This is a note to let you know that I've just added the patch titled arm64: errata: Add detection for TRBE trace data corruption to the 5.16-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: arm64-errata-add-detection-for-trbe-trace-data-corru.patch and it can be found in the queue-5.16 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 1cddfe24145084ac23c16d1db5e60717a7244a08 Author: Anshuman Khandual <anshuman.khandual@xxxxxxx> Date: Tue Jan 25 19:50:34 2022 +0530 arm64: errata: Add detection for TRBE trace data corruption [ Upstream commit 708e8af4924ec2fdd5b81fe09192c6bac2f86935 ] TRBE implementations affected by Arm erratum #1902691 might corrupt trace data or deadlock, when it's being written into the memory. So effectively TRBE is broken and hence cannot be used to capture trace data. This adds a new errata ARM64_ERRATUM_1902691 in arm64 errata framework. Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> Cc: Suzuki Poulose <suzuki.poulose@xxxxxxx> Cc: coresight@xxxxxxxxxxxxxxxx Cc: linux-doc@xxxxxxxxxxxxxxx Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Reviewed-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx> Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx> Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx> Link: https://lore.kernel.org/r/1643120437-14352-5-git-send-email-anshuman.khandual@xxxxxxx Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst index d5c6befc44eb8..1b0e53ececda9 100644 --- a/Documentation/arm64/silicon-errata.rst +++ b/Documentation/arm64/silicon-errata.rst @@ -56,6 +56,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A510 | #2038923 | ARM64_ERRATUM_2038923 | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-A510 | #1902691 | ARM64_ERRATUM_1902691 | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A53 | #826319 | ARM64_ERRATUM_826319 | +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A53 | #827319 | ARM64_ERRATUM_827319 | diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 2b75e8a9bf88c..7d710589e1818 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -819,6 +819,24 @@ config ARM64_ERRATUM_2038923 If unsure, say Y. +config ARM64_ERRATUM_1902691 + bool "Cortex-A510: 1902691: workaround TRBE trace corruption" + depends on COMPILE_TEST # Until the CoreSight TRBE driver changes are in + default y + help + This option adds the workaround for ARM Cortex-A510 erratum 1902691. + + Affected Cortex-A510 core might cause trace data corruption, when being written + into the memory. Effectively TRBE is broken and hence cannot be used to capture + trace data. + + Work around this problem in the driver by just preventing TRBE initialization on + affected cpus. The firmware must have disabled the access to TRBE for the kernel + on such implementations. This will cover the kernel for any firmware that doesn't + do this already. + + If unsure, say Y. + config CAVIUM_ERRATUM_22375 bool "Cavium erratum 22375, 24313" default y diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index a64bf132c6336..066098198c248 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -617,6 +617,15 @@ const struct arm64_cpu_capabilities arm64_errata[] = { /* Cortex-A510 r0p0 - r0p2 */ ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A510, 0, 0, 2) }, +#endif +#ifdef CONFIG_ARM64_ERRATUM_1902691 + { + .desc = "ARM erratum 1902691", + .capability = ARM64_WORKAROUND_1902691, + + /* Cortex-A510 r0p0 - r0p1 */ + ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A510, 0, 0, 1) + }, #endif { } diff --git a/arch/arm64/tools/cpucaps b/arch/arm64/tools/cpucaps index 45a06d36d0807..e7719e8f18def 100644 --- a/arch/arm64/tools/cpucaps +++ b/arch/arm64/tools/cpucaps @@ -57,6 +57,7 @@ WORKAROUND_1508412 WORKAROUND_1542419 WORKAROUND_2064142 WORKAROUND_2038923 +WORKAROUND_1902691 WORKAROUND_TRBE_OVERWRITE_FILL_MODE WORKAROUND_TSB_FLUSH_FAILURE WORKAROUND_TRBE_WRITE_OUT_OF_RANGE