From: James Morse james.morse@arm.com
commit 39fdb65f52e9a53d32a6ba719f96669fd300ae78 upstream.
Cortex-A510 is affected by an erratum where in rare circumstances the CPUs may not handle a race between a break-before-make sequence on one CPU, and another CPU accessing the same page. This could allow a store to a page that has been unmapped.
Work around this by adding the affected CPUs to the list that needs TLB sequences to be done twice.
Signed-off-by: James Morse james.morse@arm.com Link: https://lore.kernel.org/r/20220704155732.21216-1-james.morse@arm.com Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Lucas Wei lucaswei@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- Documentation/arm64/silicon-errata.rst | 2 ++ arch/arm64/Kconfig | 17 +++++++++++++++++ arch/arm64/kernel/cpu_errata.c | 8 +++++++- 3 files changed, 26 insertions(+), 1 deletion(-)
--- a/Documentation/arm64/silicon-errata.rst +++ b/Documentation/arm64/silicon-errata.rst @@ -92,6 +92,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A77 | #1508412 | ARM64_ERRATUM_1508412 | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-A510 | #2441009 | ARM64_ERRATUM_2441009 | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-N1 | #1188873,1418040| ARM64_ERRATUM_1418040 | +----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-N1 | #1349291 | N/A | --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -666,6 +666,23 @@ config ARM64_ERRATUM_1508412
If unsure, say Y.
+config ARM64_ERRATUM_2441009 + bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI" + default y + select ARM64_WORKAROUND_REPEAT_TLBI + help + This option adds a workaround for ARM Cortex-A510 erratum #2441009. + + Under very rare circumstances, affected Cortex-A510 CPUs + may not handle a race between a break-before-make sequence on one + CPU, and another CPU accessing the same page. This could allow a + store to a page that has been unmapped. + + Work around this by adding the affected CPUs to the list that needs + TLB sequences to be done twice. + + If unsure, say Y. + config CAVIUM_ERRATUM_22375 bool "Cavium erratum 22375, 24313" default y --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -214,6 +214,12 @@ static const struct arm64_cpu_capabiliti ERRATA_MIDR_RANGE(MIDR_QCOM_KRYO_4XX_GOLD, 0xc, 0xe, 0xf, 0xe), }, #endif +#ifdef CONFIG_ARM64_ERRATUM_2441009 + { + /* Cortex-A510 r0p0 -> r1p1. Fixed in r1p2 */ + ERRATA_MIDR_RANGE(MIDR_CORTEX_A510, 0, 0, 1, 1), + }, +#endif {}, }; #endif @@ -429,7 +435,7 @@ const struct arm64_cpu_capabilities arm6 #endif #ifdef CONFIG_ARM64_WORKAROUND_REPEAT_TLBI { - .desc = "Qualcomm erratum 1009, or ARM erratum 1286807", + .desc = "Qualcomm erratum 1009, or ARM erratum 1286807, 2441009", .capability = ARM64_WORKAROUND_REPEAT_TLBI, .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, .matches = cpucap_multi_entry_cap_matches,