4.4-stable review patch. If anyone has any objections, please let me know.
------------------ [ Upstream commit 104a0c02e8b1936c049e18a6d4e4ab040fb61213 ] On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI instructions may cause the icache to become corrupted if it contains data for a non-current ASID. This patch implements the workaround (which invalidates the local icache when switching the mm) by using code patching. Signed-off-by: Andrew Pinski <[email protected]> Signed-off-by: David Daney <[email protected]> Reviewed-by: Will Deacon <[email protected]> Signed-off-by: Catalin Marinas <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/arm64/Kconfig | 11 +++++++++++ arch/arm64/include/asm/cpufeature.h | 3 ++- arch/arm64/kernel/cpu_errata.c | 9 +++++++++ arch/arm64/mm/proc.S | 12 ++++++++++++ 4 files changed, 34 insertions(+), 1 deletion(-) --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -401,6 +401,17 @@ config CAVIUM_ERRATUM_23154 If unsure, say Y. +config CAVIUM_ERRATUM_27456 + bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption" + default y + help + On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI + instructions may cause the icache to become corrupted if it + contains data for a non-current ASID. The fix is to + invalidate the icache when changing the mm context. + + If unsure, say Y. + endmenu --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -30,8 +30,9 @@ #define ARM64_HAS_LSE_ATOMICS 5 #define ARM64_WORKAROUND_CAVIUM_23154 6 #define ARM64_WORKAROUND_834220 7 +#define ARM64_WORKAROUND_CAVIUM_27456 8 -#define ARM64_NCAPS 8 +#define ARM64_NCAPS 9 #ifndef __ASSEMBLY__ --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -100,6 +100,15 @@ const struct arm64_cpu_capabilities arm6 MIDR_RANGE(MIDR_THUNDERX, 0x00, 0x01), }, #endif +#ifdef CONFIG_CAVIUM_ERRATUM_27456 + { + /* Cavium ThunderX, T88 pass 1.x - 2.1 */ + .desc = "Cavium erratum 27456", + .capability = ARM64_WORKAROUND_CAVIUM_27456, + MIDR_RANGE(MIDR_THUNDERX, 0x00, + (1 << MIDR_VARIANT_SHIFT) | 1), + }, +#endif { } }; --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -25,6 +25,8 @@ #include <asm/hwcap.h> #include <asm/pgtable-hwdef.h> #include <asm/pgtable.h> +#include <asm/cpufeature.h> +#include <asm/alternative.h> #include "proc-macros.S" @@ -137,7 +139,17 @@ ENTRY(cpu_do_switch_mm) bfi x0, x1, #48, #16 // set the ASID msr ttbr0_el1, x0 // set TTBR0 isb +alternative_if_not ARM64_WORKAROUND_CAVIUM_27456 ret + nop + nop + nop +alternative_else + ic iallu + dsb nsh + isb + ret +alternative_endif ENDPROC(cpu_do_switch_mm) .section ".text.init", #alloc, #execinstr
