From 393eff5a7b357a23db3e786e24b5ba8762cc6820 Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Mon, 3 May 2021 23:02:42 +1000 Subject: powerpc/pesries: Get STF barrier requirement from H_GET_CPU_CHARACTERISTICS This allows the hypervisor / firmware to describe this workarounds to the guest. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210503130243.891868-4-npiggin@gmail.com --- arch/powerpc/include/asm/hvcall.h | 1 + arch/powerpc/platforms/pseries/setup.c | 3 +++ 2 files changed, 4 insertions(+) (limited to 'arch/powerpc') diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h index d769ffbb04f2..2a6346b6472f 100644 --- a/arch/powerpc/include/asm/hvcall.h +++ b/arch/powerpc/include/asm/hvcall.h @@ -402,6 +402,7 @@ #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 +#define H_CPU_BEHAV_NO_STF_BARRIER (1ull << 54) // IBM bit 9 /* 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 287f33645419..631a0d57b6cd 100644 --- a/arch/powerpc/platforms/pseries/setup.c +++ b/arch/powerpc/platforms/pseries/setup.c @@ -555,6 +555,9 @@ static void init_cpu_char_feature_flags(struct h_cpu_char_result *result) if (result->behaviour & H_CPU_BEHAV_NO_L1D_FLUSH_UACCESS) security_ftr_clear(SEC_FTR_L1D_FLUSH_UACCESS); + if (result->behaviour & H_CPU_BEHAV_NO_STF_BARRIER) + security_ftr_clear(SEC_FTR_STF_BARRIER); + if (!(result->behaviour & H_CPU_BEHAV_BNDS_CHK_SPEC_BAR)) security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR); } -- cgit v1.2.3