diff options
| author | Anshuman Khandual <anshuman.khandual@arm.com> | 2022-11-16 19:39:15 +0530 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2022-11-18 16:52:40 +0000 |
| commit | 44ecda71fd8a70185c270f5914ac563827fe1d4c (patch) | |
| tree | b9ff785dcba56c234b9a80aab7eb1bffb6fc63e4 /Documentation/arm64/silicon-errata.rst | |
| parent | 07e39e60bbf0ccd5f895568e1afca032193705c0 (diff) | |
| download | lwn-44ecda71fd8a70185c270f5914ac563827fe1d4c.tar.gz lwn-44ecda71fd8a70185c270f5914ac563827fe1d4c.zip | |
arm64: errata: Workaround possible Cortex-A715 [ESR|FAR]_ELx corruption
If a Cortex-A715 cpu sees a page mapping permissions change from executable
to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers, on the
next instruction abort caused by permission fault.
Only user-space does executable to non-executable permission transition via
mprotect() system call which calls ptep_modify_prot_start() and ptep_modify
_prot_commit() helpers, while changing the page mapping. The platform code
can override these helpers via __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION.
Work around the problem via doing a break-before-make TLB invalidation, for
all executable user space mappings, that go through mprotect() system call.
This overrides ptep_modify_prot_start() and ptep_modify_prot_commit(), via
defining HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION on the platform thus giving
an opportunity to intercept user space exec mappings, and do the necessary
TLB invalidation. Similar interceptions are also implemented for HugeTLB.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20221116140915.356601-3-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'Documentation/arm64/silicon-errata.rst')
| -rw-r--r-- | Documentation/arm64/silicon-errata.rst | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst index 808ade4cc008..ec5f889d7681 100644 --- a/Documentation/arm64/silicon-errata.rst +++ b/Documentation/arm64/silicon-errata.rst @@ -120,6 +120,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A710 | #2224489 | ARM64_ERRATUM_2224489 | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-A715 | #2645198 | ARM64_ERRATUM_2645198 | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-X2 | #2119858 | ARM64_ERRATUM_2119858 | +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-X2 | #2224489 | ARM64_ERRATUM_2224489 | |