diff options
| author | Mark Rutland <mark.rutland@arm.com> | 2024-05-08 09:14:00 +0100 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2024-05-10 12:21:57 +0100 |
| commit | 7187bb7d0b5c7dfa18ca82e9e5c75e13861b1d88 (patch) | |
| tree | 1e7110fc3a7d2128241b578cefc63fa210f721dc /arch/arm64/tools | |
| parent | 0ce85db6c2141b7ffb95709d76fc55a27ff3cdc1 (diff) | |
arm64: errata: Add workaround for Arm errata 3194386 and 3312417
Cortex-X4 and Neoverse-V3 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. This is described in their Software Developer Errata Notice (SDEN)
documents:
* Cortex-X4 SDEN v8.0, erratum 3194386:
https://developer.arm.com/documentation/SDEN-2432808/0800/
* Neoverse-V3 SDEN v6.0, erratum 3312417:
https://developer.arm.com/documentation/SDEN-2891958/0600/
To workaround these errata, it is necessary to place a speculation
barrier (SB) after MSR to the SSBS special-purpose register. This patch
adds the requisite SB after writes to SSBS within the kernel, and hides
the presence of SSBS from EL0 such that userspace software which cares
about SSBS will manipulate this via prctl(PR_GET_SPECULATION_CTRL, ...).
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/20240508081400.235362-5-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/tools')
| -rw-r--r-- | arch/arm64/tools/cpucaps | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/tools/cpucaps b/arch/arm64/tools/cpucaps index 62b2838a231a..ac3429d892b9 100644 --- a/arch/arm64/tools/cpucaps +++ b/arch/arm64/tools/cpucaps @@ -102,4 +102,5 @@ WORKAROUND_NVIDIA_CARMEL_CNP WORKAROUND_QCOM_FALKOR_E1003 WORKAROUND_REPEAT_TLBI WORKAROUND_SPECULATIVE_AT +WORKAROUND_SPECULATIVE_SSBS WORKAROUND_SPECULATIVE_UNPRIV_LOAD |