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author | Mark Rutland <mark.rutland@arm.com> | 2024-08-01 11:18:03 +0100 |
---|---|---|
committer | Catalin Marinas <catalin.marinas@arm.com> | 2024-08-01 16:11:28 +0100 |
commit | adeec61a4723fd3e39da68db4cc4d924e6d7f641 (patch) | |
tree | 54599756618d299775cd3b5ad0a0f33868aa41f4 /Documentation | |
parent | 9ef54a384526911095db465e77acc1cb5266b32c (diff) | |
download | lwn-adeec61a4723fd3e39da68db4cc4d924e6d7f641.tar.gz lwn-adeec61a4723fd3e39da68db4cc4d924e6d7f641.zip |
arm64: errata: Expand speculative SSBS workaround (again)
A number of Arm Ltd CPUs suffer from errata whereby an MSR to the SSBS
special-purpose register does not affect subsequent speculative
instructions, permitting speculative store bypassing for a window of
time.
We worked around this for a number of CPUs in commits:
* 7187bb7d0b5c7dfa ("arm64: errata: Add workaround for Arm errata 3194386 and 3312417")
* 75b3c43eab594bfb ("arm64: errata: Expand speculative SSBS workaround")
Since then, similar errata have been published for a number of other Arm
Ltd CPUs, for which the same mitigation is sufficient. This is described
in their respective Software Developer Errata Notice (SDEN) documents:
* Cortex-A76 (MP052) SDEN v31.0, erratum 3324349
https://developer.arm.com/documentation/SDEN-885749/3100/
* Cortex-A77 (MP074) SDEN v19.0, erratum 3324348
https://developer.arm.com/documentation/SDEN-1152370/1900/
* Cortex-A78 (MP102) SDEN v21.0, erratum 3324344
https://developer.arm.com/documentation/SDEN-1401784/2100/
* Cortex-A78C (MP138) SDEN v16.0, erratum 3324346
https://developer.arm.com/documentation/SDEN-1707916/1600/
* Cortex-A78C (MP154) SDEN v10.0, erratum 3324347
https://developer.arm.com/documentation/SDEN-2004089/1000/
* Cortex-A725 (MP190) SDEN v5.0, erratum 3456106
https://developer.arm.com/documentation/SDEN-2832921/0500/
* Cortex-X1 (MP077) SDEN v21.0, erratum 3324344
https://developer.arm.com/documentation/SDEN-1401782/2100/
* Cortex-X1C (MP136) SDEN v16.0, erratum 3324346
https://developer.arm.com/documentation/SDEN-1707914/1600/
* Neoverse-N1 (MP050) SDEN v32.0, erratum 3324349
https://developer.arm.com/documentation/SDEN-885747/3200/
* Neoverse-V1 (MP076) SDEN v19.0, erratum 3324341
https://developer.arm.com/documentation/SDEN-1401781/1900/
Note that due to the manner in which Arm develops IP and tracks errata,
some CPUs share a common erratum number and some CPUs have multiple
erratum numbers for the same HW issue.
On parts without SB, it is necessary to use ISB for the workaround. The
spec_bar() macro used in the mitigation will expand to a "DSB SY; ISB"
sequence in this case, which is sufficient on all affected parts.
Enable the existing mitigation by adding the relevant MIDRs to
erratum_spec_ssbs_list. The list is sorted alphanumerically (involving
moving Neoverse-V3 after Neoverse-V2) so that this is easy to audit and
potentially extend again in future. The Kconfig text is also updated to
clarify the set of affected parts and the mitigation.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20240801101803.1982459-4-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/arch/arm64/silicon-errata.rst | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/Documentation/arch/arm64/silicon-errata.rst b/Documentation/arch/arm64/silicon-errata.rst index bb83c5d8c675..50327c05be8d 100644 --- a/Documentation/arch/arm64/silicon-errata.rst +++ b/Documentation/arch/arm64/silicon-errata.rst @@ -122,10 +122,18 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A76 | #1490853 | N/A | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-A76 | #3324349 | ARM64_ERRATUM_3194386 | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A77 | #1491015 | N/A | +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A77 | #1508412 | ARM64_ERRATUM_1508412 | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-A77 | #3324348 | ARM64_ERRATUM_3194386 | ++----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-A78 | #3324344 | ARM64_ERRATUM_3194386 | ++----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-A78C | #3324346,3324347| ARM64_ERRATUM_3194386 | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A710 | #2119858 | ARM64_ERRATUM_2119858 | +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A710 | #2054223 | ARM64_ERRATUM_2054223 | @@ -138,8 +146,14 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A720 | #3456091 | ARM64_ERRATUM_3194386 | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-A725 | #3456106 | ARM64_ERRATUM_3194386 | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-X1 | #1502854 | N/A | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-X1 | #3324344 | ARM64_ERRATUM_3194386 | ++----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-X1C | #3324346 | ARM64_ERRATUM_3194386 | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-X2 | #2119858 | ARM64_ERRATUM_2119858 | +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-X2 | #2224489 | ARM64_ERRATUM_2224489 | @@ -160,6 +174,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-N1 | #1542419 | ARM64_ERRATUM_1542419 | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Neoverse-N1 | #3324349 | ARM64_ERRATUM_3194386 | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-N2 | #2139208 | ARM64_ERRATUM_2139208 | +----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-N2 | #2067961 | ARM64_ERRATUM_2067961 | @@ -170,6 +186,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-V1 | #1619801 | N/A | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Neoverse-V1 | #3324341 | ARM64_ERRATUM_3194386 | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-V2 | #3324336 | ARM64_ERRATUM_3194386 | +----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-V3 | #3312417 | ARM64_ERRATUM_3194386 | |