This series is a v6.11.y only backport (based on v6.11.2) of the recent MIDR updates for the speculative SSBS workaround, which were originally posted at:
https://lore.kernel.org/linux-arm-kernel/20240930111705.3352047-1-mark.rutla... https://lore.kernel.org/linux-arm-kernel/20241003225239.321774-1-eahariha@li...
... and were originally merged upstream in v6.12-rc2.
This series does not apply to earlier stable trees, which will receive a separate backport.
Mark.
Easwar Hariharan (1): arm64: Subscribe Microsoft Azure Cobalt 100 to erratum 3194386
Mark Rutland (2): arm64: cputype: Add Neoverse-N3 definitions arm64: errata: Expand speculative SSBS workaround once more
Documentation/arch/arm64/silicon-errata.rst | 6 ++++++ arch/arm64/Kconfig | 2 ++ arch/arm64/include/asm/cputype.h | 2 ++ arch/arm64/kernel/cpu_errata.c | 3 +++ 4 files changed, 13 insertions(+)
[ Upstream commit 924725707d80bc2588cefafef76ff3f164d299bc ]
Add cputype definitions for Neoverse-N3. These will be used for errata detection in subsequent patches.
These values can be found in Table A-261 ("MIDR_EL1 bit descriptions") in issue 02 of the Neoverse-N3 TRM, which can be found at:
https://developer.arm.com/documentation/107997/0000/?lang=en
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/20240930111705.3352047-2-mark.rutland@arm.com Signed-off-by: Catalin Marinas catalin.marinas@arm.com [ Mark: trivial backport ] Signed-off-by: Mark Rutland mark.rutland@arm.com --- arch/arm64/include/asm/cputype.h | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h index 5a7dfeb8e8eb5..488f8e7513495 100644 --- a/arch/arm64/include/asm/cputype.h +++ b/arch/arm64/include/asm/cputype.h @@ -94,6 +94,7 @@ #define ARM_CPU_PART_NEOVERSE_V3 0xD84 #define ARM_CPU_PART_CORTEX_X925 0xD85 #define ARM_CPU_PART_CORTEX_A725 0xD87 +#define ARM_CPU_PART_NEOVERSE_N3 0xD8E
#define APM_CPU_PART_XGENE 0x000 #define APM_CPU_VAR_POTENZA 0x00 @@ -176,6 +177,7 @@ #define MIDR_NEOVERSE_V3 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_V3) #define MIDR_CORTEX_X925 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_X925) #define MIDR_CORTEX_A725 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A725) +#define MIDR_NEOVERSE_N3 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N3) #define MIDR_THUNDERX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX) #define MIDR_THUNDERX_81XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_81XX) #define MIDR_THUNDERX_83XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_83XX)
[ Upstream commit 081eb7932c2b244f63317a982c5e3990e2c7fbdd ]
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") * 145502cac7ea70b5 ("arm64: errata: Expand speculative SSBS workaround (again)")
Since then, a (hopefully final) batch of updates have been published, with two more affected CPUs. For the affected CPUs the existing mitigation is sufficient, as described in their respective Software Developer Errata Notice (SDEN) documents:
* Cortex-A715 (MP148) SDEN v15.0, erratum 3456084 https://developer.arm.com/documentation/SDEN-2148827/1500/
* Neoverse-N3 (MP195) SDEN v5.0, erratum 3456111 https://developer.arm.com/documentation/SDEN-3050973/0500/
Enable the existing mitigation by adding the relevant MIDRs to erratum_spec_ssbs_list, and update silicon-errata.rst and the Kconfig text accordingly.
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/20240930111705.3352047-3-mark.rutland@arm.com Signed-off-by: Catalin Marinas catalin.marinas@arm.com [ Mark: trivial backport ] Signed-off-by: Mark Rutland mark.rutland@arm.com --- Documentation/arch/arm64/silicon-errata.rst | 4 ++++ arch/arm64/Kconfig | 2 ++ arch/arm64/kernel/cpu_errata.c | 2 ++ 3 files changed, 8 insertions(+)
diff --git a/Documentation/arch/arm64/silicon-errata.rst b/Documentation/arch/arm64/silicon-errata.rst index 39c52385f11fb..5eefda2f7182b 100644 --- a/Documentation/arch/arm64/silicon-errata.rst +++ b/Documentation/arch/arm64/silicon-errata.rst @@ -146,6 +146,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A715 | #2645198 | ARM64_ERRATUM_2645198 | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-A715 | #3456084 | ARM64_ERRATUM_3194386 | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A720 | #3456091 | ARM64_ERRATUM_3194386 | +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A725 | #3456106 | ARM64_ERRATUM_3194386 | @@ -186,6 +188,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-N2 | #3324339 | ARM64_ERRATUM_3194386 | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Neoverse-N3 | #3456111 | ARM64_ERRATUM_3194386 | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-V1 | #1619801 | N/A | +----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-V1 | #3324341 | ARM64_ERRATUM_3194386 | diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index c8cba20a4d11b..58e56a3673721 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1080,6 +1080,7 @@ config ARM64_ERRATUM_3194386 * ARM Cortex-A78C erratum 3324346 * ARM Cortex-A78C erratum 3324347 * ARM Cortex-A710 erratam 3324338 + * ARM Cortex-A715 errartum 3456084 * ARM Cortex-A720 erratum 3456091 * ARM Cortex-A725 erratum 3456106 * ARM Cortex-X1 erratum 3324344 @@ -1090,6 +1091,7 @@ config ARM64_ERRATUM_3194386 * ARM Cortex-X925 erratum 3324334 * ARM Neoverse-N1 erratum 3324349 * ARM Neoverse N2 erratum 3324339 + * ARM Neoverse-N3 erratum 3456111 * ARM Neoverse-V1 erratum 3324341 * ARM Neoverse V2 erratum 3324336 * ARM Neoverse-V3 erratum 3312417 diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index dfefbdf4073a6..d9b9ec2bd6ff4 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -439,6 +439,7 @@ static const struct midr_range erratum_spec_ssbs_list[] = { MIDR_ALL_VERSIONS(MIDR_CORTEX_A78), MIDR_ALL_VERSIONS(MIDR_CORTEX_A78C), MIDR_ALL_VERSIONS(MIDR_CORTEX_A710), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A715), MIDR_ALL_VERSIONS(MIDR_CORTEX_A720), MIDR_ALL_VERSIONS(MIDR_CORTEX_A725), MIDR_ALL_VERSIONS(MIDR_CORTEX_X1), @@ -449,6 +450,7 @@ static const struct midr_range erratum_spec_ssbs_list[] = { MIDR_ALL_VERSIONS(MIDR_CORTEX_X925), MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N1), MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N2), + MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N3), MIDR_ALL_VERSIONS(MIDR_NEOVERSE_V1), MIDR_ALL_VERSIONS(MIDR_NEOVERSE_V2), MIDR_ALL_VERSIONS(MIDR_NEOVERSE_V3),
From: Easwar Hariharan eahariha@linux.microsoft.com
[ Upstream commit 3eddb108abe3de6723cc4b77e8558ce1b3047987 ]
Add the Microsoft Azure Cobalt 100 CPU to the list of CPUs suffering from erratum 3194386 added in commit 75b3c43eab59 ("arm64: errata: Expand speculative SSBS workaround")
CC: Mark Rutland mark.rutland@arm.com CC: James More james.morse@arm.com CC: Will Deacon will@kernel.org CC: stable@vger.kernel.org # 6.6+ Signed-off-by: Easwar Hariharan eahariha@linux.microsoft.com Link: https://lore.kernel.org/r/20241003225239.321774-1-eahariha@linux.microsoft.c... Signed-off-by: Catalin Marinas catalin.marinas@arm.com [ Mark: trivial backport ] Signed-off-by: Mark Rutland mark.rutland@arm.com --- Documentation/arch/arm64/silicon-errata.rst | 2 ++ arch/arm64/kernel/cpu_errata.c | 1 + 2 files changed, 3 insertions(+)
diff --git a/Documentation/arch/arm64/silicon-errata.rst b/Documentation/arch/arm64/silicon-errata.rst index 5eefda2f7182b..8cd4f365044b6 100644 --- a/Documentation/arch/arm64/silicon-errata.rst +++ b/Documentation/arch/arm64/silicon-errata.rst @@ -293,3 +293,5 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | Microsoft | Azure Cobalt 100| #2253138 | ARM64_ERRATUM_2253138 | +----------------+-----------------+-----------------+-----------------------------+ +| Microsoft | Azure Cobalt 100| #3324339 | ARM64_ERRATUM_3194386 | ++----------------+-----------------+-----------------+-----------------------------+ diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index d9b9ec2bd6ff4..a78f247029aec 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -448,6 +448,7 @@ static const struct midr_range erratum_spec_ssbs_list[] = { MIDR_ALL_VERSIONS(MIDR_CORTEX_X3), MIDR_ALL_VERSIONS(MIDR_CORTEX_X4), MIDR_ALL_VERSIONS(MIDR_CORTEX_X925), + MIDR_ALL_VERSIONS(MIDR_MICROSOFT_AZURE_COBALT_100), MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N1), MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N2), MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N3),
linux-stable-mirror@lists.linaro.org
-
Mark Rutland