From 65c7d070850e109a8a75a431f5a7f6eb4c007b77 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Mon, 3 May 2021 23:02:40 +1000 Subject: [PATCH] powerpc/pseries: Get entry and uaccess flush required bits from H_GET_CPU_CHARACTERISTICS This allows the hypervisor / firmware to describe these workarounds to the guest. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210503130243.891868-2-npiggin@gmail.com --- arch/powerpc/include/asm/hvcall.h | 2 ++ arch/powerpc/platforms/pseries/setup.c | 6 ++++++ 2 files changed, 8 insertions(+) diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h index 7c3418d..d769ffb 100644 --- a/arch/powerpc/include/asm/hvcall.h +++ b/arch/powerpc/include/asm/hvcall.h @@ -400,6 +400,8 @@ #define H_CPU_BEHAV_FAVOUR_SECURITY_H (1ull << 60) // IBM bit 3 #define H_CPU_BEHAV_FLUSH_COUNT_CACHE (1ull << 58) // IBM bit 5 #define H_CPU_BEHAV_FLUSH_LINK_STACK (1ull << 57) // IBM bit 6 +#define H_CPU_BEHAV_NO_L1D_FLUSH_ENTRY (1ull << 56) // IBM bit 7 +#define H_CPU_BEHAV_NO_L1D_FLUSH_UACCESS (1ull << 55) // IBM bit 8 /* Flag values used in H_REGISTER_PROC_TBL hcall */ #define PROC_TABLE_OP_MASK 0x18 diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c index 754e493..287f336 100644 --- a/arch/powerpc/platforms/pseries/setup.c +++ b/arch/powerpc/platforms/pseries/setup.c @@ -549,6 +549,12 @@ static void init_cpu_char_feature_flags(struct h_cpu_char_result *result) if (!(result->behaviour & H_CPU_BEHAV_L1D_FLUSH_PR)) security_ftr_clear(SEC_FTR_L1D_FLUSH_PR); + if (result->behaviour & H_CPU_BEHAV_NO_L1D_FLUSH_ENTRY) + security_ftr_clear(SEC_FTR_L1D_FLUSH_ENTRY); + + if (result->behaviour & H_CPU_BEHAV_NO_L1D_FLUSH_UACCESS) + security_ftr_clear(SEC_FTR_L1D_FLUSH_UACCESS); + if (!(result->behaviour & H_CPU_BEHAV_BNDS_CHK_SPEC_BAR)) security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR); } -- 2.7.4