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| author | Pawan Gupta <pawan.kumar.gupta@linux.intel.com> | 2024-03-11 22:29:43 +0300 |
|---|---|---|
| committer | Sasha Levin <sashal@kernel.org> | 2024-03-15 17:48:22 +0300 |
| commit | 4a5b5bfea063745471af6395d22ebaea8242225e (patch) | |
| tree | 3b33941f856291097f14c34db27e35683f2ab8e7 /arch/x86/kvm/x86.c | |
| parent | 77018fb9efe50cf24e61275ee09253cf1fbb6854 (diff) | |
| download | linux-4a5b5bfea063745471af6395d22ebaea8242225e.tar.xz | |
KVM/x86: Export RFDS_NO and RFDS_CLEAR to guests
commit 2a0180129d726a4b953232175857d442651b55a0 upstream.
Mitigation for RFDS requires RFDS_CLEAR capability which is enumerated
by MSR_IA32_ARCH_CAPABILITIES bit 27. If the host has it set, export it
to guests so that they can deploy the mitigation.
RFDS_NO indicates that the system is not vulnerable to RFDS, export it
to guests so that they don't deploy the mitigation unnecessarily. When
the host is not affected by X86_BUG_RFDS, but has RFDS_NO=0, synthesize
RFDS_NO to the guest.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/kvm/x86.c')
| -rw-r--r-- | arch/x86/kvm/x86.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 3d8472d00024..9b6639d87a62 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1620,7 +1620,8 @@ static bool kvm_is_immutable_feature_msr(u32 msr) ARCH_CAP_SKIP_VMENTRY_L1DFLUSH | ARCH_CAP_SSB_NO | ARCH_CAP_MDS_NO | \ ARCH_CAP_PSCHANGE_MC_NO | ARCH_CAP_TSX_CTRL_MSR | ARCH_CAP_TAA_NO | \ ARCH_CAP_SBDR_SSDP_NO | ARCH_CAP_FBSDP_NO | ARCH_CAP_PSDP_NO | \ - ARCH_CAP_FB_CLEAR | ARCH_CAP_RRSBA | ARCH_CAP_PBRSB_NO | ARCH_CAP_GDS_NO) + ARCH_CAP_FB_CLEAR | ARCH_CAP_RRSBA | ARCH_CAP_PBRSB_NO | ARCH_CAP_GDS_NO | \ + ARCH_CAP_RFDS_NO | ARCH_CAP_RFDS_CLEAR) static u64 kvm_get_arch_capabilities(void) { @@ -1652,6 +1653,8 @@ static u64 kvm_get_arch_capabilities(void) data |= ARCH_CAP_SSB_NO; if (!boot_cpu_has_bug(X86_BUG_MDS)) data |= ARCH_CAP_MDS_NO; + if (!boot_cpu_has_bug(X86_BUG_RFDS)) + data |= ARCH_CAP_RFDS_NO; if (!boot_cpu_has(X86_FEATURE_RTM)) { /* |