From f50803b519c3375df984c2d5717c076d653ae9fb 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 commit 65c7d070850e109a8a75a431f5a7f6eb4c007b77 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- 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 3e8e19f5746c..00c8cda1c9c3 100644 --- a/arch/powerpc/include/asm/hvcall.h +++ b/arch/powerpc/include/asm/hvcall.h @@ -382,6 +382,8 @@ #define H_CPU_BEHAV_BNDS_CHK_SPEC_BAR (1ull << 61) // IBM bit 2 #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 5f0d446a2325..47dfada140e1 100644 --- a/arch/powerpc/platforms/pseries/setup.c +++ b/arch/powerpc/platforms/pseries/setup.c @@ -538,6 +538,12 @@ 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); }