From 736bcdd3a9fc672af33fb83230ecd0570ec38ec6 Mon Sep 17 00:00:00 2001 From: Jordan Niethe Date: Fri, 6 Dec 2019 14:17:22 +1100 Subject: powerpc/mm: Remove kvm radix prefetch workaround for Power9 DD2.2 Commit a25bd72badfa ("powerpc/mm/radix: Workaround prefetch issue with KVM") introduced a number of workarounds as coming out of a guest with the mmu enabled would make the cpu would start running in hypervisor state with the PID value from the guest. The cpu will then start prefetching for the hypervisor with that PID value. In Power9 DD2.2 the cpu behaviour was modified to fix this. When accessing Quadrant 0 in hypervisor mode with LPID != 0 prefetching will not be performed. This means that we can get rid of the workarounds for Power9 DD2.2 and later revisions. Add a new cpu feature CPU_FTR_P9_RADIX_PREFETCH_BUG to indicate if the workarounds are needed. Signed-off-by: Jordan Niethe Acked-by: Paul Mackerras Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20191206031722.25781-1-jniethe5@gmail.com --- arch/powerpc/include/asm/cputable.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'arch/powerpc/include/asm/cputable.h') diff --git a/arch/powerpc/include/asm/cputable.h b/arch/powerpc/include/asm/cputable.h index cf00ff0d121d..40a4d3c6fd99 100644 --- a/arch/powerpc/include/asm/cputable.h +++ b/arch/powerpc/include/asm/cputable.h @@ -212,6 +212,7 @@ static inline void cpu_feature_keys_init(void) { } #define CPU_FTR_P9_TLBIE_STQ_BUG LONG_ASM_CONST(0x0000400000000000) #define CPU_FTR_P9_TIDR LONG_ASM_CONST(0x0000800000000000) #define CPU_FTR_P9_TLBIE_ERAT_BUG LONG_ASM_CONST(0x0001000000000000) +#define CPU_FTR_P9_RADIX_PREFETCH_BUG LONG_ASM_CONST(0x0002000000000000) #ifndef __ASSEMBLY__ @@ -459,8 +460,10 @@ static inline void cpu_feature_keys_init(void) { } CPU_FTR_DBELL | CPU_FTR_HAS_PPR | CPU_FTR_ARCH_207S | \ CPU_FTR_TM_COMP | CPU_FTR_ARCH_300 | CPU_FTR_PKEY | \ CPU_FTR_P9_TLBIE_STQ_BUG | CPU_FTR_P9_TLBIE_ERAT_BUG | CPU_FTR_P9_TIDR) -#define CPU_FTRS_POWER9_DD2_0 CPU_FTRS_POWER9 -#define CPU_FTRS_POWER9_DD2_1 (CPU_FTRS_POWER9 | CPU_FTR_POWER9_DD2_1) +#define CPU_FTRS_POWER9_DD2_0 (CPU_FTRS_POWER9 | CPU_FTR_P9_RADIX_PREFETCH_BUG) +#define CPU_FTRS_POWER9_DD2_1 (CPU_FTRS_POWER9 | \ + CPU_FTR_P9_RADIX_PREFETCH_BUG | \ + CPU_FTR_POWER9_DD2_1) #define CPU_FTRS_POWER9_DD2_2 (CPU_FTRS_POWER9 | CPU_FTR_POWER9_DD2_1 | \ CPU_FTR_P9_TM_HV_ASSIST | \ CPU_FTR_P9_TM_XER_SO_BUG) -- cgit v1.2.3