9> 3f555: R_X86_64_PLT32 __fentry__-0x4 0009 3f559: 55 push %rbp 000a 3f55a: 48 8d 05 02 00 00 00 lea 0x2(%rip),%rax # 3f563 <ibt_selftest_ip> 0011 3f561: ff e0 jmp *%rax Note the inline asm is missing ASM_CALL_CONSTRAINT, so the 'push %rbp' happens before the indirect branch and the 'mov %rsp, %rbp' happens afterwards. Simplify the generated code and make it easier to understand for both tools and humans by moving the selftest to proper asm. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/99a7e16b97bda97bf0a04aa141d6241cd8a839a2.1680912949.git.jpoimboe@kernel.org |
|
Ashok Raj
|
82ad097b02 |
x86/microcode: Include vendor headers into microcode.h
Currently vendor specific headers are included explicitly when used in common code. Instead, include the vendor specific headers in microcode.h, and include that in all usages. No functional change. Suggested-by: Boris Petkov <bp@alien8.de> Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230812195727.776541545@linutronix.de |
|
|
Thomas Gleixner
|
3ba3fdfe2c |
x86/cpu: Make identify_boot_cpu() static
It's not longer used outside the source file. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest) |
|
Sebastian Andrzej Siewior
|
80347cd515 |
x86/microcode: Remove microcode_mutex
microcode_mutex is only used by reload_store(). It has a comment saying "to synchronize with each other". Other user of this mutex have been removed in the commits |
|
|
Linus Torvalds
|
64094e7e31 |
Mitigate Gather Data Sampling issue
* Add Base GDS mitigation * Support GDS_NO under KVM * Fix a documentation typo -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEV76QKkVc4xCGURexaDWVMHDJkrAFAmTJh5YACgkQaDWVMHDJ krAzAw/8DzjhAYEa7a1AodCBMNg8uNOPnLNoRPPNhaN5Iw6W3zXYDBDKT9PyjAIx RoIM0aHx/oY9nCpK441o25oCWAAyzk6E5/+q9hMa7B4aHUGKqiDUC6L9dC8UiiSN yvoBv4g7F81QnmyazwYI64S6vnbr4Cqe7K/mvVqQ/vbJiugD25zY8mflRV9YAuMk Oe7Ff/mCA+I/kqyKhJE3cf3qNhZ61FsFI886fOSvIE7g4THKqo5eGPpIQxR4mXiU Ri2JWffTaeHr2m0sAfFeLH4VTZxfAgBkNQUEWeG6f2kDGTEKibXFRsU4+zxjn3gl xug+9jfnKN1ceKyNlVeJJZKAfr2TiyUtrlSE5d+subIRKKBaAGgnCQDasaFAluzd aZkOYz30PCebhN+KTrR84FySHCaxnev04jqdtVGAQEDbTvyNagFUdZFGhWijJShV l2l4A0gFSYJmPfPVuuAwOJnnZtA1sRH9oz/Sny3+z9BKloZh+Nc/+Cu9zC8SLjaU BF3Qv2gU9HKTJ+MSy2JrGS52cONfpO5ngFHoOMilZ1KBHrfSb1eiy32PDT+vK60Y PFEmI8SWl7bmrO1snVUCfGaHBsHJSu5KMqwBGmM4xSRzJpyvRe493xC7+nFvqNLY vFOFc4jGeusOXgiLPpfGduppkTGcM7sy75UMLwTSLcQbDK99mus= =ZAPY -----END PGP SIGNATURE----- Merge tag 'gds-for-linus-2023-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/gds fixes from Dave Hansen: "Mitigate Gather Data Sampling issue: - Add Base GDS mitigation - Support GDS_NO under KVM - Fix a documentation typo" * tag 'gds-for-linus-2023-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Documentation/x86: Fix backwards on/off logic about YMM support KVM: Add GDS_NO support to KVM x86/speculation: Add Kconfig option for GDS x86/speculation: Add force option to GDS mitigation x86/speculation: Add Gather Data Sampling mitigation |
|
|
Linus Torvalds
|
138bcddb86 |
Add a mitigation for the speculative RAS (Return Address Stack) overflow
vulnerability on AMD processors. In short, this is yet another issue where userspace poisons a microarchitectural structure which can then be used to leak privileged information through a side channel. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmTQs1gACgkQEsHwGGHe VUo1UA/8C34PwJveZDcerdkaxSF+WKx7AjOI/L2ws1qn9YVFA3ItFMgVuFTrlY6c 1eYKYB3FS9fVN3KzGOXGyhho6seHqfY0+8cyYupR+PVLn9rSy7GqHaIMr37FdQ2z yb9xu26v+gsvuPEApazS6MxijYS98u71rHhmg97qsHCnUiMJ01+TaGucntukNJv8 FfwjZJvgeUiBPQ/6IeA/O0413tPPJ9weawPyW+sV1w7NlXjaUVkNXwiq/Xxbt9uI sWwMBjFHpSnhBRaDK8W5Blee/ZfsS6qhJ4jyEKUlGtsElMnZLPHbnrbpxxqA9gyE K+3ZhoHf/W1hhvcZcALNoUHLx0CvVekn0o41urAhPfUutLIiwLQWVbApmuW80fgC DhPedEFu7Wp6Okj5+Bqi/XOsOOWN2WRDSzdAq10o1C+e+fzmkr6y4E6gskfz1zXU ssD9S4+uAJ5bccS5lck4zLffsaA03nAYTlvl1KRP4pOz5G9ln6eyO20ar1WwfGAV o5ZsTJVGQMyVA49QFkksj+kOI3chkmDswPYyGn2y8OfqYXU4Ip4eN+VkjorIAo10 zIec3Z0bCGZ9UUMylUmdtH3KAm8q0wVNoFrUkMEmO8j6nn7ew2BhwLMn4uu+nOnw lX2AG6PNhRLVDVaNgDsWMwejaDsitQPoWRuCIAZ0kQhbeYuwfpM= =73JY -----END PGP SIGNATURE----- Merge tag 'x86_bugs_srso' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/srso fixes from Borislav Petkov: "Add a mitigation for the speculative RAS (Return Address Stack) overflow vulnerability on AMD processors. In short, this is yet another issue where userspace poisons a microarchitectural structure which can then be used to leak privileged information through a side channel" * tag 'x86_bugs_srso' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/srso: Tie SBPB bit setting to microcode patch detection x86/srso: Add a forgotten NOENDBR annotation x86/srso: Fix return thunks in generated code x86/srso: Add IBPB on VMEXIT x86/srso: Add IBPB x86/srso: Add SRSO_NO support x86/srso: Add IBPB_BRTYPE support x86/srso: Add a Speculative RAS Overflow mitigation x86/bugs: Increase the x86 bugs vector size to two u32s |
|
Rick Edgecombe
|
0dc2a76092 |
x86/cpufeatures: Enable CET CR4 bit for shadow stack
Setting CR4.CET is a prerequisite for utilizing any CET features, most of which also require setting MSRs. Kernel IBT already enables the CET CR4 bit when it detects IBT HW support and is configured with kernel IBT. However, future patches that enable userspace shadow stack support will need the bit set as well. So change the logic to enable it in either case. Clear MSR_IA32_U_CET in cet_disable() so that it can't live to see userspace in a new kexec-ed kernel that has CR4.CET set from kernel IBT. Co-developed-by: Yu-cheng Yu <yu-cheng.yu@intel.com> Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Mike Rapoport (IBM) <rppt@kernel.org> Tested-by: Pengfei Xu <pengfei.xu@intel.com> Tested-by: John Allen <john.allen@amd.com> Tested-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/all/20230613001108.3040476-39-rick.p.edgecombe%40intel.com |
|
Michael Ellerman
|
447ae4ac41 |
cpu/SMT: Store the current/max number of threads
Some architectures allow partial SMT states at boot time, ie. when not all SMT threads are brought online. To support that the SMT code needs to know the maximum number of SMT threads, and also the currently configured number. The architecture code knows the max number of threads, so have the architecture code pass that value to cpu_smt_set_num_threads(). Note that although topology_max_smt_threads() exists, it is not configured early enough to be used here. As architecture, like PowerPC, allows the threads number to be set through the kernel command line, also pass that value. [ ldufour: Slightly reword the commit message ] [ ldufour: Rename cpu_smt_check_topology and add a num_threads argument ] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Zhang Rui <rui.zhang@intel.com> Link: https://lore.kernel.org/r/20230705145143.40545-5-ldufour@linux.ibm.com |
|
|
Borislav Petkov (AMD)
|
1b5277c0ea |
x86/srso: Add SRSO_NO support
Add support for the CPUID flag which denotes that the CPU is not affected by SRSO. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> |
|
|
Borislav Petkov (AMD)
|
fb3bd914b3 |
x86/srso: Add a Speculative RAS Overflow mitigation
Add a mitigation for the speculative return address stack overflow vulnerability found on AMD processors. The mitigation works by ensuring all RET instructions speculate to a controlled location, similar to how speculation is controlled in the retpoline sequence. To accomplish this, the __x86_return_thunk forces the CPU to mispredict every function return using a 'safe return' sequence. To ensure the safety of this mitigation, the kernel must ensure that the safe return sequence is itself free from attacker interference. In Zen3 and Zen4, this is accomplished by creating a BTB alias between the untraining function srso_untrain_ret_alias() and the safe return function srso_safe_ret_alias() which results in evicting a potentially poisoned BTB entry and using that safe one for all function returns. In older Zen1 and Zen2, this is accomplished using a reinterpretation technique similar to Retbleed one: srso_untrain_ret() and srso_safe_ret(). Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> |
|
Daniel Sneddon
|
8974eb5882 |
x86/speculation: Add Gather Data Sampling mitigation
Gather Data Sampling (GDS) is a hardware vulnerability which allows
unprivileged speculative access to data which was previously stored in
vector registers.
Intel processors that support AVX2 and AVX512 have gather instructions
that fetch non-contiguous data elements from memory. On vulnerable
hardware, when a gather instruction is transiently executed and
encounters a fault, stale data from architectural or internal vector
registers may get transiently stored to the destination vector
register allowing an attacker to infer the stale data using typical
side channel techniques like cache timing attacks.
This mitigation is different from many earlier ones for two reasons.
First, it is enabled by default and a bit must be set to *DISABLE* it.
This is the opposite of normal mitigation polarity. This means GDS can
be mitigated simply by updating microcode and leaving the new control
bit alone.
Second, GDS has a "lock" bit. This lock bit is there because the
mitigation affects the hardware security features KeyLocker and SGX.
It needs to be enabled and *STAY* enabled for these features to be
mitigated against GDS.
The mitigation is enabled in the microcode by default. Disable it by
setting gather_data_sampling=off or by disabling all mitigations with
mitigations=off. The mitigation status can be checked by reading:
/sys/devices/system/cpu/vulnerabilities/gather_data_sampling
Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
|
|
|
Borislav Petkov (AMD)
|
522b1d6921 |
x86/cpu/amd: Add a Zenbleed fix
Add a fix for the Zen2 VZEROUPPER data corruption bug where under certain circumstances executing VZEROUPPER can cause register corruption or leak data. The optimal fix is through microcode but in the case the proper microcode revision has not been applied, enable a fallback fix using a chicken bit. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> |
|
|
Linus Torvalds
|
941d77c773 |
- Compute the purposeful misalignment of zen_untrain_ret automatically
and assert __x86_return_thunk's alignment so that future changes to the symbol macros do not accidentally break them. - Remove CONFIG_X86_FEATURE_NAMES Kconfig option as its existence is pointless -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmSZ1wgACgkQEsHwGGHe VUrXlRAAhIonFM1suIHo6w085jY5YA1XnsziJr/bT3e16FdHrF1i3RBEX4ml0m3O ADwa9dMsC9UJIa+/TKRNFfQvfRcLE/rsUKlS1Rluf/IRIxuSt/Oa4bFQHGXFRwnV eSlnWTNiaWrRs/vJEYAnMOe98oRyElHWa9kZ7K5FC+Ksfn/WO1U1RQ2NWg2A2wkN 8MHJiS41w2piOrLU/nfUoI7+esHgHNlib222LoptDGHuaY8V2kBugFooxAEnTwS3 PCzWUqCTgahs393vbx6JimoIqgJDa7bVdUMB0kOUHxtpbBiNdYYVy6e7UKnV1yjB qP3v9jQW4+xIyRmlFiErJXEZx7DjAIP5nulGRrUMzRfWEGF8mdRZ+ugGqFMHCeC8 vXI+Ixp2vvsfhG3N/algsJUdkjlpt3hBpElRZCfR08M253KAbAmUNMOr4sx4RPi5 ymC+pLIHd1K0G9jiZaFnOMaY71gAzWizwxwjFKLQMo44q+lpNJvsVO00cr+9RBYj LQL2APkONVEzHPMYR/LrXCslYaW//DrfLdRQjNbzUTonxFadkTO2Eu8J90B/5SFZ CqC1NYKMQPVFeg4XuGWCgZEH+jokCGhl8vvmXClAMcOEOZt0/s4H89EKFkmziyon L1ZrA/U72gWV8EwD7GLtuFJmnV4Ayl/hlek2j0qNKaj6UUgTFg8= =LcUq -----END PGP SIGNATURE----- Merge tag 'x86_cpu_for_v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpu updates from Borislav Petkov: - Compute the purposeful misalignment of zen_untrain_ret automatically and assert __x86_return_thunk's alignment so that future changes to the symbol macros do not accidentally break them. - Remove CONFIG_X86_FEATURE_NAMES Kconfig option as its existence is pointless * tag 'x86_cpu_for_v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/retbleed: Add __x86_return_thunk alignment checks x86/cpu: Remove X86_FEATURE_NAMES x86/Kconfig: Make X86_FEATURE_NAMES non-configurable in prompt |
|
|
Linus Torvalds
|
9244724fbf |
A large update for SMP management:
- Parallel CPU bringup
The reason why people are interested in parallel bringup is to shorten
the (kexec) reboot time of cloud servers to reduce the downtime of the
VM tenants.
The current fully serialized bringup does the following per AP:
1) Prepare callbacks (allocate, intialize, create threads)
2) Kick the AP alive (e.g. INIT/SIPI on x86)
3) Wait for the AP to report alive state
4) Let the AP continue through the atomic bringup
5) Let the AP run the threaded bringup to full online state
There are two significant delays:
#3 The time for an AP to report alive state in start_secondary() on
x86 has been measured in the range between 350us and 3.5ms
depending on vendor and CPU type, BIOS microcode size etc.
#4 The atomic bringup does the microcode update. This has been
measured to take up to ~8ms on the primary threads depending on
the microcode patch size to apply.
On a two socket SKL server with 56 cores (112 threads) the boot CPU
spends on current mainline about 800ms busy waiting for the APs to come
up and apply microcode. That's more than 80% of the actual onlining
procedure.
This can be reduced significantly by splitting the bringup mechanism
into two parts:
1) Run the prepare callbacks and kick the AP alive for each AP which
needs to be brought up.
The APs wake up, do their firmware initialization and run the low
level kernel startup code including microcode loading in parallel
up to the first synchronization point. (#1 and #2 above)
2) Run the rest of the bringup code strictly serialized per CPU
(#3 - #5 above) as it's done today.
Parallelizing that stage of the CPU bringup might be possible in
theory, but it's questionable whether required surgery would be
justified for a pretty small gain.
If the system is large enough the first AP is already waiting at the
first synchronization point when the boot CPU finished the wake-up of
the last AP. That reduces the AP bringup time on that SKL from ~800ms
to ~80ms, i.e. by a factor ~10x.
The actual gain varies wildly depending on the system, CPU, microcode
patch size and other factors. There are some opportunities to reduce
the overhead further, but that needs some deep surgery in the x86 CPU
bringup code.
For now this is only enabled on x86, but the core functionality
obviously works for all SMP capable architectures.
- Enhancements for SMP function call tracing so it is possible to locate
the scheduling and the actual execution points. That allows to measure
IPI delivery time precisely.
-----BEGIN PGP SIGNATURE-----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=Y8if
-----END PGP SIGNATURE-----
Merge tag 'smp-core-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull SMP updates from Thomas Gleixner:
"A large update for SMP management:
- Parallel CPU bringup
The reason why people are interested in parallel bringup is to
shorten the (kexec) reboot time of cloud servers to reduce the
downtime of the VM tenants.
The current fully serialized bringup does the following per AP:
1) Prepare callbacks (allocate, intialize, create threads)
2) Kick the AP alive (e.g. INIT/SIPI on x86)
3) Wait for the AP to report alive state
4) Let the AP continue through the atomic bringup
5) Let the AP run the threaded bringup to full online state
There are two significant delays:
#3 The time for an AP to report alive state in start_secondary()
on x86 has been measured in the range between 350us and 3.5ms
depending on vendor and CPU type, BIOS microcode size etc.
#4 The atomic bringup does the microcode update. This has been
measured to take up to ~8ms on the primary threads depending
on the microcode patch size to apply.
On a two socket SKL server with 56 cores (112 threads) the boot CPU
spends on current mainline about 800ms busy waiting for the APs to
come up and apply microcode. That's more than 80% of the actual
onlining procedure.
This can be reduced significantly by splitting the bringup
mechanism into two parts:
1) Run the prepare callbacks and kick the AP alive for each AP
which needs to be brought up.
The APs wake up, do their firmware initialization and run the
low level kernel startup code including microcode loading in
parallel up to the first synchronization point. (#1 and #2
above)
2) Run the rest of the bringup code strictly serialized per CPU
(#3 - #5 above) as it's done today.
Parallelizing that stage of the CPU bringup might be possible
in theory, but it's questionable whether required surgery
would be justified for a pretty small gain.
If the system is large enough the first AP is already waiting at
the first synchronization point when the boot CPU finished the
wake-up of the last AP. That reduces the AP bringup time on that
SKL from ~800ms to ~80ms, i.e. by a factor ~10x.
The actual gain varies wildly depending on the system, CPU,
microcode patch size and other factors. There are some
opportunities to reduce the overhead further, but that needs some
deep surgery in the x86 CPU bringup code.
For now this is only enabled on x86, but the core functionality
obviously works for all SMP capable architectures.
- Enhancements for SMP function call tracing so it is possible to
locate the scheduling and the actual execution points. That allows
to measure IPI delivery time precisely"
* tag 'smp-core-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip: (45 commits)
trace,smp: Add tracepoints for scheduling remotelly called functions
trace,smp: Add tracepoints around remotelly called functions
MAINTAINERS: Add CPU HOTPLUG entry
x86/smpboot: Fix the parallel bringup decision
x86/realmode: Make stack lock work in trampoline_compat()
x86/smp: Initialize cpu_primary_thread_mask late
cpu/hotplug: Fix off by one in cpuhp_bringup_mask()
x86/apic: Fix use of X{,2}APIC_ENABLE in asm with older binutils
x86/smpboot/64: Implement arch_cpuhp_init_parallel_bringup() and enable it
x86/smpboot: Support parallel startup of secondary CPUs
x86/smpboot: Implement a bit spinlock to protect the realmode stack
x86/apic: Save the APIC virtual base address
cpu/hotplug: Allow "parallel" bringup up to CPUHP_BP_KICK_AP_STATE
x86/apic: Provide cpu_primary_thread mask
x86/smpboot: Enable split CPU startup
cpu/hotplug: Provide a split up CPUHP_BRINGUP mechanism
cpu/hotplug: Reset task stack state in _cpu_up()
cpu/hotplug: Remove unused state functions
riscv: Switch to hotplug core state synchronization
parisc: Switch to hotplug core state synchronization
...
|
|
|
Thomas Gleixner
|
b81fac906a |
x86/fpu: Move FPU initialization into arch_cpu_finalize_init()
Initializing the FPU during the early boot process is a pointless exercise. Early boot is convoluted and fragile enough. Nothing requires that the FPU is set up early. It has to be initialized before fork_init() because the task_struct size depends on the FPU register buffer size. Move the initialization to arch_cpu_finalize_init() which is the perfect place to do so. No functional change. This allows to remove quite some of the custom early command line parsing, but that's subject to the next installment. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230613224545.902376621@linutronix.de |
|
|
Thomas Gleixner
|
1f34bb2a24 |
x86/fpu: Remove cpuinfo argument from init functions
Nothing in the call chain requires it Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230613224545.783704297@linutronix.de |
|
|
Thomas Gleixner
|
54d9a91a3d |
x86/init: Initialize signal frame size late
No point in doing this during really early boot. Move it to an early initcall so that it is set up before possible user mode helpers are started during device initialization. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230613224545.727330699@linutronix.de |
|
|
Thomas Gleixner
|
439e17576e |
init, x86: Move mem_encrypt_init() into arch_cpu_finalize_init()
Invoke the X86ism mem_encrypt_init() from X86 arch_cpu_finalize_init() and remove the weak fallback from the core code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20230613224545.670360645@linutronix.de |
|
|
Thomas Gleixner
|
7c7077a726 |
x86/cpu: Switch to arch_cpu_finalize_init()
check_bugs() is a dumping ground for finalizing the CPU bringup. Only parts of it has to do with actual CPU bugs. Split it apart into arch_cpu_finalize_init() and cpu_select_mitigations(). Fixup the bogus 32bit comments while at it. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230613224545.019583869@linutronix.de |
|
Lukas Bulwahn
|
7583e8fbdc |
x86/cpu: Remove X86_FEATURE_NAMES
While discussing to change the visibility of X86_FEATURE_NAMES (see Link) in order to remove CONFIG_EMBEDDED, Boris suggested to simply make the X86_FEATURE_NAMES functionality unconditional. As the need for really tiny kernel images has gone away and kernel images with !X86_FEATURE_NAMES are hardly tested, remove this config and the whole ifdeffery in the source code. Suggested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/all/20230509084007.24373-1-lukas.bulwahn@gmail.com/ Link: https://lore.kernel.org/r/20230510065713.10996-3-lukas.bulwahn@gmail.com |
|
|
Thomas Gleixner
|
0c7ffa32db |
x86/smpboot/64: Implement arch_cpuhp_init_parallel_bringup() and enable it
Implement the validation function which tells the core code whether parallel bringup is possible. The only condition for now is that the kernel does not run in an encrypted guest as these will trap the RDMSR via #VC, which cannot be handled at that point in early startup. There was an earlier variant for AMD-SEV which used the GHBC protocol for retrieving the APIC ID via CPUID, but there is no guarantee that the initial APIC ID in CPUID is the same as the real APIC ID. There is no enforcement from the secure firmware and the hypervisor can assign APIC IDs as it sees fit as long as the ACPI/MADT table is consistent with that assignment. Unfortunately there is no RDMSR GHCB protocol at the moment, so enabling AMD-SEV guests for parallel startup needs some more thought. Intel-TDX provides a secure RDMSR hypercall, but supporting that is outside the scope of this change. Fixup announce_cpu() as e.g. on Hyper-V CPU1 is the secondary sibling of CPU0, which makes the @cpu == 1 logic in announce_cpu() fall apart. [ mikelley: Reported the announce_cpu() fallout Originally-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205257.467571745@linutronix.de |
|
|
Thomas Gleixner
|
d4f28f07c2 |
x86/smpboot: Move synchronization masks to SMP boot code
The usage is in smpboot.c and not in the CPU initialization code. The XEN_PV usage of cpu_callout_mask is obsolete as cpu_init() not longer waits and cacheinfo has its own CPU mask now, so cpu_callout_mask can be made static too. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205256.091511483@linutronix.de |
|
|
Thomas Gleixner
|
e94cd1503b |
x86/smpboot: Get rid of cpu_init_secondary()
The synchronization of the AP with the control CPU is a SMP boot problem and has nothing to do with cpu_init(). Open code cpu_init_secondary() in start_secondary() and move wait_for_master_cpu() into the SMP boot code. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205255.981999763@linutronix.de |
|
|
Tony Luck
|
36168bc061 |
x86/cpu: Add Xeon Emerald Rapids to list of CPUs that support PPIN
This should be the last addition to this table. Future CPUs will enumerate PPIN support using CPUID. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230404212124.428118-1-tony.luck@intel.com |
|
|
Linus Torvalds
|
06e1a81c48 |
A healthy mix of EFI contributions this time:
- Performance tweaks for efifb earlycon by Andy
- Preparatory refactoring and cleanup work in the efivar layer by Johan,
which is needed to accommodate the Snapdragon arm64 laptops that
expose their EFI variable store via a TEE secure world API.
- Enhancements to the EFI memory map handling so that Xen dom0 can
safely access EFI configuration tables (Demi Marie)
- Wire up the newly introduced IBT/BTI flag in the EFI memory attributes
table, so that firmware that is generated with ENDBR/BTI landing pads
will be mapped with enforcement enabled.
- Clean up how we check and print the EFI revision exposed by the
firmware.
- Incorporate EFI memory attributes protocol definition contributed by
Evgeniy and wire it up in the EFI zboot code. This ensures that these
images can execute under new and stricter rules regarding the default
memory permissions for EFI page allocations. (More work is in progress
here)
- CPER header cleanup by Dan Williams
- Use a raw spinlock to protect the EFI runtime services stack on arm64
to ensure the correct semantics under -rt. (Pierre)
- EFI framebuffer quirk for Lenovo Ideapad by Darrell.
-----BEGIN PGP SIGNATURE-----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=+pOz
-----END PGP SIGNATURE-----
Merge tag 'efi-next-for-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi
Pull EFI updates from Ard Biesheuvel:
"A healthy mix of EFI contributions this time:
- Performance tweaks for efifb earlycon (Andy)
- Preparatory refactoring and cleanup work in the efivar layer, which
is needed to accommodate the Snapdragon arm64 laptops that expose
their EFI variable store via a TEE secure world API (Johan)
- Enhancements to the EFI memory map handling so that Xen dom0 can
safely access EFI configuration tables (Demi Marie)
- Wire up the newly introduced IBT/BTI flag in the EFI memory
attributes table, so that firmware that is generated with ENDBR/BTI
landing pads will be mapped with enforcement enabled
- Clean up how we check and print the EFI revision exposed by the
firmware
- Incorporate EFI memory attributes protocol definition and wire it
up in the EFI zboot code (Evgeniy)
This ensures that these images can execute under new and stricter
rules regarding the default memory permissions for EFI page
allocations (More work is in progress here)
- CPER header cleanup (Dan Williams)
- Use a raw spinlock to protect the EFI runtime services stack on
arm64 to ensure the correct semantics under -rt (Pierre)
- EFI framebuffer quirk for Lenovo Ideapad (Darrell)"
* tag 'efi-next-for-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: (24 commits)
firmware/efi sysfb_efi: Add quirk for Lenovo IdeaPad Duet 3
arm64: efi: Make efi_rt_lock a raw_spinlock
efi: Add mixed-mode thunk recipe for GetMemoryAttributes
efi: x86: Wire up IBT annotation in memory attributes table
efi: arm64: Wire up BTI annotation in memory attributes table
efi: Discover BTI support in runtime services regions
efi/cper, cxl: Remove cxl_err.h
efi: Use standard format for printing the EFI revision
efi: Drop minimum EFI version check at boot
efi: zboot: Use EFI protocol to remap code/data with the right attributes
efi/libstub: Add memory attribute protocol definitions
efi: efivars: prevent double registration
efi: verify that variable services are supported
efivarfs: always register filesystem
efi: efivars: add efivars printk prefix
efi: Warn if trying to reserve memory under Xen
efi: Actually enable the ESRT under Xen
efi: Apply allowlist to EFI configuration tables when running under Xen
efi: xen: Implement memory descriptor lookup based on hypercall
efi: memmap: Disregard bogus entries instead of returning them
...
|
|
|
Linus Torvalds
|
877934769e |
- Cache the AMD debug registers in per-CPU variables to avoid MSR writes
where possible, when supporting a debug registers swap feature for SEV-ES guests - Add support for AMD's version of eIBRS called Automatic IBRS which is a set-and-forget control of indirect branch restriction speculation resources on privilege change - Add support for a new x86 instruction - LKGS - Load kernel GS which is part of the FRED infrastructure - Reset SPEC_CTRL upon init to accomodate use cases like kexec which rediscover - Other smaller fixes and cleanups -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmP1RDIACgkQEsHwGGHe VUohBw//ZB9ZRqsrKdm6D9YaP2x4Zb+kqKqo6rjYeWaYqyPyCwDujPwh+pb3Oq1t aj62muDv1t/wEJc8mKNkfXkjEEtBVAOcpb5YIpKreoEvNKyevol83Ih0u5iJcTRE E5qf8HDS8b/JZrcazJJLl6WQmQNH5RiKSu5bbCpRhoeOcyo5pRYR5MztK9vNmAQk GMdwHsUSU+jN8uiE4HnpaOb/luhgFindRwZVTpdjJegQWLABS8cl3CKeTv4+PW45 isvv37XnQP248wsptIEVRHeG6g3g/HtvwRx7DikUw06QwUyUK7H9hJssOoSP8TL9 u4psRwfWnJ1OxU6klL+s0Ii+pjQ97wXmK/oqK7QkdUwhWqR/mQAW2e9kWHAngyDn A6mKbzSM6HFAeSXQpB9cMb6uvYRD44SngDFe3WXtEK8jiiQ70ikUm4E28I5KJOPg s+RyioHk0NFRHYSOOBqNG1NKz6ED7L3GbgbbzxkgMh21AAyI3X351t+PtGoLV5ew eqOsM7lbg9Scg1LvPk1JcoALS8USWqgar397rz9qGUs+OkPWBtEBCmTdMz/Eb+2t g/WHdLS5/ajSs5gNhT99W3DeqZMPDEkgBRSeyBBmY3CUD3gBL2wXEktRXv504zBR RC4oyUPX3c9E2ib6GATLE3kBLbcz9hTWbMxF+X3lLJvTVd/Qc2o= =v/ZC -----END PGP SIGNATURE----- Merge tag 'x86_cpu_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpuid updates from Borislav Petkov: - Cache the AMD debug registers in per-CPU variables to avoid MSR writes where possible, when supporting a debug registers swap feature for SEV-ES guests - Add support for AMD's version of eIBRS called Automatic IBRS which is a set-and-forget control of indirect branch restriction speculation resources on privilege change - Add support for a new x86 instruction - LKGS - Load kernel GS which is part of the FRED infrastructure - Reset SPEC_CTRL upon init to accomodate use cases like kexec which rediscover - Other smaller fixes and cleanups * tag 'x86_cpu_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/amd: Cache debug register values in percpu variables KVM: x86: Propagate the AMD Automatic IBRS feature to the guest x86/cpu: Support AMD Automatic IBRS x86/cpu, kvm: Add the SMM_CTL MSR not present feature x86/cpu, kvm: Add the Null Selector Clears Base feature x86/cpu, kvm: Move X86_FEATURE_LFENCE_RDTSC to its native leaf x86/cpu, kvm: Add the NO_NESTED_DATA_BP feature KVM: x86: Move open-coded CPUID leaf 0x80000021 EAX bit propagation code x86/cpu, kvm: Add support for CPUID_80000021_EAX x86/gsseg: Add the new <asm/gsseg.h> header to <asm/asm-prototypes.h> x86/gsseg: Use the LKGS instruction if available for load_gs_index() x86/gsseg: Move load_gs_index() to its own new header file x86/gsseg: Make asm_load_gs_index() take an u16 x86/opcode: Add the LKGS instruction to x86-opcode-map x86/cpufeature: Add the CPU feature bit for LKGS x86/bugs: Reset speculation control settings on init x86/cpu: Remove redundant extern x86_read_arch_cap_msr() |
|
|
Linus Torvalds
|
056612fd41 |
Miscellaneous cleanups in X86:
- Correct the common copy and pasted mishandling of kstrtobool() in the
strict_sas_size() setup function.
- Make recalibrate_cpu_khz() an GPL only export.
- Check TSC feature before doing anything else which avoids pointless
code execution if TSC is not available.
- Remove or fixup stale and misleading comments.
- Remove unused or pointelessly duplicated variables.
- Spelling and typo fixes.
-----BEGIN PGP SIGNATURE-----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=zlRy
-----END PGP SIGNATURE-----
Merge tag 'x86-cleanups-2023-02-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull miscellaneous x86 cleanups from Thomas Gleixner:
- Correct the common copy and pasted mishandling of kstrtobool() in the
strict_sas_size() setup function
- Make recalibrate_cpu_khz() an GPL only export
- Check TSC feature before doing anything else which avoids pointless
code execution if TSC is not available
- Remove or fixup stale and misleading comments
- Remove unused or pointelessly duplicated variables
- Spelling and typo fixes
* tag 'x86-cleanups-2023-02-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/hotplug: Remove incorrect comment about mwait_play_dead()
x86/tsc: Do feature check as the very first thing
x86/tsc: Make recalibrate_cpu_khz() export GPL only
x86/cacheinfo: Remove unused trace variable
x86/Kconfig: Fix spellos & punctuation
x86/signal: Fix the value returned by strict_sas_size()
x86/cpu: Remove misleading comment
x86/setup: Move duplicate boot_cpu_data definition out of the ifdeffery
x86/boot/e820: Fix typo in e820.c comment
|
|
|
Linus Torvalds
|
3f0b0903fd |
- Add getcpu support for the 32-bit version of the vDSO
- Some smaller fixes -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmPzusMACgkQEsHwGGHe VUojfQ/7BOqXI0XsHTIwilF12w2bLQl1PeI4bSk6VY+iAN2YmQkq2qvNUgwt62e5 5Z95cDuCZ8sx6L3mDIoOgWBN9zdLbxNhezLFDykb+6as67PMaww9l9R6n3JoC2qm ELso5JZnWvIZ7Cu7RRm9IzbSj93JAlN3Aypexe61NywMyge9CAvCiOEhvW+lkYSD lhZqgbm5WAB14F1CeqFyC8kVvUez1GH9Dunbe7ozk7LqRfTRlf5YPH88iE4UKzdg JXmbcHB2K4aQzfIW66OFPnl/4Cl+XxS/i5CR2NtWlB4/ANZBPoUr7QAS239OpC6u 3uwv/qPmMe7p/lYMaGXSUpzD/MOCHP1HPN8/CWgdyK+Mdmctpqr0FYh1qXXm1Nuu v0SE3btHVIB5UfvImoOlV/RfCx3+TqxzqUU2erc0iD5VxlRfrqJEwJdJHOgRGxFU vflRxMQOshhyI7+Q7et0S0QlgK4HvGEHmBUwBsUbfyptIxbqpOLK8INC6N8qwGKZ gTuBxLNZ5yRE/NeOVe0cL2ooelfOlg7GKUI+gZbfzzQw8M5WZW9qEDS9y2wIuGey wBFJNzjKXSkrTxc6Hd136N7DX7PlMjiJhXP42s+7rXJguPvgk1oVyEuaX540+xX4 HphXRC2QW0o0hCeFgP11Ai4oq/vRW1RFvdDimJjveJAv19bQNv0= =Wg/8 -----END PGP SIGNATURE----- Merge tag 'x86_vdso_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 vdso updates from Borislav Petkov: - Add getcpu support for the 32-bit version of the vDSO - Some smaller fixes * tag 'x86_vdso_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/vdso: Fix -Wmissing-prototypes warnings x86/vdso: Fake 32bit VDSO build on 64bit compile for vgetcpu selftests: Emit a warning if getcpu() is missing on 32bit x86/vdso: Provide getcpu for x86-32. x86/cpu: Provide the full setup for getcpu() on x86-32 x86/vdso: Move VDSO image init to vdso2c generated code |
|
|
Linus Torvalds
|
efebca0ba9 |
- Fix mixed steppings support on AMD which got broken somewhere along
the way - Improve revision reporting - Properly check CPUID capabilities after late microcode upgrade to avoid false positives - A garden variety of other small fixes -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmPzs/sACgkQEsHwGGHe VUonGw//RgIVCZIkuytiZesFsAXD3sn4Mmji7WoRZvu3XooA0idOo+7ujBeNcJGw aFGjf0K5b7eAfiREqTXPlFSymPid7aN+7cPJD7iURJ5UEoDXca1vVh9Jeq7lhvRL M5CErroStya17vFqU5pz50EcUwGcao/N3wY+0rERk8Rkqu864PgI+KahS2V2D2PU XolD4CH/+JZMAJPaTG5dSkSf3gJevW/owZ+F2oqKKYNlFsQ6aYd/JZYwIQ2X7W9T HdVYzeASZs0tfBEPOsZUSobmIlqUU/MziefDyUuTYbO1DPJ525787RLpRyubhG9k b/7DWUNymR56B8AUq/RV6YE/Dw2YpcrP3Eu0pSbD5xUfEy8eFCcIr+cUL5M9+I4W iCZtYYGypNbDQf5NRkubtQu8xIwEbjOZNv444kMMBimZGzt/WDEGMHqgRbKpJ2MQ F2HoBnNVC5O2BddS0ErTpQDWK8B/c0+S4L1ZTkbh/y9CNhzITZ10sLAEGQawvBEk PBYeCQ98m72ijLcecz0vvVO81UHGicqyY86OqeqRx0FbGO9cZJg+8BqyTLxsRTSW OgxtB/moURdanWAAOdxZ91yUw40CYWn7qXhYxilZDtGgkFT6sUdA126uMxLJ8u2v WiOHmj/ymszHhkJiahcSMaD8gRFnLQ59jNatHNa/5Jyw0mi330g= =z8rd -----END PGP SIGNATURE----- Merge tag 'x86_microcode_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode loader updates from Borislav Petkov: - Fix mixed steppings support on AMD which got broken somewhere along the way - Improve revision reporting - Properly check CPUID capabilities after late microcode upgrade to avoid false positives - A garden variety of other small fixes * tag 'x86_microcode_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode/core: Return an error only when necessary x86/microcode/AMD: Fix mixed steppings support x86/microcode/AMD: Add a @cpu parameter to the reloading functions x86/microcode/amd: Remove load_microcode_amd()'s bsp parameter x86/microcode: Allow only "1" as a late reload trigger value x86/microcode/intel: Print old and new revision during early boot x86/microcode/intel: Pass the microcode revision to print_ucode_info() directly x86/microcode: Adjust late loading result reporting message x86/microcode: Check CPU capabilities after late microcode update correctly x86/microcode: Add a parameter to microcode_check() to store CPU capabilities x86/microcode: Use the DEVICE_ATTR_RO() macro x86/microcode/AMD: Handle multiple glued containers properly x86/microcode/AMD: Rename a couple of functions |
|
Tom Lendacky
|
be8de49bea |
x86/speculation: Identify processors vulnerable to SMT RSB predictions
Certain AMD processors are vulnerable to a cross-thread return address predictions bug. When running in SMT mode and one of the sibling threads transitions out of C0 state, the other sibling thread could use return target predictions from the sibling thread that transitioned out of C0. The Spectre v2 mitigations cover the Linux kernel, as it fills the RSB when context switching to the idle thread. However, KVM allows a VMM to prevent exiting guest mode when transitioning out of C0. A guest could act maliciously in this situation, so create a new x86 BUG that can be used to detect if the processor is vulnerable. Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Message-Id: <91cec885656ca1fcd4f0185ce403a53dd9edecb7.1675956146.git.thomas.lendacky@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
|
Ard Biesheuvel
|
93be2859e2 |
efi: x86: Wire up IBT annotation in memory attributes table
UEFI v2.10 extends the EFI memory attributes table with a flag that indicates whether or not all RuntimeServicesCode regions were constructed with ENDBR landing pads, permitting the OS to map these regions with IBT restrictions enabled. So let's take this into account on x86 as well. Suggested-by: Peter Zijlstra <peterz@infradead.org> # ibt_save() changes Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> |
|
|
Sebastian Andrzej Siewior
|
717cce3bdc |
x86/cpu: Provide the full setup for getcpu() on x86-32
setup_getcpu() configures two things: - it writes the current CPU & node information into MSR_TSC_AUX - it writes the same information as a GDT entry. By using the "full" setup_getcpu() on i386 it is possible to read the CPU information in userland via RDTSCP() or via LSL from the GDT. Provide an GDT_ENTRY_CPUNODE for x86-32 and make the setup function unconditionally available. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Roland Mainz <roland.mainz@nrubsig.org> Link: https://lore.kernel.org/r/20221125094216.3663444-2-bigeasy@linutronix.de |
|
|
Kim Phillips
|
e7862eda30 |
x86/cpu: Support AMD Automatic IBRS
The AMD Zen4 core supports a new feature called Automatic IBRS. It is a "set-and-forget" feature that means that, like Intel's Enhanced IBRS, h/w manages its IBRS mitigation resources automatically across CPL transitions. The feature is advertised by CPUID_Fn80000021_EAX bit 8 and is enabled by setting MSR C000_0080 (EFER) bit 21. Enable Automatic IBRS by default if the CPU feature is present. It typically provides greater performance over the incumbent generic retpolines mitigation. Reuse the SPECTRE_V2_EIBRS spectre_v2_mitigation enum. AMD Automatic IBRS and Intel Enhanced IBRS have similar enablement. Add NO_EIBRS_PBRSB to cpu_vuln_whitelist, since AMD Automatic IBRS isn't affected by PBRSB-eIBRS. The kernel command line option spectre_v2=eibrs is used to select AMD Automatic IBRS, if available. Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Sean Christopherson <seanjc@google.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/r/20230124163319.2277355-8-kim.phillips@amd.com |