mirror of https://github.com/torvalds/linux.git
22 Commits
| Author | SHA1 | Message | Date |
|---|---|---|---|
Pasha Tatashin
|
e38f65d317 |
kho: warn and fail on metadata or preserved memory in scratch area
Patch series "KHO: kfence + KHO memory corruption fix", v3.
This series fixes a memory corruption bug in KHO that occurs when KFENCE
is enabled.
The root cause is that KHO metadata, allocated via kzalloc(), can be
randomly serviced by kfence_alloc(). When a kernel boots via KHO, the
early memblock allocator is restricted to a "scratch area". This forces
the KFENCE pool to be allocated within this scratch area, creating a
conflict. If KHO metadata is subsequently placed in this pool, it gets
corrupted during the next kexec operation.
Google is using KHO and have had obscure crashes due to this memory
corruption, with stacks all over the place. I would prefer this fix to be
properly backported to stable so we can also automatically consume it once
we switch to the upstream KHO.
Patch 1/3 introduces a debug-only feature (CONFIG_KEXEC_HANDOVER_DEBUG)
that adds checks to detect and fail any operation that attempts to place
KHO metadata or preserved memory within the scratch area. This serves as
a validation and diagnostic tool to confirm the problem without affecting
production builds.
Patch 2/3 Increases bitmap to PAGE_SIZE, so buddy allocator can be used.
Patch 3/3 Provides the fix by modifying KHO to allocate its metadata
directly from the buddy allocator instead of slab. This bypasses the
KFENCE interception entirely.
This patch (of 3):
It is invalid for KHO metadata or preserved memory regions to be located
within the KHO scratch area, as this area is overwritten when the next
kernel is loaded, and used early in boot by the next kernel. This can
lead to memory corruption.
Add checks to kho_preserve_* and KHO's internal metadata allocators
(xa_load_or_alloc, new_chunk) to verify that the physical address of the
memory does not overlap with any defined scratch region. If an overlap is
detected, the operation will fail and a WARN_ON is triggered. To avoid
performance overhead in production kernels, these checks are enabled only
when CONFIG_KEXEC_HANDOVER_DEBUG is selected.
[rppt@kernel.org: fix KEXEC_HANDOVER_DEBUG Kconfig dependency]
Link: https://lkml.kernel.org/r/aQHUyyFtiNZhx8jo@kernel.org
[pasha.tatashin@soleen.com: build fix]
Link: https://lkml.kernel.org/r/CA+CK2bBnorfsTymKtv4rKvqGBHs=y=MjEMMRg_tE-RME6n-zUw@mail.gmail.com
Link: https://lkml.kernel.org/r/20251021000852.2924827-1-pasha.tatashin@soleen.com
Link: https://lkml.kernel.org/r/20251021000852.2924827-2-pasha.tatashin@soleen.com
Fixes:
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Mike Rapoport (Microsoft)
|
a667300bd5 |
kho: add support for preserving vmalloc allocations
A vmalloc allocation is preserved using binary structure similar to global KHO memory tracker. It's a linked list of pages where each page is an array of physical address of pages in vmalloc area. kho_preserve_vmalloc() hands out the physical address of the head page to the caller. This address is used as the argument to kho_vmalloc_restore() to restore the mapping in the vmalloc address space and populate it with the preserved pages. [pasha.tatashin@soleen.com: free chunks using free_page() not kfree()] Link: https://lkml.kernel.org/r/mafs0a52idbeg.fsf@kernel.org [akpm@linux-foundation.org: coding-style cleanups] Link: https://lkml.kernel.org/r/20250921054458.4043761-4-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Pratyush Yadav <pratyush@kernel.org> Cc: Alexander Graf <graf@amazon.com> Cc: Baoquan He <bhe@redhat.com> Cc: Changyuan Lyu <changyuanl@google.com> Cc: Chris Li <chrisl@kernel.org> Cc: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Mike Rapoport (Microsoft)
|
8375b76517 |
kho: replace kho_preserve_phys() with kho_preserve_pages()
to make it clear that KHO operates on pages rather than on a random physical address. The kho_preserve_pages() will be also used in upcoming support for vmalloc preservation. Link: https://lkml.kernel.org/r/20250921054458.4043761-3-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Pratyush Yadav <pratyush@kernel.org> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Graf <graf@amazon.com> Cc: Baoquan He <bhe@redhat.com> Cc: Changyuan Lyu <changyuanl@google.com> Cc: Chris Li <chrisl@kernel.org> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Mike Rapoport (Microsoft)
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469661d0d3 |
kho: check if kho is finalized in __kho_preserve_order()
Patch series "kho: add support for preserving vmalloc allocations", v5.
Following the discussion about preservation of memfd with LUO [1] these
patches add support for preserving vmalloc allocations.
Any KHO uses case presumes that there's a data structure that lists
physical addresses of preserved folios (and potentially some additional
metadata). Allowing vmalloc preservations with KHO allows scalable
preservation of such data structures.
For instance, instead of allocating array describing preserved folios in
the fdt, memfd preservation can use vmalloc:
preserved_folios = vmalloc_array(nr_folios, sizeof(*preserved_folios));
memfd_luo_preserve_folios(preserved_folios, folios, nr_folios);
kho_preserve_vmalloc(preserved_folios, &folios_info);
This patch (of 4):
Instead of checking if kho is finalized in each caller of
__kho_preserve_order(), do it in the core function itself.
Link: https://lkml.kernel.org/r/20250921054458.4043761-1-rppt@kernel.org
Link: https://lkml.kernel.org/r/20250921054458.4043761-2-rppt@kernel.org
Link: https://lore.kernel.org/all/20250807014442.3829950-30-pasha.tatashin@soleen.com [1]
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Cc: Alexander Graf <graf@amazon.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Changyuan Lyu <changyuanl@google.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Linus Torvalds
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e406d57be7 |
Patch series in this pull request:
- The 3 patch series "ida: Remove the ida_simple_xxx() API" from Christophe Jaillet completes the removal of this legacy IDR API. - The 9 patch series "panic: introduce panic status function family" from Jinchao Wang provides a number of cleanups to the panic code and its various helpers, which were rather ad-hoc and scattered all over the place. - The 5 patch series "tools/delaytop: implement real-time keyboard interaction support" from Fan Yu adds a few nice user-facing usability changes to the delaytop monitoring tool. - The 3 patch series "efi: Fix EFI boot with kexec handover (KHO)" from Evangelos Petrongonas fixes a panic which was happening with the combination of EFI and KHO. - The 2 patch series "Squashfs: performance improvement and a sanity check" from Phillip Lougher teaches squashfs's lseek() about SEEK_DATA/SEEK_HOLE. A mere 150x speedup was measured for a well-chosen microbenchmark. - Plus another 50-odd singleton patches all over the place. -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaN78zwAKCRDdBJ7gKXxA jhLeAQCddTv0XtSUTrvBvmrJVUBrQQeJc+LtNopMIjfAF/WAWAEAogSVKxg+HHEB GaVixx4zDriNzEqrqiCx9rm4l+YooQA= =XRe0 -----END PGP SIGNATURE----- Merge tag 'mm-nonmm-stable-2025-10-02-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: - "ida: Remove the ida_simple_xxx() API" from Christophe Jaillet completes the removal of this legacy IDR API - "panic: introduce panic status function family" from Jinchao Wang provides a number of cleanups to the panic code and its various helpers, which were rather ad-hoc and scattered all over the place - "tools/delaytop: implement real-time keyboard interaction support" from Fan Yu adds a few nice user-facing usability changes to the delaytop monitoring tool - "efi: Fix EFI boot with kexec handover (KHO)" from Evangelos Petrongonas fixes a panic which was happening with the combination of EFI and KHO - "Squashfs: performance improvement and a sanity check" from Phillip Lougher teaches squashfs's lseek() about SEEK_DATA/SEEK_HOLE. A mere 150x speedup was measured for a well-chosen microbenchmark - plus another 50-odd singleton patches all over the place * tag 'mm-nonmm-stable-2025-10-02-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (75 commits) Squashfs: reject negative file sizes in squashfs_read_inode() kallsyms: use kmalloc_array() instead of kmalloc() MAINTAINERS: update Sibi Sankar's email address Squashfs: add SEEK_DATA/SEEK_HOLE support Squashfs: add additional inode sanity checking lib/genalloc: fix device leak in of_gen_pool_get() panic: remove CONFIG_PANIC_ON_OOPS_VALUE ocfs2: fix double free in user_cluster_connect() checkpatch: suppress strscpy warnings for userspace tools cramfs: fix incorrect physical page address calculation kernel: prevent prctl(PR_SET_PDEATHSIG) from racing with parent process exit Squashfs: fix uninit-value in squashfs_get_parent kho: only fill kimage if KHO is finalized ocfs2: avoid extra calls to strlen() after ocfs2_sprintf_system_inode_name() kernel/sys.c: fix the racy usage of task_lock(tsk->group_leader) in sys_prlimit64() paths sched/task.h: fix the wrong comment on task_lock() nesting with tasklist_lock coccinelle: platform_no_drv_owner: handle also built-in drivers coccinelle: of_table: handle SPI device ID tables lib/decompress: use designated initializers for struct compress_format efi: support booting with kexec handover (KHO) ... |
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Pratyush Yadav
|
f322a97aeb |
kho: only fill kimage if KHO is finalized
kho_fill_kimage() only checks for KHO being enabled before filling in the
FDT to the image. KHO being enabled does not mean that the kernel has
data to hand over. That happens when KHO is finalized.
When a kexec is done with KHO enabled but not finalized, the FDT page is
allocated but not initialized. FDT initialization happens after finalize.
This means the KHO segment is filled in but the FDT contains garbage
data.
This leads to the below error messages in the next kernel:
[ 0.000000] KHO: setup: handover FDT (0x10116b000) is invalid: -9
[ 0.000000] KHO: disabling KHO revival: -22
There is no problem in practice, and the next kernel boots and works fine.
But this still leads to misleading error messages and garbage being
handed over.
Only fill in KHO segment when KHO is finalized. When KHO is not enabled,
the debugfs interface is not created and there is no way to finalize it
anyway. So the check for kho_enable is not needed, and kho_out.finalize
alone is enough.
Link: https://lkml.kernel.org/r/20250918170617.91413-1-pratyush@kernel.org
Fixes:
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Pratyush Yadav
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89a3ecca49 |
kho: make sure page being restored is actually from KHO
When restoring a page, no sanity checks are done to make sure the page actually came from a kexec handover. The caller is trusted to pass in the right address. If the caller has a bug and passes in a wrong address, an in-use page might be "restored" and returned, causing all sorts of memory corruption. Harden the page restore logic by stashing in a magic number in page->private along with the order. If the magic number does not match, the page won't be touched. page->private is an unsigned long. The union kho_page_info splits it into two parts, with one holding the order and the other holding the magic number. Link: https://lkml.kernel.org/r/20250917125725.665-2-pratyush@kernel.org Signed-off-by: Pratyush Yadav <pratyush@kernel.org> Cc: Alexander Graf <graf@amazon.com> Cc: Baoquan He <bhe@redhat.com> Cc: Changyuan Lyu <changyuanl@google.com> Cc: Chris Li <chrisl@kernel.org> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Pratyush Yadav
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20571b1870 |
kho: move sanity checks to kho_restore_page()
While KHO exposes folio as the primitive externally, internally its
restoration machinery operates on pages. This can be seen with
kho_restore_folio() for example. It performs some sanity checks and hands
it over to kho_restore_page() to do the heavy lifting of page restoration.
After the work done by kho_restore_page(), kho_restore_folio() only
converts the head page to folio and returns it. Similarly,
deserialize_bitmap() operates on the head page directly to store the
order.
Move the sanity checks for valid phys and order from the public-facing
kho_restore_folio() to the private-facing kho_restore_page(). This makes
the boundary between page and folio clearer from KHO's perspective.
While at it, drop the comment above kho_restore_page(). The comment is
misleading now. The function stopped looking like free_reserved_page()
since
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Evangelos Petrongonas
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d6d5116391 |
kexec: introduce is_kho_boot()
Patch series "efi: Fix EFI boot with kexec handover (KHO)", v3. This patch series fixes a kernel panic that occurs when booting with both EFI and KHO (Kexec HandOver) enabled. The issue arises because EFI's `reserve_regions()` clears all memory regions with `memblock_remove(0, PHYS_ADDR_MAX)` before rebuilding them from EFI data. This destroys KHO scratch regions that were set up early during device tree scanning, causing a panic as the kernel has no valid memory regions for early allocations. The first patch introduces `is_kho_boot()` to allow early boot components to reliably detect if the kernel was booted via KHO-enabled kexec. The existing `kho_is_enabled()` only checks the command line and doesn't verify if an actual KHO FDT was passed. The second patch modifies EFI's `reserve_regions()` to selectively remove only non-KHO memory regions when KHO is active, preserving the critical scratch regions while still allowing EFI to rebuild its memory map. This patch (of 3): During early initialisation, after a kexec, other components, like EFI need to know if a KHO enabled kexec is performed. The `kho_is_enabled` function is not enough as in the early stages, it only reflects whether the cmdline has KHO enabled, not if an actual KHO FDT exists. Extend the KHO API with `is_kho_boot()` to provide a way for components to check if a KHO enabled kexec is performed. Link: https://lkml.kernel.org/r/cover.1755721529.git.epetron@amazon.de Link: https://lkml.kernel.org/r/7dc6674a76bf6e68cca0222ccff32427699cc02e.1755721529.git.epetron@amazon.de Signed-off-by: Evangelos Petrongonas <epetron@amazon.de> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Pratyush Yadav <pratyush@kernel.org> Cc: Alexander Graf <graf@amazon.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Changyuan Lyu <changyuanl@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Pratyush Yadav
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e76e09bdf9 |
kho: make sure kho_scratch argument is fully consumed
When specifying fixed sized scratch areas, the parser only parses the
three scratch sizes and ignores the rest of the argument. This means the
argument can have any bogus trailing characters.
For example, "kho_scratch=256M,512M,512Mfoobar" results in successful
parsing:
[ 0.000000] KHO: scratch areas: lowmem: 256MiB global: 512MiB pernode: 512MiB
It is generally a good idea to parse arguments as strictly as possible.
In addition, if bogus trailing characters are allowed in the kho_scratch
argument, it is possible that some people might end up using them and
later extensions to the argument format will cause unexpected breakages.
Make sure the argument is fully consumed after all three scratch sizes are
parsed. With this change, the bogus argument
"kho_scratch=256M,512M,512Mfoobar" results in:
[ 0.000000] Malformed early option 'kho_scratch'
Link: https://lkml.kernel.org/r/20250826123817.64681-1-pratyush@kernel.org
Signed-off-by: Pratyush Yadav <pratyush@kernel.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Alexander Graf <graf@amazon.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Changyuan Lyu <changyuanl@google.com>
Cc: Pratyush Yadav <pratyush@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Mike Rapoport (Microsoft)
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be564840bb |
kho: allow scratch areas with zero size
Patch series "kho: fixes and cleanups", v3. These are small KHO and KHO test fixes and cleanups. This patch (of 3): Parsing of kho_scratch parameter treats zero size as an invalid value, although it should be fine for user to request zero sized scratch area for some types if scratch memory, when for example there is no need to create scratch area in the low memory. Treat zero as a valid value for a scratch area size but reject kho_scratch parameter that defines no scratch memory at all. Link: https://lkml.kernel.org/r/20250811082510.4154080-1-rppt@kernel.org Link: https://lkml.kernel.org/r/20250811082510.4154080-2-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Pratyush Yadav <pratyush@kernel.org> Cc: Alexander Graf <graf@amazon.com> Cc: Baoquan He <bhe@redhat.com> Cc: Changyuan Lyu <changyuanl@google.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Thomas Weißschuh <linux@weissschuh.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Pasha Tatashin
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44958f2025 |
kho: warn if KHO is disabled due to an error
During boot scratch area is allocated based on command line parameters or auto calculated. However, scratch area may fail to allocate, and in that case KHO is disabled. Currently, no warning is printed that KHO is disabled, which makes it confusing for the end user to figure out why KHO is not available. Add the missing warning message. Link: https://lkml.kernel.org/r/20250808201804.772010-4-pasha.tatashin@soleen.com Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Pratyush Yadav <pratyush@kernel.org> Cc: Alexander Graf <graf@amazon.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baoquan He <bhe@redhat.com> Cc: Changyuan Lyu <changyuanl@google.com> Cc: Coiby Xu <coxu@redhat.com> Cc: Dave Vasilevsky <dave@vasilevsky.ca> Cc: Eric Biggers <ebiggers@google.com> Cc: Kees Cook <kees@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Pasha Tatashin
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63b17b653d |
kho: init new_physxa->phys_bits to fix lockdep
Patch series "Several KHO Hotfixes".
Three unrelated fixes for Kexec Handover.
This patch (of 3):
Lockdep shows the following warning:
INFO: trying to register non-static key. The code is fine but needs
lockdep annotation, or maybe you didn't initialize this object before use?
turning off the locking correctness validator.
[<ffffffff810133a6>] dump_stack_lvl+0x66/0xa0
[<ffffffff8136012c>] assign_lock_key+0x10c/0x120
[<ffffffff81358bb4>] register_lock_class+0xf4/0x2f0
[<ffffffff813597ff>] __lock_acquire+0x7f/0x2c40
[<ffffffff81360cb0>] ? __pfx_hlock_conflict+0x10/0x10
[<ffffffff811707be>] ? native_flush_tlb_global+0x8e/0xa0
[<ffffffff8117096e>] ? __flush_tlb_all+0x4e/0xa0
[<ffffffff81172fc2>] ? __kernel_map_pages+0x112/0x140
[<ffffffff813ec327>] ? xa_load_or_alloc+0x67/0xe0
[<ffffffff81359556>] lock_acquire+0xe6/0x280
[<ffffffff813ec327>] ? xa_load_or_alloc+0x67/0xe0
[<ffffffff8100b9e0>] _raw_spin_lock+0x30/0x40
[<ffffffff813ec327>] ? xa_load_or_alloc+0x67/0xe0
[<ffffffff813ec327>] xa_load_or_alloc+0x67/0xe0
[<ffffffff813eb4c0>] kho_preserve_folio+0x90/0x100
[<ffffffff813ebb7f>] __kho_finalize+0xcf/0x400
[<ffffffff813ebef4>] kho_finalize+0x34/0x70
This is becase xa has its own lock, that is not initialized in
xa_load_or_alloc.
Modifiy __kho_preserve_order(), to properly call
xa_init(&new_physxa->phys_bits);
Link: https://lkml.kernel.org/r/20250808201804.772010-2-pasha.tatashin@soleen.com
Fixes:
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Linus Torvalds
|
beace86e61 |
Summary of significant series in this pull request:
- The 4 patch series "mm: ksm: prevent KSM from breaking merging of new
VMAs" from Lorenzo Stoakes addresses an issue with KSM's
PR_SET_MEMORY_MERGE mode: newly mapped VMAs were not eligible for
merging with existing adjacent VMAs.
- The 4 patch series "mm/damon: introduce DAMON_STAT for simple and
practical access monitoring" from SeongJae Park adds a new kernel module
which simplifies the setup and usage of DAMON in production
environments.
- The 6 patch series "stop passing a writeback_control to swap/shmem
writeout" from Christoph Hellwig is a cleanup to the writeback code
which removes a couple of pointers from struct writeback_control.
- The 7 patch series "drivers/base/node.c: optimization and cleanups"
from Donet Tom contains largely uncorrelated cleanups to the NUMA node
setup and management code.
- The 4 patch series "mm: userfaultfd: assorted fixes and cleanups" from
Tal Zussman does some maintenance work on the userfaultfd code.
- The 5 patch series "Readahead tweaks for larger folios" from Ryan
Roberts implements some tuneups for pagecache readahead when it is
reading into order>0 folios.
- The 4 patch series "selftests/mm: Tweaks to the cow test" from Mark
Brown provides some cleanups and consistency improvements to the
selftests code.
- The 4 patch series "Optimize mremap() for large folios" from Dev Jain
does that. A 37% reduction in execution time was measured in a
memset+mremap+munmap microbenchmark.
- The 5 patch series "Remove zero_user()" from Matthew Wilcox expunges
zero_user() in favor of the more modern memzero_page().
- The 3 patch series "mm/huge_memory: vmf_insert_folio_*() and
vmf_insert_pfn_pud() fixes" from David Hildenbrand addresses some warts
which David noticed in the huge page code. These were not known to be
causing any issues at this time.
- The 3 patch series "mm/damon: use alloc_migrate_target() for
DAMOS_MIGRATE_{HOT,COLD" from SeongJae Park provides some cleanup and
consolidation work in DAMON.
- The 3 patch series "use vm_flags_t consistently" from Lorenzo Stoakes
uses vm_flags_t in places where we were inappropriately using other
types.
- The 3 patch series "mm/memfd: Reserve hugetlb folios before
allocation" from Vivek Kasireddy increases the reliability of large page
allocation in the memfd code.
- The 14 patch series "mm: Remove pXX_devmap page table bit and pfn_t
type" from Alistair Popple removes several now-unneeded PFN_* flags.
- The 5 patch series "mm/damon: decouple sysfs from core" from SeongJae
Park implememnts some cleanup and maintainability work in the DAMON
sysfs layer.
- The 5 patch series "madvise cleanup" from Lorenzo Stoakes does quite a
lot of cleanup/maintenance work in the madvise() code.
- The 4 patch series "madvise anon_name cleanups" from Vlastimil Babka
provides additional cleanups on top or Lorenzo's effort.
- The 11 patch series "Implement numa node notifier" from Oscar Salvador
creates a standalone notifier for NUMA node memory state changes.
Previously these were lumped under the more general memory on/offline
notifier.
- The 6 patch series "Make MIGRATE_ISOLATE a standalone bit" from Zi Yan
cleans up the pageblock isolation code and fixes a potential issue which
doesn't seem to cause any problems in practice.
- The 5 patch series "selftests/damon: add python and drgn based DAMON
sysfs functionality tests" from SeongJae Park adds additional drgn- and
python-based DAMON selftests which are more comprehensive than the
existing selftest suite.
- The 5 patch series "Misc rework on hugetlb faulting path" from Oscar
Salvador fixes a rather obscure deadlock in the hugetlb fault code and
follows that fix with a series of cleanups.
- The 3 patch series "cma: factor out allocation logic from
__cma_declare_contiguous_nid" from Mike Rapoport rationalizes and cleans
up the highmem-specific code in the CMA allocator.
- The 28 patch series "mm/migration: rework movable_ops page migration
(part 1)" from David Hildenbrand provides cleanups and
future-preparedness to the migration code.
- The 2 patch series "mm/damon: add trace events for auto-tuned
monitoring intervals and DAMOS quota" from SeongJae Park adds some
tracepoints to some DAMON auto-tuning code.
- The 6 patch series "mm/damon: fix misc bugs in DAMON modules" from
SeongJae Park does that.
- The 6 patch series "mm/damon: misc cleanups" from SeongJae Park also
does what it claims.
- The 4 patch series "mm: folio_pte_batch() improvements" from David
Hildenbrand cleans up the large folio PTE batching code.
- The 13 patch series "mm/damon/vaddr: Allow interleaving in
migrate_{hot,cold} actions" from SeongJae Park facilitates dynamic
alteration of DAMON's inter-node allocation policy.
- The 3 patch series "Remove unmap_and_put_page()" from Vishal Moola
provides a couple of page->folio conversions.
- The 4 patch series "mm: per-node proactive reclaim" from Davidlohr
Bueso implements a per-node control of proactive reclaim - beyond the
current memcg-based implementation.
- The 14 patch series "mm/damon: remove damon_callback" from SeongJae
Park replaces the damon_callback interface with a more general and
powerful damon_call()+damos_walk() interface.
- The 10 patch series "mm/mremap: permit mremap() move of multiple VMAs"
from Lorenzo Stoakes implements a number of mremap cleanups (of course)
in preparation for adding new mremap() functionality: newly permit the
remapping of multiple VMAs when the user is specifying MREMAP_FIXED. It
still excludes some specialized situations where this cannot be
performed reliably.
- The 3 patch series "drop hugetlb_free_pgd_range()" from Anthony Yznaga
switches some sparc hugetlb code over to the generic version and removes
the thus-unneeded hugetlb_free_pgd_range().
- The 4 patch series "mm/damon/sysfs: support periodic and automated
stats update" from SeongJae Park augments the present
userspace-requested update of DAMON sysfs monitoring files. Automatic
update is now provided, along with a tunable to control the update
interval.
- The 4 patch series "Some randome fixes and cleanups to swapfile" from
Kemeng Shi does what is claims.
- The 4 patch series "mm: introduce snapshot_page" from Luiz Capitulino
and David Hildenbrand provides (and uses) a means by which debug-style
functions can grab a copy of a pageframe and inspect it locklessly
without tripping over the races inherent in operating on the live
pageframe directly.
- The 6 patch series "use per-vma locks for /proc/pid/maps reads" from
Suren Baghdasaryan addresses the large contention issues which can be
triggered by reads from that procfs file. Latencies are reduced by more
than half in some situations. The series also introduces several new
selftests for the /proc/pid/maps interface.
- The 6 patch series "__folio_split() clean up" from Zi Yan cleans up
__folio_split()!
- The 7 patch series "Optimize mprotect() for large folios" from Dev
Jain provides some quite large (>3x) speedups to mprotect() when dealing
with large folios.
- The 2 patch series "selftests/mm: reuse FORCE_READ to replace "asm
volatile("" : "+r" (XXX));" and some cleanup" from wang lian does some
cleanup work in the selftests code.
- The 3 patch series "tools/testing: expand mremap testing" from Lorenzo
Stoakes extends the mremap() selftest in several ways, including adding
more checking of Lorenzo's recently added "permit mremap() move of
multiple VMAs" feature.
- The 22 patch series "selftests/damon/sysfs.py: test all parameters"
from SeongJae Park extends the DAMON sysfs interface selftest so that it
tests all possible user-requested parameters. Rather than the present
minimal subset.
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Merge tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
"As usual, many cleanups. The below blurbiage describes 42 patchsets.
21 of those are partially or fully cleanup work. "cleans up",
"cleanup", "maintainability", "rationalizes", etc.
I never knew the MM code was so dirty.
"mm: ksm: prevent KSM from breaking merging of new VMAs" (Lorenzo Stoakes)
addresses an issue with KSM's PR_SET_MEMORY_MERGE mode: newly
mapped VMAs were not eligible for merging with existing adjacent
VMAs.
"mm/damon: introduce DAMON_STAT for simple and practical access monitoring" (SeongJae Park)
adds a new kernel module which simplifies the setup and usage of
DAMON in production environments.
"stop passing a writeback_control to swap/shmem writeout" (Christoph Hellwig)
is a cleanup to the writeback code which removes a couple of
pointers from struct writeback_control.
"drivers/base/node.c: optimization and cleanups" (Donet Tom)
contains largely uncorrelated cleanups to the NUMA node setup and
management code.
"mm: userfaultfd: assorted fixes and cleanups" (Tal Zussman)
does some maintenance work on the userfaultfd code.
"Readahead tweaks for larger folios" (Ryan Roberts)
implements some tuneups for pagecache readahead when it is reading
into order>0 folios.
"selftests/mm: Tweaks to the cow test" (Mark Brown)
provides some cleanups and consistency improvements to the
selftests code.
"Optimize mremap() for large folios" (Dev Jain)
does that. A 37% reduction in execution time was measured in a
memset+mremap+munmap microbenchmark.
"Remove zero_user()" (Matthew Wilcox)
expunges zero_user() in favor of the more modern memzero_page().
"mm/huge_memory: vmf_insert_folio_*() and vmf_insert_pfn_pud() fixes" (David Hildenbrand)
addresses some warts which David noticed in the huge page code.
These were not known to be causing any issues at this time.
"mm/damon: use alloc_migrate_target() for DAMOS_MIGRATE_{HOT,COLD" (SeongJae Park)
provides some cleanup and consolidation work in DAMON.
"use vm_flags_t consistently" (Lorenzo Stoakes)
uses vm_flags_t in places where we were inappropriately using other
types.
"mm/memfd: Reserve hugetlb folios before allocation" (Vivek Kasireddy)
increases the reliability of large page allocation in the memfd
code.
"mm: Remove pXX_devmap page table bit and pfn_t type" (Alistair Popple)
removes several now-unneeded PFN_* flags.
"mm/damon: decouple sysfs from core" (SeongJae Park)
implememnts some cleanup and maintainability work in the DAMON
sysfs layer.
"madvise cleanup" (Lorenzo Stoakes)
does quite a lot of cleanup/maintenance work in the madvise() code.
"madvise anon_name cleanups" (Vlastimil Babka)
provides additional cleanups on top or Lorenzo's effort.
"Implement numa node notifier" (Oscar Salvador)
creates a standalone notifier for NUMA node memory state changes.
Previously these were lumped under the more general memory
on/offline notifier.
"Make MIGRATE_ISOLATE a standalone bit" (Zi Yan)
cleans up the pageblock isolation code and fixes a potential issue
which doesn't seem to cause any problems in practice.
"selftests/damon: add python and drgn based DAMON sysfs functionality tests" (SeongJae Park)
adds additional drgn- and python-based DAMON selftests which are
more comprehensive than the existing selftest suite.
"Misc rework on hugetlb faulting path" (Oscar Salvador)
fixes a rather obscure deadlock in the hugetlb fault code and
follows that fix with a series of cleanups.
"cma: factor out allocation logic from __cma_declare_contiguous_nid" (Mike Rapoport)
rationalizes and cleans up the highmem-specific code in the CMA
allocator.
"mm/migration: rework movable_ops page migration (part 1)" (David Hildenbrand)
provides cleanups and future-preparedness to the migration code.
"mm/damon: add trace events for auto-tuned monitoring intervals and DAMOS quota" (SeongJae Park)
adds some tracepoints to some DAMON auto-tuning code.
"mm/damon: fix misc bugs in DAMON modules" (SeongJae Park)
does that.
"mm/damon: misc cleanups" (SeongJae Park)
also does what it claims.
"mm: folio_pte_batch() improvements" (David Hildenbrand)
cleans up the large folio PTE batching code.
"mm/damon/vaddr: Allow interleaving in migrate_{hot,cold} actions" (SeongJae Park)
facilitates dynamic alteration of DAMON's inter-node allocation
policy.
"Remove unmap_and_put_page()" (Vishal Moola)
provides a couple of page->folio conversions.
"mm: per-node proactive reclaim" (Davidlohr Bueso)
implements a per-node control of proactive reclaim - beyond the
current memcg-based implementation.
"mm/damon: remove damon_callback" (SeongJae Park)
replaces the damon_callback interface with a more general and
powerful damon_call()+damos_walk() interface.
"mm/mremap: permit mremap() move of multiple VMAs" (Lorenzo Stoakes)
implements a number of mremap cleanups (of course) in preparation
for adding new mremap() functionality: newly permit the remapping
of multiple VMAs when the user is specifying MREMAP_FIXED. It still
excludes some specialized situations where this cannot be performed
reliably.
"drop hugetlb_free_pgd_range()" (Anthony Yznaga)
switches some sparc hugetlb code over to the generic version and
removes the thus-unneeded hugetlb_free_pgd_range().
"mm/damon/sysfs: support periodic and automated stats update" (SeongJae Park)
augments the present userspace-requested update of DAMON sysfs
monitoring files. Automatic update is now provided, along with a
tunable to control the update interval.
"Some randome fixes and cleanups to swapfile" (Kemeng Shi)
does what is claims.
"mm: introduce snapshot_page" (Luiz Capitulino and David Hildenbrand)
provides (and uses) a means by which debug-style functions can grab
a copy of a pageframe and inspect it locklessly without tripping
over the races inherent in operating on the live pageframe
directly.
"use per-vma locks for /proc/pid/maps reads" (Suren Baghdasaryan)
addresses the large contention issues which can be triggered by
reads from that procfs file. Latencies are reduced by more than
half in some situations. The series also introduces several new
selftests for the /proc/pid/maps interface.
"__folio_split() clean up" (Zi Yan)
cleans up __folio_split()!
"Optimize mprotect() for large folios" (Dev Jain)
provides some quite large (>3x) speedups to mprotect() when dealing
with large folios.
"selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));" and some cleanup" (wang lian)
does some cleanup work in the selftests code.
"tools/testing: expand mremap testing" (Lorenzo Stoakes)
extends the mremap() selftest in several ways, including adding
more checking of Lorenzo's recently added "permit mremap() move of
multiple VMAs" feature.
"selftests/damon/sysfs.py: test all parameters" (SeongJae Park)
extends the DAMON sysfs interface selftest so that it tests all
possible user-requested parameters. Rather than the present minimal
subset"
* tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (370 commits)
MAINTAINERS: add missing headers to mempory policy & migration section
MAINTAINERS: add missing file to cgroup section
MAINTAINERS: add MM MISC section, add missing files to MISC and CORE
MAINTAINERS: add missing zsmalloc file
MAINTAINERS: add missing files to page alloc section
MAINTAINERS: add missing shrinker files
MAINTAINERS: move memremap.[ch] to hotplug section
MAINTAINERS: add missing mm_slot.h file THP section
MAINTAINERS: add missing interval_tree.c to memory mapping section
MAINTAINERS: add missing percpu-internal.h file to per-cpu section
mm/page_alloc: remove trace_mm_alloc_contig_migrate_range_info()
selftests/damon: introduce _common.sh to host shared function
selftests/damon/sysfs.py: test runtime reduction of DAMON parameters
selftests/damon/sysfs.py: test non-default parameters runtime commit
selftests/damon/sysfs.py: generalize DAMON context commit assertion
selftests/damon/sysfs.py: generalize monitoring attributes commit assertion
selftests/damon/sysfs.py: generalize DAMOS schemes commit assertion
selftests/damon/sysfs.py: test DAMOS filters commitment
selftests/damon/sysfs.py: generalize DAMOS scheme commit assertion
selftests/damon/sysfs.py: test DAMOS destinations commitment
...
|
|
|
Linus Torvalds
|
8e736a2eea |
hardening updates for v6.17-rc1
- Introduce and start using TRAILING_OVERLAP() helper for fixing embedded flex array instances (Gustavo A. R. Silva) - mux: Convert mux_control_ops to a flex array member in mux_chip (Thorsten Blum) - string: Group str_has_prefix() and strstarts() (Andy Shevchenko) - Remove KCOV instrumentation from __init and __head (Ritesh Harjani, Kees Cook) - Refactor and rename stackleak feature to support Clang - Add KUnit test for seq_buf API - Fix KUnit fortify test under LTO -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRSPkdeREjth1dHnSE2KwveOeQkuwUCaIfUkgAKCRA2KwveOeQk uypLAP92r6f47sWcOw/5B9aVffX6Bypsb7dqBJQpCNxI5U1xcAEAiCrZ98UJyOeQ JQgnXd4N67K4EsS2JDc+FutRn3Yi+A8= =+5Bq -----END PGP SIGNATURE----- Merge tag 'hardening-v6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening updates from Kees Cook: - Introduce and start using TRAILING_OVERLAP() helper for fixing embedded flex array instances (Gustavo A. R. Silva) - mux: Convert mux_control_ops to a flex array member in mux_chip (Thorsten Blum) - string: Group str_has_prefix() and strstarts() (Andy Shevchenko) - Remove KCOV instrumentation from __init and __head (Ritesh Harjani, Kees Cook) - Refactor and rename stackleak feature to support Clang - Add KUnit test for seq_buf API - Fix KUnit fortify test under LTO * tag 'hardening-v6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (22 commits) sched/task_stack: Add missing const qualifier to end_of_stack() kstack_erase: Support Clang stack depth tracking kstack_erase: Add -mgeneral-regs-only to silence Clang warnings init.h: Disable sanitizer coverage for __init and __head kstack_erase: Disable kstack_erase for all of arm compressed boot code x86: Handle KCOV __init vs inline mismatches arm64: Handle KCOV __init vs inline mismatches s390: Handle KCOV __init vs inline mismatches arm: Handle KCOV __init vs inline mismatches mips: Handle KCOV __init vs inline mismatch powerpc/mm/book3s64: Move kfence and debug_pagealloc related calls to __init section configs/hardening: Enable CONFIG_INIT_ON_FREE_DEFAULT_ON configs/hardening: Enable CONFIG_KSTACK_ERASE stackleak: Split KSTACK_ERASE_CFLAGS from GCC_PLUGINS_CFLAGS stackleak: Rename stackleak_track_stack to __sanitizer_cov_stack_depth stackleak: Rename STACKLEAK to KSTACK_ERASE seq_buf: Introduce KUnit tests string: Group str_has_prefix() and strstarts() kunit/fortify: Add back "volatile" for sizeof() constants acpi: nfit: intel: avoid multiple -Wflex-array-member-not-at-end warnings ... |
|
Kees Cook
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8245d47cfa |
x86: Handle KCOV __init vs inline mismatches
GCC appears to have kind of fragile inlining heuristics, in the sense that it can change whether or not it inlines something based on optimizations. It looks like the kcov instrumentation being added (or in this case, removed) from a function changes the optimization results, and some functions marked "inline" are _not_ inlined. In that case, we end up with __init code calling a function not marked __init, and we get the build warnings I'm trying to eliminate in the coming patch that adds __no_sanitize_coverage to __init functions: WARNING: modpost: vmlinux: section mismatch in reference: xbc_exit+0x8 (section: .text.unlikely) -> _xbc_exit (section: .init.text) WARNING: modpost: vmlinux: section mismatch in reference: real_mode_size_needed+0x15 (section: .text.unlikely) -> real_mode_blob_end (section: .init.data) WARNING: modpost: vmlinux: section mismatch in reference: __set_percpu_decrypted+0x16 (section: .text.unlikely) -> early_set_memory_decrypted (section: .init.text) WARNING: modpost: vmlinux: section mismatch in reference: memblock_alloc_from+0x26 (section: .text.unlikely) -> memblock_alloc_try_nid (section: .init.text) WARNING: modpost: vmlinux: section mismatch in reference: acpi_arch_set_root_pointer+0xc (section: .text.unlikely) -> x86_init (section: .init.data) WARNING: modpost: vmlinux: section mismatch in reference: acpi_arch_get_root_pointer+0x8 (section: .text.unlikely) -> x86_init (section: .init.data) WARNING: modpost: vmlinux: section mismatch in reference: efi_config_table_is_usable+0x16 (section: .text.unlikely) -> xen_efi_config_table_is_usable (section: .init.text) This problem is somewhat fragile (though using either __always_inline or __init will deterministically solve it), but we've tripped over this before with GCC and the solution has usually been to just use __always_inline and move on. For x86 this means forcing several functions to be inline with __always_inline. Link: https://lore.kernel.org/r/20250724055029.3623499-2-kees@kernel.org Signed-off-by: Kees Cook <kees@kernel.org> |
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Zi Yan
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1bc3587a88 |
mm/page_alloc: add support for initializing pageblock as isolated
MIGRATE_ISOLATE is a standalone bit, so a pageblock cannot be initialized to just MIGRATE_ISOLATE. Add init_pageblock_migratetype() to enable initialize a pageblock with a migratetype and isolated. Link: https://lkml.kernel.org/r/20250617021115.2331563-4-ziy@nvidia.com Signed-off-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Hildenbrand <david@redhat.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kirill A. Shuemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Richard Chang <richardycc@google.com> Cc: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Pratyush Yadav
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12b9a2c05d |
kho: initialize tail pages for higher order folios properly
Currently, when restoring higher order folios, kho_restore_folio() only
calls prep_compound_page() on all the pages. That is not enough to
properly initialize the folios. The managed page count does not get
updated, the reserved flag does not get dropped, and page count does not
get initialized properly.
Restoring a higher order folio with it results in the following BUG with
CONFIG_DEBUG_VM when attempting to free the folio:
BUG: Bad page state in process test pfn:104e2b
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffffffffffffffff pfn:0x104e2b
flags: 0x2fffff80000000(node=0|zone=2|lastcpupid=0x1fffff)
raw: 002fffff80000000 0000000000000000 00000000ffffffff 0000000000000000
raw: ffffffffffffffff 0000000000000000 00000001ffffffff 0000000000000000
page dumped because: nonzero _refcount
[...]
Call Trace:
<TASK>
dump_stack_lvl+0x4b/0x70
bad_page.cold+0x97/0xb2
__free_frozen_pages+0x616/0x850
[...]
Combine the path for 0-order and higher order folios, initialize the tail
pages with a count of zero, and call adjust_managed_page_count() to
account for all the pages instead of just missing them.
In addition, since all the KHO-preserved pages get marked with
MEMBLOCK_RSRV_NOINIT by deserialize_bitmap(), the reserved flag is not
actually set (as can also be seen from the flags of the dumped page in the
logs above). So drop the ClearPageReserved() calls.
[ptyadav@amazon.de: declare i in the loop instead of at the top]
Link: https://lkml.kernel.org/r/20250613125916.39272-1-pratyush@kernel.org
Link: https://lkml.kernel.org/r/20250605171143.76963-1-pratyush@kernel.org
Fixes:
|
|
Alexander Graf
|
3bdecc3c93 |
kexec: add KHO support to kexec file loads
Kexec has 2 modes: A user space driven mode and a kernel driven mode. For the kernel driven mode, kernel code determines the physical addresses of all target buffers that the payload gets copied into. With KHO, we can only safely copy payloads into the "scratch area". Teach the kexec file loader about it, so it only allocates for that area. In addition, enlighten it with support to ask the KHO subsystem for its respective payloads to copy into target memory. Also teach the KHO subsystem how to fill the images for file loads. Link: https://lkml.kernel.org/r/20250509074635.3187114-8-changyuanl@google.com Signed-off-by: Alexander Graf <graf@amazon.com> Co-developed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Co-developed-by: Changyuan Lyu <changyuanl@google.com> Signed-off-by: Changyuan Lyu <changyuanl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Anthony Yznaga <anthony.yznaga@oracle.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ashish Kalra <ashish.kalra@amd.com> Cc: Ben Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Betkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Gowans <jgowans@amazon.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Pratyush Yadav <ptyadav@amazon.de> Cc: Rob Herring <robh@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Cc: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Lendacky <thomas.lendacky@amd.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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|
Mike Rapoport (Microsoft)
|
fc33e4b44b |
kexec: enable KHO support for memory preservation
Introduce APIs allowing KHO users to preserve memory across kexec and get access to that memory after boot of the kexeced kernel kho_preserve_folio() - record a folio to be preserved over kexec kho_restore_folio() - recreates the folio from the preserved memory kho_preserve_phys() - record physically contiguous range to be preserved over kexec. The memory preservations are tracked by two levels of xarrays to manage chunks of per-order 512 byte bitmaps. For instance if PAGE_SIZE = 4096, the entire 1G order of a 1TB x86 system would fit inside a single 512 byte bitmap. For order 0 allocations each bitmap will cover 16M of address space. Thus, for 16G of memory at most 512K of bitmap memory will be needed for order 0. At serialization time all bitmaps are recorded in a linked list of pages for the next kernel to process and the physical address of the list is recorded in KHO FDT. The next kernel then processes that list, reserves the memory ranges and later, when a user requests a folio or a physical range, KHO restores corresponding memory map entries. Link: https://lkml.kernel.org/r/20250509074635.3187114-7-changyuanl@google.com Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Co-developed-by: Changyuan Lyu <changyuanl@google.com> Signed-off-by: Changyuan Lyu <changyuanl@google.com> Cc: Alexander Graf <graf@amazon.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Anthony Yznaga <anthony.yznaga@oracle.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ashish Kalra <ashish.kalra@amd.com> Cc: Ben Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Betkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Gowans <jgowans@amazon.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Pratyush Yadav <ptyadav@amazon.de> Cc: Rob Herring <robh@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Cc: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Lendacky <thomas.lendacky@amd.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Alexander Graf
|
c609c144b0 |
kexec: add KHO parsing support
When we have a KHO kexec, we get an FDT blob and scratch region to populate the state of the system. Provide helper functions that allow architecture code to easily handle memory reservations based on them and give device drivers visibility into the KHO FDT and memory reservations so they can recover their own state. Include a fix from Arnd Bergmann <arnd@arndb.de> https://lore.kernel.org/lkml/20250424093302.3894961-1-arnd@kernel.org/. Link: https://lkml.kernel.org/r/20250509074635.3187114-6-changyuanl@google.com Signed-off-by: Alexander Graf <graf@amazon.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Co-developed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Co-developed-by: Changyuan Lyu <changyuanl@google.com> Signed-off-by: Changyuan Lyu <changyuanl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Anthony Yznaga <anthony.yznaga@oracle.com> Cc: Ashish Kalra <ashish.kalra@amd.com> Cc: Ben Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Betkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Gowans <jgowans@amazon.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Pratyush Yadav <ptyadav@amazon.de> Cc: Rob Herring <robh@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Cc: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Lendacky <thomas.lendacky@amd.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Alexander Graf
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3dc92c3114 |
kexec: add Kexec HandOver (KHO) generation helpers
Add the infrastructure to generate Kexec HandOver metadata. Kexec
HandOver is a mechanism that allows Linux to preserve state - arbitrary
properties as well as memory locations - across kexec.
It does so using 2 concepts:
1) KHO FDT - Every KHO kexec carries a KHO specific flattened device tree
blob that describes preserved memory regions. Device drivers can
register to KHO to serialize and preserve their states before kexec.
2) Scratch Regions - CMA regions that we allocate in the first kernel.
CMA gives us the guarantee that no handover pages land in those
regions, because handover pages must be at a static physical memory
location. We use these regions as the place to load future kexec
images so that they won't collide with any handover data.
Link: https://lkml.kernel.org/r/20250509074635.3187114-5-changyuanl@google.com
Signed-off-by: Alexander Graf <graf@amazon.com>
Co-developed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Co-developed-by: Pratyush Yadav <ptyadav@amazon.de>
Signed-off-by: Pratyush Yadav <ptyadav@amazon.de>
Co-developed-by: Changyuan Lyu <changyuanl@google.com>
Signed-off-by: Changyuan Lyu <changyuanl@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Anthony Yznaga <anthony.yznaga@oracle.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ashish Kalra <ashish.kalra@amd.com>
Cc: Ben Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Gowans <jgowans@amazon.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Marc Rutland <mark.rutland@arm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Thomas Lendacky <thomas.lendacky@amd.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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