arm64: errata: Expand speculative SSBS workaround
[ Upstream commit 75b3c43eab ]
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 Cortex-X4 and Neoverse-V3, in commit:
7187bb7d0b ("arm64: errata: Add workaround for Arm errata 3194386 and 3312417")
... as per 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/
Since then, similar errata have been published for a number of other Arm Ltd
CPUs, for which the mitigation is the same. This is described in their
respective SDEN documents:
* Cortex-A710 SDEN v19.0, errataum 3324338
https://developer.arm.com/documentation/SDEN-1775101/1900/?lang=en
* Cortex-A720 SDEN v11.0, erratum 3456091
https://developer.arm.com/documentation/SDEN-2439421/1100/?lang=en
* Cortex-X2 SDEN v19.0, erratum 3324338
https://developer.arm.com/documentation/SDEN-1775100/1900/?lang=en
* Cortex-X3 SDEN v14.0, erratum 3324335
https://developer.arm.com/documentation/SDEN-2055130/1400/?lang=en
* Cortex-X925 SDEN v8.0, erratum 3324334
https://developer.arm.com/documentation/109108/800/?lang=en
* Neoverse-N2 SDEN v17.0, erratum 3324339
https://developer.arm.com/documentation/SDEN-1982442/1700/?lang=en
* Neoverse-V2 SDEN v9.0, erratum 3324336
https://developer.arm.com/documentation/SDEN-2332927/900/?lang=en
Note that due to shared design lineage, some CPUs share the same erratum
number.
Add these to the existing mitigation under CONFIG_ARM64_ERRATUM_3194386.
As listing all of the erratum IDs in the runtime description would be
unwieldy, this is reduced to:
"SSBS not fully self-synchronizing"
... matching the description of the errata in all of the SDENs.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20240603111812.1514101-6-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
[ Mark: fix conflicts and renames ]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
1f88d69ca1