From 20109a859a9b514eb10c22b8a14b5704ffe93897 Mon Sep 17 00:00:00 2001 From: Rich Wiley Date: Tue, 23 Mar 2021 17:28:09 -0700 Subject: arm64: kernel: disable CNP on Carmel On NVIDIA Carmel cores, CNP behaves differently than it does on standard ARM cores. On Carmel, if two cores have CNP enabled and share an L2 TLB entry created by core0 for a specific ASID, a non-shareable TLBI from core1 may still see the shared entry. On standard ARM cores, that TLBI will invalidate the shared entry as well. This causes issues with patchsets that attempt to do local TLBIs based on cpumasks instead of broadcast TLBIs. Avoid these issues by disabling CNP support for NVIDIA Carmel cores. Signed-off-by: Rich Wiley Link: https://lore.kernel.org/r/20210324002809.30271-1-rwiley@nvidia.com [will: Fix pre-existing whitespace issue] Signed-off-by: Will Deacon --- arch/arm64/include/asm/cpucaps.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/arm64/include/asm/cpucaps.h') diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h index b77d997b173b..c40f2490cd7b 100644 --- a/arch/arm64/include/asm/cpucaps.h +++ b/arch/arm64/include/asm/cpucaps.h @@ -66,7 +66,8 @@ #define ARM64_WORKAROUND_1508412 58 #define ARM64_HAS_LDAPR 59 #define ARM64_KVM_PROTECTED_MODE 60 +#define ARM64_WORKAROUND_NVIDIA_CARMEL_CNP 61 -#define ARM64_NCAPS 61 +#define ARM64_NCAPS 62 #endif /* __ASM_CPUCAPS_H */ -- cgit