Commit Graph

180 Commits

Author SHA1 Message Date
James Morse
8ddc58e0e3 arm64: errata: Remove AES hwcap for COMPAT tasks
commit 44b3834b2eed595af07021b1c64e6f9bc396398b upstream.

Cortex-A57 and Cortex-A72 have an erratum where an interrupt that
occurs between a pair of AES instructions in aarch32 mode may corrupt
the ELR. The task will subsequently produce the wrong AES result.

The AES instructions are part of the cryptographic extensions, which are
optional. User-space software will detect the support for these
instructions from the hwcaps. If the platform doesn't support these
instructions a software implementation should be used.

Remove the hwcap bits on affected parts to indicate user-space should
not use the AES instructions.

Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/r/20220714161523.279570-3-james.morse@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
[florian: resolved conflicts in arch/arm64/tools/cpucaps and cpu_errata.c]
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-29 10:12:53 +02:00
James Morse
91c4eb16e8 arm64: errata: Add Cortex-A55 to the repeat tlbi list
commit 171df58028bf4649460fb146a56a58dcb0c8f75a upstream.

Cortex-A55 is affected by an erratum where in rare circumstances the
CPUs may not handle a race between a break-before-make sequence on one
CPU, and another CPU accessing the same page. This could allow a store
to a page that has been unmapped.

Work around this by adding the affected CPUs to the list that needs
TLB sequences to be done twice.

Signed-off-by: James Morse <james.morse@arm.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220930131959.3082594-1-james.morse@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-26 12:34:24 +02:00
Ionela Voinescu
e084c6ab37 arm64: errata: add detection for AMEVCNTR01 incrementing incorrectly
commit e89d120c4b720e232cc6a94f0fcbd59c15d41489 upstream.

The AMU counter AMEVCNTR01 (constant counter) should increment at the same
rate as the system counter. On affected Cortex-A510 cores, AMEVCNTR01
increments incorrectly giving a significantly higher output value. This
results in inaccurate task scheduler utilization tracking and incorrect
feedback on CPU frequency.

Work around this problem by returning 0 when reading the affected counter
in key locations that results in disabling all users of this counter from
using it either for frequency invariance or as FFH reference counter. This
effect is the same to firmware disabling affected counters.

Details on how the two features are affected by this erratum:

 - AMU counters will not be used for frequency invariance for affected
   CPUs and CPUs in the same cpufreq policy. AMUs can still be used for
   frequency invariance for unaffected CPUs in the system. Although
   unlikely, if no alternative method can be found to support frequency
   invariance for affected CPUs (cpufreq based or solution based on
   platform counters) frequency invariance will be disabled. Please check
   the chapter on frequency invariance at
   Documentation/scheduler/sched-capacity.rst for details of its effect.

 - Given that FFH can be used to fetch either the core or constant counter
   values, restrictions are lifted regarding any of these counters
   returning a valid (!0) value. Therefore FFH is considered supported
   if there is a least one CPU that support AMUs, independent of any
   counters being disabled or affected by this erratum. Clarifying
   comments are now added to the cpc_ffh_supported(), cpu_read_constcnt()
   and cpu_read_corecnt() functions.

The above is achieved through adding a new erratum: ARM64_ERRATUM_2457168.

Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/r/20220819103050.24211-1-ionela.voinescu@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-15 11:30:08 +02:00
James Morse
285e77dbb3 arm64: errata: Add Cortex-A510 to the repeat tlbi list
commit 39fdb65f52e9a53d32a6ba719f96669fd300ae78 upstream.

Cortex-A510 is affected by an erratum where in rare circumstances the
CPUs may not handle a race between a break-before-make sequence on one
CPU, and another CPU accessing the same page. This could allow a store
to a page that has been unmapped.

Work around this by adding the affected CPUs to the list that needs
TLB sequences to be done twice.

Signed-off-by: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/r/20220704155732.21216-1-james.morse@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Lucas Wei <lucaswei@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:30:04 +02:00
Zenghui Yu
1ed630bc53 arm64: Fix match_list for erratum 1286807 on Arm Cortex-A76
commit 5e1e087457c94ad7fafbe1cf6f774c6999ee29d4 upstream.

Since commit 51f559d66527 ("arm64: Enable repeat tlbi workaround on KRYO4XX
gold CPUs"), we failed to detect erratum 1286807 on Cortex-A76 because its
entry in arm64_repeat_tlbi_list[] was accidently corrupted by this commit.

Fix this issue by creating a separate entry for Kryo4xx Gold.

Fixes: 51f559d66527 ("arm64: Enable repeat tlbi workaround on KRYO4XX gold CPUs")
Cc: Shreyas K K <quic_shrekk@quicinc.com>
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220809043848.969-1-yuzenghui@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-31 17:16:50 +02:00
Shreyas K K
149a25b82c arm64: Enable repeat tlbi workaround on KRYO4XX gold CPUs
[ Upstream commit 51f559d66527e238f9a5f82027bff499784d4eac ]

Add KRYO4XX gold/big cores to the list of CPUs that need the
repeat TLBI workaround. Apply this to the affected
KRYO4XX cores (rcpe to rfpe).

The variant and revision bits are implementation defined and are
different from the their Cortex CPU counterparts on which they are
based on, i.e., (r0p0 to r3p0) is equivalent to (rcpe to rfpe).

Signed-off-by: Shreyas K K <quic_shrekk@quicinc.com>
Reviewed-by: Sai Prakash Ranjan <quic_saipraka@quicinc.com>
Link: https://lore.kernel.org/r/20220512110134.12179-1-quic_shrekk@quicinc.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-25 09:57:36 +02:00
James Morse
4bbfd0c280 arm64: Mitigate spectre style branch history side channels
commit 558c303c9734af5a813739cd284879227f7297d2 upstream.

Speculation attacks against some high-performance processors can
make use of branch history to influence future speculation.
When taking an exception from user-space, a sequence of branches
or a firmware call overwrites or invalidates the branch history.

The sequence of branches is added to the vectors, and should appear
before the first indirect branch. For systems using KPTI the sequence
is added to the kpti trampoline where it has a free register as the exit
from the trampoline is via a 'ret'. For systems not using KPTI, the same
register tricks are used to free up a register in the vectors.

For the firmware call, arch-workaround-3 clobbers 4 registers, so
there is no choice but to save them to the EL1 stack. This only happens
for entry from EL0, so if we take an exception due to the stack access,
it will not become re-entrant.

For KVM, the existing branch-predictor-hardening vectors are used.
When a spectre version of these vectors is in use, the firmware call
is sufficient to mitigate against Spectre-BHB. For the non-spectre
versions, the sequence of branches is added to the indirect vector.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-11 12:22:35 +01:00
Rich Wiley
20109a859a arm64: kernel: disable CNP on Carmel
On NVIDIA Carmel cores, CNP behaves differently than it does on standard
ARM cores. On Carmel, if two cores have CNP enabled and share an L2 TLB
entry created by core0 for a specific ASID, a non-shareable TLBI from
core1 may still see the shared entry. On standard ARM cores, that TLBI
will invalidate the shared entry as well.

This causes issues with patchsets that attempt to do local TLBIs based
on cpumasks instead of broadcast TLBIs. Avoid these issues by disabling
CNP support for NVIDIA Carmel cores.

Signed-off-by: Rich Wiley <rwiley@nvidia.com>
Link: https://lore.kernel.org/r/20210324002809.30271-1-rwiley@nvidia.com
[will: Fix pre-existing whitespace issue]
Signed-off-by: Will Deacon <will@kernel.org>
2021-03-25 10:00:23 +00:00
Mark Rutland
6459b84697 arm64: entry: consolidate Cortex-A76 erratum 1463225 workaround
The workaround for Cortex-A76 erratum 1463225 is split across the
syscall and debug handlers in separate files. This structure currently
forces us to do some redundant work for debug exceptions from EL0, is a
little difficult to follow, and gets in the way of some future rework of
the exception entry code as it requires exceptions to be unmasked late
in the syscall handling path.

To simplify things, and as a preparatory step for future rework of
exception entry, this patch moves all the workaround logic into
entry-common.c. As the debug handler only needs to run for EL1 debug
exceptions, we no longer call it for EL0 debug exceptions, and no longer
need to check user_mode(regs) as this is always false. For clarity
cortex_a76_erratum_1463225_debug_handler() is changed to return bool.

In the SVC path, the workaround is applied earlier, but this should have
no functional impact as exceptions are still masked. In the debug path
we run the fixup before explicitly disabling preemption, but we will not
attempt to preempt before returning from the exception.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210202120341.28858-1-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-02-08 17:39:02 +00:00
Marc Zyngier
dc2286f397 Merge branch 'kvm-arm64/vector-rework' into kvmarm-master/next
Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-11-27 11:47:08 +00:00
Will Deacon
cd1f56b930 arm64: spectre: Consolidate spectre-v3a detection
The spectre-v3a mitigation is split between cpu_errata.c and spectre.c,
with the former handling detection of the problem and the latter handling
enabling of the workaround.

Move the detection logic alongside the enabling logic, like we do for the
other spectre mitigations.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Quentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20201113113847.21619-10-will@kernel.org
2020-11-16 10:43:06 +00:00
Will Deacon
c4792b6dbc arm64: spectre: Rename ARM64_HARDEN_EL2_VECTORS to ARM64_SPECTRE_V3A
Since ARM64_HARDEN_EL2_VECTORS is really a mitigation for Spectre-v3a,
rename it accordingly for consistency with the v2 and v4 mitigation.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Quentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20201113113847.21619-9-will@kernel.org
2020-11-16 10:43:06 +00:00
Will Deacon
b881cdce77 KVM: arm64: Allocate hyp vectors statically
The EL2 vectors installed when a guest is running point at one of the
following configurations for a given CPU:

  - Straight at __kvm_hyp_vector
  - A trampoline containing an SMC sequence to mitigate Spectre-v2 and
    then a direct branch to __kvm_hyp_vector
  - A dynamically-allocated trampoline which has an indirect branch to
    __kvm_hyp_vector
  - A dynamically-allocated trampoline containing an SMC sequence to
    mitigate Spectre-v2 and then an indirect branch to __kvm_hyp_vector

The indirect branches mean that VA randomization at EL2 isn't trivially
bypassable using Spectre-v3a (where the vector base is readable by the
guest).

Rather than populate these vectors dynamically, configure everything
statically and use an enumerated type to identify the vector "slot"
corresponding to one of the configurations above. This both simplifies
the code, but also makes it much easier to implement at EL2 later on.

Signed-off-by: Will Deacon <will@kernel.org>
[maz: fixed double call to kvm_init_vector_slots() on nVHE]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Quentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20201113113847.21619-8-will@kernel.org
2020-11-16 10:43:05 +00:00
Konrad Dybcio
23c2164160 arm64: cpu_errata: Apply Erratum 845719 to KRYO2XX Silver
QCOM KRYO2XX Silver cores are Cortex-A53 based and are
susceptible to the 845719 erratum. Add them to the lookup
list to apply the erratum.

Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Link: https://lore.kernel.org/r/20201104232218.198800-5-konrad.dybcio@somainline.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-11-13 09:47:08 +00:00
Rob Herring
96d389ca10 arm64: Add workaround for Arm Cortex-A77 erratum 1508412
On Cortex-A77 r0p0 and r1p0, a sequence of a non-cacheable or device load
and a store exclusive or PAR_EL1 read can cause a deadlock.

The workaround requires a DMB SY before and after a PAR_EL1 register
read. In addition, it's possible an interrupt (doing a device read) or
KVM guest exit could be taken between the DMB and PAR read, so we
also need a DMB before returning from interrupt and before returning to
a guest.

A deadlock is still possible with the workaround as KVM guests must also
have the workaround. IOW, a malicious guest can deadlock an affected
systems.

This workaround also depends on a firmware counterpart to enable the h/w
to insert DMB SY after load and store exclusive instructions. See the
errata document SDEN-1152370 v10 [1] for more information.

[1] https://static.docs.arm.com/101992/0010/Arm_Cortex_A77_MP074_Software_Developer_Errata_Notice_v10.pdf

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: kvmarm@lists.cs.columbia.edu
Link: https://lore.kernel.org/r/20201028182839.166037-2-robh@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-10-29 12:56:01 +00:00
Linus Torvalds
6734e20e39 Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
 "There's quite a lot of code here, but much of it is due to the
  addition of a new PMU driver as well as some arm64-specific selftests
  which is an area where we've traditionally been lagging a bit.

  In terms of exciting features, this includes support for the Memory
  Tagging Extension which narrowly missed 5.9, hopefully allowing
  userspace to run with use-after-free detection in production on CPUs
  that support it. Work is ongoing to integrate the feature with KASAN
  for 5.11.

  Another change that I'm excited about (assuming they get the hardware
  right) is preparing the ASID allocator for sharing the CPU page-table
  with the SMMU. Those changes will also come in via Joerg with the
  IOMMU pull.

  We do stray outside of our usual directories in a few places, mostly
  due to core changes required by MTE. Although much of this has been
  Acked, there were a couple of places where we unfortunately didn't get
  any review feedback.

  Other than that, we ran into a handful of minor conflicts in -next,
  but nothing that should post any issues.

  Summary:

   - Userspace support for the Memory Tagging Extension introduced by
     Armv8.5. Kernel support (via KASAN) is likely to follow in 5.11.

   - Selftests for MTE, Pointer Authentication and FPSIMD/SVE context
     switching.

   - Fix and subsequent rewrite of our Spectre mitigations, including
     the addition of support for PR_SPEC_DISABLE_NOEXEC.

   - Support for the Armv8.3 Pointer Authentication enhancements.

   - Support for ASID pinning, which is required when sharing
     page-tables with the SMMU.

   - MM updates, including treating flush_tlb_fix_spurious_fault() as a
     no-op.

   - Perf/PMU driver updates, including addition of the ARM CMN PMU
     driver and also support to handle CPU PMU IRQs as NMIs.

   - Allow prefetchable PCI BARs to be exposed to userspace using normal
     non-cacheable mappings.

   - Implementation of ARCH_STACKWALK for unwinding.

   - Improve reporting of unexpected kernel traps due to BPF JIT
     failure.

   - Improve robustness of user-visible HWCAP strings and their
     corresponding numerical constants.

   - Removal of TEXT_OFFSET.

   - Removal of some unused functions, parameters and prototypes.

   - Removal of MPIDR-based topology detection in favour of firmware
     description.

   - Cleanups to handling of SVE and FPSIMD register state in
     preparation for potential future optimisation of handling across
     syscalls.

   - Cleanups to the SDEI driver in preparation for support in KVM.

   - Miscellaneous cleanups and refactoring work"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (148 commits)
  Revert "arm64: initialize per-cpu offsets earlier"
  arm64: random: Remove no longer needed prototypes
  arm64: initialize per-cpu offsets earlier
  kselftest/arm64: Check mte tagged user address in kernel
  kselftest/arm64: Verify KSM page merge for MTE pages
  kselftest/arm64: Verify all different mmap MTE options
  kselftest/arm64: Check forked child mte memory accessibility
  kselftest/arm64: Verify mte tag inclusion via prctl
  kselftest/arm64: Add utilities and a test to validate mte memory
  perf: arm-cmn: Fix conversion specifiers for node type
  perf: arm-cmn: Fix unsigned comparison to less than zero
  arm64: dbm: Invalidate local TLB when setting TCR_EL1.HD
  arm64: mm: Make flush_tlb_fix_spurious_fault() a no-op
  arm64: Add support for PR_SPEC_DISABLE_NOEXEC prctl() option
  arm64: Pull in task_stack_page() to Spectre-v4 mitigation code
  KVM: arm64: Allow patching EL2 vectors even with KASLR is not enabled
  arm64: Get rid of arm64_ssbd_state
  KVM: arm64: Convert ARCH_WORKAROUND_2 to arm64_get_spectre_v4_state()
  KVM: arm64: Get rid of kvm_arm_have_ssbd()
  KVM: arm64: Simplify handling of ARCH_WORKAROUND_2
  ...
2020-10-12 10:00:51 -07:00
Marc Zyngier
31c84d6c9c arm64: Get rid of arm64_ssbd_state
Out with the old ghost, in with the new...

Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-29 16:08:17 +01:00
Marc Zyngier
29e8910a56 KVM: arm64: Simplify handling of ARCH_WORKAROUND_2
Owing to the fact that the host kernel is always mitigated, we can
drastically simplify the WA2 handling by keeping the mitigation
state ON when entering the guest. This means the guest is either
unaffected or not mitigated.

This results in a nice simplification of the mitigation space,
and the removal of a lot of code that was never really used anyway.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-29 16:08:16 +01:00
Will Deacon
c28762070c arm64: Rewrite Spectre-v4 mitigation code
Rewrite the Spectre-v4 mitigation handling code to follow the same
approach as that taken by Spectre-v2.

For now, report to KVM that the system is vulnerable (by forcing
'ssbd_state' to ARM64_SSBD_UNKNOWN), as this will be cleared up in
subsequent steps.

Signed-off-by: Will Deacon <will@kernel.org>
2020-09-29 16:08:16 +01:00
Will Deacon
9b0955baa4 arm64: Rename ARM64_SSBD to ARM64_SPECTRE_V4
In a similar manner to the renaming of ARM64_HARDEN_BRANCH_PREDICTOR
to ARM64_SPECTRE_V2, rename ARM64_SSBD to ARM64_SPECTRE_V4. This isn't
_entirely_ accurate, as we also need to take into account the interaction
with SSBS, but that will be taken care of in subsequent patches.

Signed-off-by: Will Deacon <will@kernel.org>
2020-09-29 16:08:16 +01:00
Will Deacon
d4647f0a2a arm64: Rewrite Spectre-v2 mitigation code
The Spectre-v2 mitigation code is pretty unwieldy and hard to maintain.
This is largely due to it being written hastily, without much clue as to
how things would pan out, and also because it ends up mixing policy and
state in such a way that it is very difficult to figure out what's going
on.

Rewrite the Spectre-v2 mitigation so that it clearly separates state from
policy and follows a more structured approach to handling the mitigation.

Signed-off-by: Will Deacon <will@kernel.org>
2020-09-29 16:08:15 +01:00
Will Deacon
455697adef arm64: Introduce separate file for spectre mitigations and reporting
The spectre mitigation code is spread over a few different files, which
makes it both hard to follow, but also hard to remove it should we want
to do that in future.

Introduce a new file for housing the spectre mitigations, and populate
it with the spectre-v1 reporting code to start with.

Signed-off-by: Will Deacon <will@kernel.org>
2020-09-29 16:08:15 +01:00
Will Deacon
688f1e4b6d arm64: Rename ARM64_HARDEN_BRANCH_PREDICTOR to ARM64_SPECTRE_V2
For better or worse, the world knows about "Spectre" and not about
"Branch predictor hardening". Rename ARM64_HARDEN_BRANCH_PREDICTOR to
ARM64_SPECTRE_V2 as part of moving all of the Spectre mitigations into
their own little corner.

Signed-off-by: Will Deacon <will@kernel.org>
2020-09-29 16:08:15 +01:00
Will Deacon
b181048f41 KVM: arm64: Simplify install_bp_hardening_cb()
Use is_hyp_mode_available() to detect whether or not we need to patch
the KVM vectors for branch hardening, which avoids the need to take the
vector pointers as parameters.

Signed-off-by: Will Deacon <will@kernel.org>
2020-09-29 16:08:15 +01:00
Will Deacon
5359a87d5b KVM: arm64: Replace CONFIG_KVM_INDIRECT_VECTORS with CONFIG_RANDOMIZE_BASE
The removal of CONFIG_HARDEN_BRANCH_PREDICTOR means that
CONFIG_KVM_INDIRECT_VECTORS is synonymous with CONFIG_RANDOMIZE_BASE,
so replace it.

Signed-off-by: Will Deacon <will@kernel.org>
2020-09-29 16:08:15 +01:00
Will Deacon
6e5f092784 arm64: Remove Spectre-related CONFIG_* options
The spectre mitigations are too configurable for their own good, leading
to confusing logic trying to figure out when we should mitigate and when
we shouldn't. Although the plethora of command-line options need to stick
around for backwards compatibility, the default-on CONFIG options that
depend on EXPERT can be dropped, as the mitigations only do anything if
the system is vulnerable, a mitigation is available and the command-line
hasn't disabled it.

Remove CONFIG_HARDEN_BRANCH_PREDICTOR and CONFIG_ARM64_SSBD in favour of
enabling this code unconditionally.

Signed-off-by: Will Deacon <will@kernel.org>
2020-09-29 16:08:15 +01:00
Marc Zyngier
39533e1206 arm64: Run ARCH_WORKAROUND_2 enabling code on all CPUs
Commit 606f8e7b27 ("arm64: capabilities: Use linear array for
detection and verification") changed the way we deal with per-CPU errata
by only calling the .matches() callback until one CPU is found to be
affected. At this point, .matches() stop being called, and .cpu_enable()
will be called on all CPUs.

This breaks the ARCH_WORKAROUND_2 handling, as only a single CPU will be
mitigated.

In order to address this, forcefully call the .matches() callback from a
.cpu_enable() callback, which brings us back to the original behaviour.

Fixes: 606f8e7b27 ("arm64: capabilities: Use linear array for detection and verification")
Cc: <stable@vger.kernel.org>
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>
2020-09-29 16:08:03 +01:00
Marc Zyngier
18fce56134 arm64: Run ARCH_WORKAROUND_1 enabling code on all CPUs
Commit 73f3816609 ("arm64: Advertise mitigation of Spectre-v2, or lack
thereof") changed the way we deal with ARCH_WORKAROUND_1, by moving most
of the enabling code to the .matches() callback.

This has the unfortunate effect that the workaround gets only enabled on
the first affected CPU, and no other.

In order to address this, forcefully call the .matches() callback from a
.cpu_enable() callback, which brings us back to the original behaviour.

Fixes: 73f3816609 ("arm64: Advertise mitigation of Spectre-v2, or lack thereof")
Cc: <stable@vger.kernel.org>
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>
2020-09-21 18:31:09 +01:00
Marc Zyngier
b11483ef5a arm64: Make use of ARCH_WORKAROUND_1 even when KVM is not enabled
We seem to be pretending that we don't have any firmware mitigation
when KVM is not compiled in, which is not quite expected.

Bring back the mitigation in this case.

Fixes: 4db61fef16 ("arm64: kvm: Modernize __smccc_workaround_1_smc_start annotations")
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-21 18:31:09 +01:00
Marc Zyngier
ed888cb0d1 arm64: Allow CPUs unffected by ARM erratum 1418040 to come in late
Now that we allow CPUs affected by erratum 1418040 to come in late,
this prevents their unaffected sibblings from coming in late (or
coming back after a suspend or hotplug-off, which amounts to the
same thing).

To allow this, we need to add ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU,
which amounts to set .type to ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE.

Fixes: bf87bb0881 ("arm64: Allow booting of late CPUs affected by erratum 1418040")
Reported-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200911181611.2073183-1-maz@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-09-13 13:18:10 +01:00
Marc Zyngier
bf87bb0881 arm64: Allow booting of late CPUs affected by erratum 1418040
As we can now switch from a system that isn't affected by 1418040
to a system that globally is affected, let's allow affected CPUs
to come in at a later time.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200731173824.107480-3-maz@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-08-21 11:39:56 +01:00
Paolo Bonzini
0378daef0c Merge tag 'kvmarm-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-next-5.6
KVM/arm64 updates for Linux 5.9:

- Split the VHE and nVHE hypervisor code bases, build the EL2 code
  separately, allowing for the VHE code to now be built with instrumentation

- Level-based TLB invalidation support

- Restructure of the vcpu register storage to accomodate the NV code

- Pointer Authentication available for guests on nVHE hosts

- Simplification of the system register table parsing

- MMU cleanups and fixes

- A number of post-32bit cleanups and other fixes
2020-08-09 12:58:23 -04:00
Marc Zyngier
a394cf6e85 Merge branch 'kvm-arm64/misc-5.9' into kvmarm-master/next-WIP
Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-07-28 16:26:16 +01:00
David Brazdil
a59a2edbbb KVM: arm64: Substitute RANDOMIZE_BASE for HARDEN_EL2_VECTORS
The HARDEN_EL2_VECTORS config maps vectors at a fixed location on cores which
are susceptible to Spector variant 3a (A57, A72) to prevent defeating hyp
layout randomization by leaking the value of VBAR_EL2.

Since this feature is only applicable when EL2 layout randomization is enabled,
unify both behind the same RANDOMIZE_BASE Kconfig. Majority of code remains
conditional on a capability selected for the affected cores.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200721094445.82184-3-dbrazdil@google.com
2020-07-28 10:41:11 +01:00
Florian Fainelli
09c717c92b arm64: Add missing sentinel to erratum_1463225
When the erratum_1463225 array was introduced a sentinel at the end was
missing thus causing a KASAN: global-out-of-bounds in
is_affected_midr_range_list on arm64 error.

Fixes: a9e821b89d ("arm64: Add KRYO4XX gold CPU cores to erratum list 1463225 and 1418040")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Link: https://lore.kernel.org/linux-arm-kernel/CA+G9fYs3EavpU89-rTQfqQ9GgxAMgMAk7jiiVrfP0yxj5s+Q6g@mail.gmail.com/
Link: https://lore.kernel.org/r/20200709051345.14544-1-f.fainelli@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-09 09:42:24 +01:00
Sai Prakash Ranjan
9b23d95c53 arm64: Add KRYO4XX silver CPU cores to erratum list 1530923 and 1024718
KRYO4XX silver/LITTLE CPU cores with revision r1p0 are affected by
erratum 1530923 and 1024718, so add them to the respective list.
The variant and revision bits are implementation defined and are
different from the their Cortex CPU counterparts on which they are
based on, i.e., r1p0 is equivalent to rdpe.

Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Link: https://lore.kernel.org/r/7013e8a3f857ca7e82863cc9e34a614293d7f80c.1593539394.git.saiprakash.ranjan@codeaurora.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-03 16:39:16 +01:00
Sai Prakash Ranjan
a9e821b89d arm64: Add KRYO4XX gold CPU cores to erratum list 1463225 and 1418040
KRYO4XX gold/big CPU core revisions r0p0 to r3p1 are affected by
erratum 1463225 and 1418040, so add them to the respective list.
The variant and revision bits are implementation defined and are
different from the their Cortex CPU counterparts on which they are
based on, i.e., (r0p0 to r3p1) is equivalent to (rcpe to rfpf).

Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Link: https://lore.kernel.org/r/83780e80c6377c12ca51b5d53186b61241685e49.1593539394.git.saiprakash.ranjan@codeaurora.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-03 16:39:16 +01:00
Sai Prakash Ranjan
108447fd0d arm64: Add KRYO{3,4}XX silver CPU cores to SSB safelist
QCOM KRYO{3,4}XX silver/LITTLE CPU cores are based on
Cortex-A55 and are SSB safe, hence add them to SSB
safelist -> arm64_ssb_cpus[].

Reported-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200625103123.7240-1-saiprakash.ranjan@codeaurora.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-06-25 20:18:57 +01:00
Linus Torvalds
039aeb9deb 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
c350717ec7 Merge branch 'for-next/kvm/errata' into for-next/core
KVM CPU errata rework
(Andrew Scull and Marc Zyngier)
* for-next/kvm/errata:
  KVM: arm64: Move __load_guest_stage2 to kvm_mmu.h
  arm64: Unify WORKAROUND_SPECULATIVE_AT_{NVHE,VHE}
2020-05-28 18:02:51 +01:00
Will Deacon
d82755b2e7 KVM: arm64: Kill off CONFIG_KVM_ARM_HOST
CONFIG_KVM_ARM_HOST is just a proxy for CONFIG_KVM, so remove it in favour
of the latter.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200505154520.194120-2-tabba@google.com
2020-05-16 15:04:18 +01:00
Geert Uytterhoeven
357dd8a2af arm64: cpufeature: Add "or" to mitigations for multiple errata
Several actions are not mitigations for a single erratum, but for
multiple errata.  However, printing a line like

    CPU features: detected: ARM errata 1165522, 1530923

may give the false impression that all three listed errata have been
detected.  This can confuse the user, who may think his Cortex-A55 is
suddenly affected by a Cortex-A76 erratum.

Add "or" to all descriptions for mitigations for multiple errata, to
make it clear that only one or more of the errata printed are
applicable, and not necessarily all of them.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200512145255.5520-1-geert+renesas@glider.be
Signed-off-by: Will Deacon <will@kernel.org>
2020-05-12 18:37:13 +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
Nathan Chancellor
9a25136a61 arm64: Mark call_smc_arch_workaround_1 as __maybe_unused
When building allnoconfig:

arch/arm64/kernel/cpu_errata.c:174:13: warning: unused function
'call_smc_arch_workaround_1' [-Wunused-function]
static void call_smc_arch_workaround_1(void)
            ^
1 warning generated.

Follow arch/arm and mark this function as __maybe_unused.

Fixes: 4db61fef16 ("arm64: kvm: Modernize __smccc_workaround_1_smc_start annotations")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-11 12:01:59 +00:00
Mark Brown
4db61fef16 arm64: kvm: Modernize __smccc_workaround_1_smc_start annotations
In an effort to clarify and simplify the annotation of assembly functions
in the kernel new macros have been introduced. These replace ENTRY and
ENDPROC with separate annotations for standard C callable functions,
data and code with different calling conventions.

Using these for __smccc_workaround_1_smc is more involved than for most
symbols as this symbol is annotated quite unusually, rather than just have
the explicit symbol we define _start and _end symbols which we then use to
compute the length. This does not play at all nicely with the new style
macros. Instead define a constant for the size of the function and use that
in both the C code and for .org based size checks in the assembly code.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
2020-03-09 17:35:43 +00:00
Mark Brown
6e52aab901 arm64: kvm: Modernize annotation for __bp_harden_hyp_vecs
We have recently introduced new macros for annotating assembly symbols
for things that aren't C functions, SYM_CODE_START() and SYM_CODE_END(),
in an effort to clarify and simplify our annotations of assembly files.

Using these for __bp_harden_hyp_vecs is more involved than for most symbols
as this symbol is annotated quite unusually as rather than just have the
explicit symbol we define _start and _end symbols which we then use to
compute the length. This does not play at all nicely with the new style
macros. Since the size of the vectors is a known constant which won't vary
the simplest thing to do is simply to drop the separate _start and _end
symbols and just use a #define for the size.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
2020-03-09 17:35:35 +00:00
Will Deacon
ab3906c531 Merge branch 'for-next/errata' into for-next/core
* for-next/errata: (3 commits)
  arm64: Workaround for Cortex-A55 erratum 1530923
  ...
2020-01-22 11:35:05 +00:00
Sai Prakash Ranjan
83b0c36b8a arm64: Add KRYO{3,4}XX CPU cores to spectre-v2 safe list
The "silver" KRYO3XX and KRYO4XX CPU cores are not affected by Spectre
variant 2. Add them to spectre_v2 safe list to correct the spurious
ARM_SMCCC_ARCH_WORKAROUND_1 warning and vulnerability status reported
under sysfs.

Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Tested-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
[will: tweaked commit message to remove stale mention of "gold" cores]
Signed-off-by: Will Deacon <will@kernel.org>
2020-01-17 12:46:41 +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
db0d46a58d arm64: Rename WORKAROUND_1319367 to SPECULATIVE_AT_NVHE
To match SPECULATIVE_AT_VHE let's also have a generic name for the NVHE
variant.

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 10:44:11 +00:00