Commit Graph

74 Commits

Author SHA1 Message Date
Marc Zyngier 146a050f2d KVM: arm64: nv: Nested GICv3 emulation
When entering a nested VM, we set up the hypervisor control interface
based on what the guest hypervisor has set. Especially, we investigate
each list register written by the guest hypervisor whether HW bit is
set.  If so, we translate hw irq number from the guest's point of view
to the real hardware irq number if there is a mapping.

Co-developed-by: Jintack Lim <jintack@cs.columbia.edu>
Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
[Christoffer: Redesigned execution flow around vcpu load/put]
Co-developed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
[maz: Rewritten to support GICv3 instead of GICv2, NV2 support]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20250225172930.1850838-9-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-03-03 14:57:04 -08:00
Pierre-Clément Tosi ea9d7c83d1 KVM: arm64: Fix __pkvm_init_switch_pgd call ABI
Fix the mismatch between the (incorrect) C signature, C call site, and
asm implementation by aligning all three on an API passing the
parameters (pgd and SP) separately, instead of as a bundled struct.

Remove the now unnecessary memory accesses while the MMU is off from the
asm, which simplifies the C caller (as it does not need to convert a VA
struct pointer to PA) and makes the code slightly more robust by
offsetting the struct fields from C and properly expressing the call to
the C compiler (e.g. type checker and kCFI).

Fixes: f320bc742b ("KVM: arm64: Prepare the creation of s1 mappings at EL2")
Signed-off-by: Pierre-Clément Tosi <ptosi@google.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20240610063244.2828978-3-ptosi@google.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-06-20 17:40:53 +00:00
Fuad Tabba 66d5b53e20 KVM: arm64: Allocate memory mapped at hyp for host sve state in pKVM
Protected mode needs to maintain (save/restore) the host's sve
state, rather than relying on the host kernel to do that. This is
to avoid leaking information to the host about guests and the
type of operations they are performing.

As a first step towards that, allocate memory mapped at hyp, per
cpu, for the host sve state. The following patch will use this
memory to save/restore the host state.

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20240603122852.3923848-6-tabba@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-06-04 15:06:33 +01:00
Fuad Tabba 45f4ea9bcf KVM: arm64: Fix prototype for __sve_save_state/__sve_restore_state
Since the prototypes for __sve_save_state/__sve_restore_state at
hyp were added, the underlying macro has acquired a third
parameter for saving/restoring ffr.

Fix the prototypes to account for the third parameter, and
restore the ffr for the guest since it is saved.

Suggested-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240603122852.3923848-3-tabba@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-06-04 15:06:32 +01:00
Fuad Tabba 87bb39ed40 KVM: arm64: Reintroduce __sve_save_state
Now that the hypervisor is handling the host sve state in
protected mode, it needs to be able to save it.

This reverts commit e66425fc9b ("KVM: arm64: Remove unused
__sve_save_state").

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20240603122852.3923848-2-tabba@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-06-04 15:06:32 +01:00
Marc Zyngier 948e1a53c2 KVM: arm64: Simplify vgic-v3 hypercalls
Consolidate the GICv3 VMCR accessor hypercalls into the APR save/restore
hypercalls so that all of the EL2 GICv3 state is covered by a single pair
of hypercalls.

Signed-off-by: Fuad Tabba <tabba@google.com>
Acked-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240423150538.2103045-17-tabba@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-05-01 16:48:14 +01:00
Bjorn Helgaas 75841d89f3 KVM: arm64: Fix typos
Fix typos, most reported by "codespell arch/arm64".  Only touches comments,
no code changes.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: James Morse <james.morse@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Zenghui Yu <yuzenghui@huawei.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: kvmarm@lists.linux.dev
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20240103231605.1801364-6-helgaas@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-24 09:13:33 +00:00
Oliver Upton 27cde4c0fe KVM: arm64: Rename helpers for VHE vCPU load/put
The names for the helpers we expose to the 'generic' KVM code are a bit
imprecise; we switch the EL0 + EL1 sysreg context and setup trap
controls that do not need to change for every guest entry/exit. Rename +
shuffle things around a bit in preparation for loading the stage-2 MMU
context on vcpu_load().

Link: https://lore.kernel.org/r/20231018233212.2888027-5-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-10-20 17:52:01 +00:00
Jean-Philippe Brucker 373beef00f KVM: arm64: nvhe: Ignore SVE hint in SMCCC function ID
When SVE is enabled, the host may set bit 16 in SMCCC function IDs, a
hint that indicates an unused SVE state. At the moment NVHE doesn't
account for this bit when inspecting the function ID, and rejects most
calls. Clear the hint bit before comparing function IDs.

About version compatibility: the host's PSCI driver initially probes the
firmware for a SMCCC version number. If the firmware implements a
protocol recent enough (1.3), subsequent SMCCC calls have the hint bit
set. Since the hint bit was reserved in earlier versions of the
protocol, clearing it is fine regardless of the version in use.

When a new hint is added to the protocol in the future, it will be added
to ARM_SMCCC_CALL_HINTS and NVHE will handle it straight away. This
patch only clears known hints and leaves reserved bits as is, because
future SMCCC versions could use reserved bits as modifiers for the
function ID, rather than hints.

Fixes: cfa7ff959a ("arm64: smccc: Support SMCCC v1.3 SVE register saving hint")
Reported-by: Ben Horgan <ben.horgan@arm.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230911145254.934414-4-jean-philippe@linaro.org
2023-09-12 13:07:37 +01:00
Marc Zyngier 6f617d3aa6 KVM: arm64: Key use of VHE instructions in nVHE code off ARM64_KVM_HVHE
We can now start with the fun stuff: if we enable VHE *only* for
the hypervisor, we need to generate the VHE instructions when
accessing the system registers.

For this, reporpose the alternative sequence to be keyed off
ARM64_KVM_HVHE in the nVHE hypervisor code, and only there.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230609162200.2024064-10-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-06-12 23:17:23 +00:00
Marc Zyngier 57e784b407 KVM: arm64: Remove alternatives from sysreg accessors in VHE hypervisor context
In the VHE hypervisor code, we should be using the remapped VHE
accessors, no ifs, no buts. No need to generate any alternative.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230609162200.2024064-9-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-06-12 23:17:23 +00:00
Quentin Perret 8669651ce0 KVM: arm64: Provide sanitized SYS_ID_AA64SMFR0_EL1 to nVHE
We will need a sanitized copy of SYS_ID_AA64SMFR0_EL1 from the nVHE EL2
code shortly, so make sure to provide it with a copy.

Signed-off-by: Quentin Perret <qperret@google.com>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230201103755.1398086-2-qperret@google.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-02-02 21:46:43 +00:00
Will Deacon 73f38ef2ae KVM: arm64: Maintain a copy of 'kvm_arm_vmid_bits' at EL2
Sharing 'kvm_arm_vmid_bits' between EL1 and EL2 allows the host to
modify the variable arbitrarily, potentially leading to all sorts of
shenanians as this is used to configure the VTTBR register for the
guest stage-2.

In preparation for unmapping host sections entirely from EL2, maintain
a copy of 'kvm_arm_vmid_bits' in the pKVM hypervisor and initialise it
from the host value while it is still trusted.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-23-will@kernel.org
2022-11-11 17:19:35 +00:00
Will Deacon 13e248aab7 KVM: arm64: Provide I-cache invalidation by virtual address at EL2
In preparation for handling cache maintenance of guest pages from within
the pKVM hypervisor at EL2, introduce an EL2 copy of icache_inval_pou()
which will later be plumbed into the stage-2 page-table cache
maintenance callbacks, ensuring that the initial contents of pages
mapped as executable into the guest stage-2 page-table is visible to the
instruction fetcher.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-17-will@kernel.org
2022-11-11 17:16:25 +00:00
Vladimir Murzin def8c222f0 arm64: Add support of PAuth QARMA3 architected algorithm
QARMA3 is relaxed version of the QARMA5 algorithm which expected to
reduce the latency of calculation while still delivering a suitable
level of security.

Support for QARMA3 can be discovered via ID_AA64ISAR2_EL1

    APA3, bits [15:12] Indicates whether the QARMA3 algorithm is
                       implemented in the PE for address
                       authentication in AArch64 state.

    GPA3, bits [11:8]  Indicates whether the QARMA3 algorithm is
                       implemented in the PE for generic code
                       authentication in AArch64 state.

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220224124952.119612-4-vladimir.murzin@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-02-25 13:38:52 +00:00
Marc Zyngier e66425fc9b KVM: arm64: Remove unused __sve_save_state
Now that we don't have any users left for __sve_save_state, remove
it altogether. Should we ever need to save the SVE state from the
hypervisor again, we can always re-introduce it.

Suggested-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-11-22 16:01:39 +00:00
Fuad Tabba 6c30bfb18d KVM: arm64: Add handlers for protected VM System Registers
Add system register handlers for protected VMs. These cover Sys64
registers (including feature id registers), and debug.

No functional change intended as these are not hooked in yet to
the guest exit handlers introduced earlier. So when trapping is
triggered, the exit handlers let the host handle it, as before.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211010145636.1950948-8-tabba@google.com
2021-10-11 14:57:29 +01:00
Fuad Tabba 1460b4b25f KVM: arm64: Restore mdcr_el2 from vcpu
On deactivating traps, restore the value of mdcr_el2 from the
newly created and preserved host value vcpu context, rather than
directly reading the hardware register.

Up until and including this patch the two values are the same,
i.e., the hardware register and the vcpu one. A future patch will
be changing the value of mdcr_el2 on activating traps, and this
ensures that its value will be restored.

No functional change intended.

Signed-off-by: Fuad Tabba <tabba@google.com>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210817081134.2918285-7-tabba@google.com
2021-08-20 11:12:17 +01:00
Marc Zyngier 5c92a7643b Merge branch 'kvm-arm64/nvhe-panic-info' into kvmarm-master/next
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-04-13 15:38:03 +01:00
Andrew Scull f79e616f27 KVM: arm64: Use BUG and BUG_ON in nVHE hyp
hyp_panic() reports the address of the panic by using ELR_EL2, but this
isn't a useful address when hyp_panic() is called directly. Replace such
direct calls with BUG() and BUG_ON() which use BRK to trigger an
exception that then goes to hyp_panic() with the correct address. Also
remove the hyp_panic() declaration from the header file to avoid
accidental misuse.

Signed-off-by: Andrew Scull <ascull@google.com>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210318143311.839894-5-ascull@google.com
2021-04-01 09:54:37 +01:00
Marc Zyngier 7c4199375a KVM: arm64: Drop the CPU_FTR_REG_HYP_COPY infrastructure
Now that the read_ctr macro has been specialised for nVHE,
the whole CPU_FTR_REG_HYP_COPY infrastrcture looks completely
overengineered.

Simplify it by populating the two u64 quantities (MMFR0 and 1)
that the hypervisor need.

Reviewed-by: Quentin Perret <qperret@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-03-25 11:01:03 +00:00
Quentin Perret f320bc742b KVM: arm64: Prepare the creation of s1 mappings at EL2
When memory protection is enabled, the EL2 code needs the ability to
create and manage its own page-table. To do so, introduce a new set of
hypercalls to bootstrap a memory management system at EL2.

This leads to the following boot flow in nVHE Protected mode:

 1. the host allocates memory for the hypervisor very early on, using
    the memblock API;

 2. the host creates a set of stage 1 page-table for EL2, installs the
    EL2 vectors, and issues the __pkvm_init hypercall;

 3. during __pkvm_init, the hypervisor re-creates its stage 1 page-table
    and stores it in the memory pool provided by the host;

 4. the hypervisor then extends its stage 1 mappings to include a
    vmemmap in the EL2 VA space, hence allowing to use the buddy
    allocator introduced in a previous patch;

 5. the hypervisor jumps back in the idmap page, switches from the
    host-provided page-table to the new one, and wraps up its
    initialization by enabling the new allocator, before returning to
    the host.

 6. the host can free the now unused page-table created for EL2, and
    will now need to issue hypercalls to make changes to the EL2 stage 1
    mappings instead of modifying them directly.

Note that for the sake of simplifying the review, this patch focuses on
the hypervisor side of things. In other words, this only implements the
new hypercalls, but does not make use of them from the host yet. The
host-side changes will follow in a subsequent patch.

Credits to Will for __pkvm_init_switch_pgd.

Acked-by: Will Deacon <will@kernel.org>
Co-authored-by: Will Deacon <will@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210319100146.1149909-18-qperret@google.com
2021-03-19 12:01:21 +00:00
Marc Zyngier a1baa01f76 Linux 5.12-rc3
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Merge tag 'v5.12-rc3' into kvm-arm64/host-stage2

Linux 5.12-rc3

Signed-off-by: Marc Zyngier <maz@kernel.org>

# gpg: Signature made Sun 14 Mar 2021 21:41:02 GMT
# gpg:                using RSA key ABAF11C65A2970B130ABE3C479BE3E4300411886
# gpg:                issuer "torvalds@linux-foundation.org"
# gpg: Can't check signature: No public key
2021-03-19 12:01:04 +00:00
Marc Zyngier 52029198c1 KVM: arm64: Rework SVE host-save/guest-restore
In order to keep the code readable, move the host-save/guest-restore
sequences in their own functions, with the following changes:
- the hypervisor ZCR is now set from C code
- ZCR_EL2 is always used as the EL2 accessor

This results in some minor assembler macro rework.
No functional change intended.

Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-03-18 13:57:37 +00:00
Marc Zyngier 297b8603e3 KVM: arm64: Provide KVM's own save/restore SVE primitives
as we are about to change the way KVM deals with SVE, provide
KVM with its own save/restore SVE primitives.

No functional change intended.

Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-03-18 11:23:14 +00:00
Andrew Scull c4b000c392 KVM: arm64: Fix nVHE hyp panic host context restore
When panicking from the nVHE hyp and restoring the host context, x29 is
expected to hold a pointer to the host context. This wasn't being done
so fix it to make sure there's a valid pointer the host context being
used.

Rather than passing a boolean indicating whether or not the host context
should be restored, instead pass the pointer to the host context. NULL
is passed to indicate that no context should be restored.

Fixes: a2e102e20f ("KVM: arm64: nVHE: Handle hyp panics")
Cc: stable@vger.kernel.org
Signed-off-by: Andrew Scull <ascull@google.com>
[maz: partial rewrite to fit 5.12-rc1]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210219122406.1337626-1-ascull@google.com
Message-Id: <20210305185254.3730990-4-maz@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-06 04:18:40 -05:00
Suzuki K Poulose b96b0c5de6 KVM: arm64: nvhe: Save the SPE context early
The nVHE KVM hyp drains and disables the SPE buffer, before
entering the guest, as the EL1&0 translation regime
is going to be loaded with that of the guest.

But this operation is performed way too late, because :
  - The owning translation regime of the SPE buffer
    is transferred to EL2. (MDCR_EL2_E2PB == 0)
  - The guest Stage1 is loaded.

Thus the flush could use the host EL1 virtual address,
but use the EL2 translations instead of host EL1, for writing
out any cached data.

Fix this by moving the SPE buffer handling early enough.
The restore path is doing the right thing.

Fixes: 014c4c77aa ("KVM: arm64: Improve debug register save/restore flow")
Cc: stable@vger.kernel.org
Cc: Christoffer Dall <christoffer.dall@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexandru Elisei <alexandru.elisei@arm.com>
Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210302120345.3102874-1-suzuki.poulose@arm.com
Message-Id: <20210305185254.3730990-2-maz@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-06 04:18:39 -05:00
David Brazdil eeeee7193d KVM: arm64: Bootstrap PSCI SMC handler in nVHE EL2
Add a handler of PSCI SMCs in nVHE hyp code. The handler is initialized
with the version used by the host's PSCI driver and the function IDs it
was configured with. If the SMC function ID matches one of the
configured PSCI calls (for v0.1) or falls into the PSCI function ID
range (for v0.2+), the SMC is handled by the PSCI handler. For now, all
SMCs return PSCI_RET_NOT_SUPPORTED.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201202184122.26046-17-dbrazdil@google.com
2020-12-04 10:08:34 +00:00
David Brazdil 63fec24351 KVM: arm64: Move hyp-init params to a per-CPU struct
Once we start initializing KVM on newly booted cores before the rest of
the kernel, parameters to __do_hyp_init will need to be provided by EL2
rather than EL1. At that point it will not be possible to pass its three
arguments directly because PSCI_CPU_ON only supports one context
argument.

Refactor __do_hyp_init to accept its parameters in a struct. This
prepares the code for KVM booting cores as well as removes any limits on
the number of __do_hyp_init arguments.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201202184122.26046-11-dbrazdil@google.com
2020-12-04 10:08:32 +00:00
Andrew Scull a2e102e20f KVM: arm64: nVHE: Handle hyp panics
Restore the host context when panicking from hyp to give the best chance
of the panic being clean.

The host requires that registers be preserved such as x18 for the shadow
callstack. If the panic is caused by an exception from EL1, the host
context is still valid so the panic can return straight back to the
host. If the panic comes from EL2 then it's most likely that the hyp
context is active and the host context needs to be restored.

There are windows before and after the host context is saved and
restored that restoration is attempted incorrectly and the panic won't
be clean.

Signed-off-by: Andrew Scull <ascull@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200915104643.2543892-14-ascull@google.com
2020-09-15 18:39:03 +01:00
Andrew Scull b619d9aa8b KVM: arm64: Introduce hyp context
During __guest_enter, save and restore from a new hyp context rather
than the host context. This is preparation for separation of the hyp and
host context in nVHE.

Signed-off-by: Andrew Scull <ascull@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200915104643.2543892-9-ascull@google.com
2020-09-15 18:39:02 +01:00
Andrew Scull a0e479523e KVM: arm64: Save chosen hyp vector to a percpu variable
Introduce a percpu variable to hold the address of the selected hyp
vector that will be used with guests. This avoids the selection process
each time a guest is being entered and can be used by nVHE when a
separate vector is introduced for the host.

Signed-off-by: Andrew Scull <ascull@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200915104643.2543892-6-ascull@google.com
2020-09-15 18:39:02 +01:00
Andrew Scull 6a0259ed29 KVM: arm64: Remove hyp_panic arguments
hyp_panic is able to find all the context it needs from within itself so
remove the argument. The __hyp_panic wrapper becomes redundant so is
also removed.

Signed-off-by: Andrew Scull <ascull@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200915104643.2543892-3-ascull@google.com
2020-09-15 18:39:01 +01:00
David Brazdil c50cb04303 KVM: arm64: Remove __hyp_text macro, use build rules instead
With nVHE code now fully separated from the rest of the kernel, the effects of
the __hyp_text macro (which had to be applied on all nVHE code) can be
achieved with build rules instead. The macro used to:
  (a) move code to .hyp.text ELF section, now done by renaming .text using
      `objcopy`, and
  (b) `notrace` and `__noscs` would negate effects of CC_FLAGS_FTRACE and
      CC_FLAGS_SCS, respectivelly, now those flags are  erased from
      KBUILD_CFLAGS (same way as in EFI stub).

Note that by removing __hyp_text from code shared with VHE, all VHE code is now
compiled into .text and without `notrace` and `__noscs`.

Use of '.pushsection .hyp.text' removed from assembly files as this is now also
covered by the build rules.

For MAINTAINERS: if needed to re-run, uses of macro were removed with the
following command. Formatting was fixed up manually.

  find arch/arm64/kvm/hyp -type f -name '*.c' -o -name '*.h' \
       -exec sed -i 's/ __hyp_text//g' {} +

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-15-dbrazdil@google.com
2020-07-05 18:38:45 +01:00
David Brazdil 9aebdea494 KVM: arm64: Duplicate hyp/timer-sr.c for VHE/nVHE
timer-sr.c contains a HVC handler for setting CNTVOFF_EL2 and two helper
functions for controlling access to physical counter. The former is used by
both VHE/nVHE and is duplicated, the latter are used only by nVHE and moved
to nvhe/timer-sr.c.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-13-dbrazdil@google.com
2020-07-05 18:38:38 +01:00
David Brazdil 13aeb9b400 KVM: arm64: Split hyp/sysreg-sr.c to VHE/nVHE
sysreg-sr.c contains KVM's code for saving/restoring system registers, with
some code shared between VHE/nVHE. These common routines are moved to
a header file, VHE-specific code is moved to vhe/sysreg-sr.c and nVHE-specific
code to nvhe/sysreg-sr.c.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-12-dbrazdil@google.com
2020-07-05 18:38:29 +01:00
David Brazdil 09cf57eba3 KVM: arm64: Split hyp/switch.c to VHE/nVHE
switch.c implements context-switching for KVM, with large parts shared between
VHE/nVHE. These common routines are moved to a header file, VHE-specific code
is moved to vhe/switch.c and nVHE-specific code is moved to nvhe/switch.c.

Previously __kvm_vcpu_run needed a different symbol name for VHE/nVHE. This
is cleaned up and the caller in arm.c simplified.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200625131420.71444-10-dbrazdil@google.com
2020-07-05 18:38:21 +01:00
Linus Torvalds 039aeb9deb ARM:
- Move the arch-specific code into arch/arm64/kvm
 - Start the post-32bit cleanup
 - Cherry-pick a few non-invasive pre-NV patches
 
 x86:
 - Rework of TLB flushing
 - Rework of event injection, especially with respect to nested virtualization
 - Nested AMD event injection facelift, building on the rework of generic code
 and fixing a lot of corner cases
 - Nested AMD live migration support
 - Optimization for TSC deadline MSR writes and IPIs
 - Various cleanups
 - Asynchronous page fault cleanups (from tglx, common topic branch with tip tree)
 - Interrupt-based delivery of asynchronous "page ready" events (host side)
 - Hyper-V MSRs and hypercalls for guest debugging
 - VMX preemption timer fixes
 
 s390:
 - Cleanups
 
 Generic:
 - switch vCPU thread wakeup from swait to rcuwait
 
 The other architectures, and the guest side of the asynchronous page fault
 work, will come next week.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "ARM:
   - Move the arch-specific code into arch/arm64/kvm

   - Start the post-32bit cleanup

   - Cherry-pick a few non-invasive pre-NV patches

  x86:
   - Rework of TLB flushing

   - Rework of event injection, especially with respect to nested
     virtualization

   - Nested AMD event injection facelift, building on the rework of
     generic code and fixing a lot of corner cases

   - Nested AMD live migration support

   - Optimization for TSC deadline MSR writes and IPIs

   - Various cleanups

   - Asynchronous page fault cleanups (from tglx, common topic branch
     with tip tree)

   - Interrupt-based delivery of asynchronous "page ready" events (host
     side)

   - Hyper-V MSRs and hypercalls for guest debugging

   - VMX preemption timer fixes

  s390:
   - Cleanups

  Generic:
   - switch vCPU thread wakeup from swait to rcuwait

  The other architectures, and the guest side of the asynchronous page
  fault work, will come next week"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (256 commits)
  KVM: selftests: fix rdtsc() for vmx_tsc_adjust_test
  KVM: check userspace_addr for all memslots
  KVM: selftests: update hyperv_cpuid with SynDBG tests
  x86/kvm/hyper-v: Add support for synthetic debugger via hypercalls
  x86/kvm/hyper-v: enable hypercalls regardless of hypercall page
  x86/kvm/hyper-v: Add support for synthetic debugger interface
  x86/hyper-v: Add synthetic debugger definitions
  KVM: selftests: VMX preemption timer migration test
  KVM: nVMX: Fix VMX preemption timer migration
  x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exit
  KVM: x86/pmu: Support full width counting
  KVM: x86/pmu: Tweak kvm_pmu_get_msr to pass 'struct msr_data' in
  KVM: x86: announce KVM_FEATURE_ASYNC_PF_INT
  KVM: x86: acknowledgment mechanism for async pf page ready notifications
  KVM: x86: interrupt based APF 'page ready' event delivery
  KVM: introduce kvm_read_guest_offset_cached()
  KVM: rename kvm_arch_can_inject_async_page_present() to kvm_arch_can_dequeue_async_page_present()
  KVM: x86: extend struct kvm_vcpu_pv_apf_data with token info
  Revert "KVM: async_pf: Fix #DF due to inject "Page not Present" and "Page Ready" exceptions simultaneously"
  KVM: VMX: Replace zero-length array with flexible-array
  ...
2020-06-03 15:13:47 -07:00
Will Deacon 082af5ec50 Merge branch 'for-next/scs' into for-next/core
Support for Clang's Shadow Call Stack in the kernel
(Sami Tolvanen and Will Deacon)
* for-next/scs:
  arm64: entry-ftrace.S: Update comment to indicate that x18 is live
  scs: Move DEFINE_SCS macro into core code
  scs: Remove references to asm/scs.h from core code
  scs: Move scs_overflow_check() out of architecture code
  arm64: scs: Use 'scs_sp' register alias for x18
  scs: Move accounting into alloc/free functions
  arm64: scs: Store absolute SCS stack pointer value in thread_info
  efi/libstub: Disable Shadow Call Stack
  arm64: scs: Add shadow stacks for SDEI
  arm64: Implement Shadow Call Stack
  arm64: Disable SCS for hypervisor code
  arm64: vdso: Disable Shadow Call Stack
  arm64: efi: Restore register x18 if it was corrupted
  arm64: Preserve register x18 when CPU is suspended
  arm64: Reserve register x18 from general allocation with SCS
  scs: Disable when function graph tracing is enabled
  scs: Add support for stack usage debugging
  scs: Add page accounting for shadow call stack allocations
  scs: Add support for Clang's Shadow Call Stack (SCS)
2020-05-28 18:03:40 +01:00
Marc Zyngier fe677be989 KVM: arm64: Move __load_guest_stage2 to kvm_mmu.h
Having __load_guest_stage2 in kvm_hyp.h is quickly going to trigger
a circular include problem. In order to avoid this, let's move
it to kvm_mmu.h, where it will be a better fit anyway.

In the process, drop the __hyp_text annotation, which doesn't help
as the function is marked as __always_inline.

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2020-05-28 17:29:13 +01:00
Christoffer Dall fc5d1f1a42 KVM: arm64: vgic-v3: Take cpu_if pointer directly instead of vcpu
If we move the used_lrs field to the version-specific cpu interface
structure, the following functions only operate on the struct
vgic_v3_cpu_if and not the full vcpu:

  __vgic_v3_save_state
  __vgic_v3_restore_state
  __vgic_v3_activate_traps
  __vgic_v3_deactivate_traps
  __vgic_v3_save_aprs
  __vgic_v3_restore_aprs

This is going to be very useful for nested virt, so move the used_lrs
field and change the prototypes and implementations of these functions to
take the cpu_if parameter directly.

No functional change.

Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-05-28 11:57:10 +01:00
Sami Tolvanen 9654736891 arm64: Disable SCS for hypervisor code
Disable SCS for code that runs at a different exception level by
adding __noscs to __hyp_text.

Suggested-by: James Morse <james.morse@arm.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2020-05-15 16:35:50 +01:00
Andrew Scull 02ab1f5018 arm64: Unify WORKAROUND_SPECULATIVE_AT_{NVHE,VHE}
Errata 1165522, 1319367 and 1530923 each allow TLB entries to be
allocated as a result of a speculative AT instruction. In order to
avoid mandating VHE on certain affected CPUs, apply the workaround to
both the nVHE and the VHE case for all affected CPUs.

Signed-off-by: Andrew Scull <ascull@google.com>
Acked-by: Will Deacon <will@kernel.org>
CC: Marc Zyngier <maz@kernel.org>
CC: James Morse <james.morse@arm.com>
CC: Suzuki K Poulose <suzuki.poulose@arm.com>
CC: Will Deacon <will@kernel.org>
CC: Steven Price <steven.price@arm.com>
Link: https://lore.kernel.org/r/20200504094858.108917-1-ascull@google.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-05-04 16:05:47 +01:00
Paolo Bonzini e951445f4d KVM/arm fixes for 5.6, take #1
- Fix compilation on 32bit
 - Move  VHE guest entry/exit into the VHE-specific entry code
 - Make sure all functions called by the non-VHE HYP code is tagged as __always_inline
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Merge tag 'kvmarm-fixes-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm fixes for 5.6, take #1

- Fix compilation on 32bit
- Move  VHE guest entry/exit into the VHE-specific entry code
- Make sure all functions called by the non-VHE HYP code is tagged as __always_inline
2020-02-28 11:50:06 +01:00
James Morse 8c2d146ee7 KVM: arm64: Define our own swab32() to avoid a uapi static inline
KVM uses swab32() when mediating GIC MMIO accesses if the GICV is badly
aligned, and the host and guest differ in endianness.

arm64 doesn't provide a __arch_swab32(), so __fswab32() is always backed
by the macro implementation that the compiler reduces to a single
instruction. But the static-inline causes problems for KVM if the compiler
chooses not to inline this function, it may not be located in the
__hyp_text where __vgic_v2_perform_cpuif_access() needs it.

Create our own __kvm_swab32() macro that calls ___constant_swab32()
directly. This way we know it will always be inlined.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200220165839.256881-3-james.morse@arm.com
2020-02-22 11:01:47 +00:00
Steven Price 275fa0ea2c arm64: Workaround for Cortex-A55 erratum 1530923
Cortex-A55 erratum 1530923 allows TLB entries to be allocated as a
result of a speculative AT instruction. This may happen in the middle of
a guest world switch while the relevant VMSA configuration is in an
inconsistent state, leading to erroneous content being allocated into
TLBs.

The same workaround as is used for Cortex-A76 erratum 1165522
(WORKAROUND_SPECULATIVE_AT_VHE) can be used here. Note that this
mandates the use of VHE on affected parts.

Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Steven Price <steven.price@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-01-16 10:44:14 +00:00
Steven Price e85d68faed arm64: Rename WORKAROUND_1165522 to SPECULATIVE_AT_VHE
Cortex-A55 is affected by a similar erratum, so rename the existing
workaround for errarum 1165522 so it can be used for both errata.

Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-01-16 10:43:53 +00:00
Marc Zyngier 084b5a80e8 arm64: KVM: Kill hyp_alternate_select()
hyp_alternate_select() is now completely unused. Goodbye.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
2019-09-09 18:16:32 +01:00
Dave Martin fdec2a9ef8 KVM: arm64: Migrate _elx sysreg accessors to msr_s/mrs_s
Currently, the {read,write}_sysreg_el*() accessors for accessing
particular ELs' sysregs in the presence of VHE rely on some local
hacks and define their system register encodings in a way that is
inconsistent with the core definitions in <asm/sysreg.h>.

As a result, it is necessary to add duplicate definitions for any
system register that already needs a definition in sysreg.h for
other reasons.

This is a bit of a maintenance headache, and the reasons for the
_el*() accessors working the way they do is a bit historical.

This patch gets rid of the shadow sysreg definitions in
<asm/kvm_hyp.h>, converts the _el*() accessors to use the core
__msr_s/__mrs_s interface, and converts all call sites to use the
standard sysreg #define names (i.e., upper case, with SYS_ prefix).

This patch will conflict heavily anyway, so the opportunity
to clean up some bad whitespace in the context of the changes is
taken.

The change exposes a few system registers that have no sysreg.h
definition, due to msr_s/mrs_s being used in place of msr/mrs:
additions are made in order to fill in the gaps.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoffer Dall <christoffer.dall@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://www.spinics.net/lists/kvm-arm/msg31717.html
[Rebased to v4.21-rc1]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
[Rebased to v5.2-rc5, changelog updates]
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-07-05 13:57:25 +01:00
Thomas Gleixner caab277b1d treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not see http www gnu org
  licenses

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 503 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:07 +02:00