From ae6229a3e45318b1101291b99a0e894399dcb1db Mon Sep 17 00:00:00 2001 From: Pawan Gupta Date: Wed, 13 Mar 2024 07:53:23 -0700 Subject: [PATCH 007/100] target/i386: Export RFDS bit to guests RH-Author: Paolo Bonzini RH-MergeRequest: 245: SEV-SNP support RH-Jira: RHEL-39544 RH-Acked-by: Thomas Huth RH-Acked-by: Bandan Das RH-Acked-by: Vitaly Kuznetsov RH-Commit: [7/91] 7eb6cae8821a2e953d3ff2033fa2e973011ad771 (bonzini/rhel-qemu-kvm) Register File Data Sampling (RFDS) is a CPU side-channel vulnerability that may expose stale register value. CPUs that set RFDS_NO bit in MSR IA32_ARCH_CAPABILITIES indicate that they are not vulnerable to RFDS. Similarly, RFDS_CLEAR indicates that CPU is affected by RFDS, and has the microcode to help mitigate RFDS. Make RFDS_CLEAR and RFDS_NO bits available to guests. Signed-off-by: Pawan Gupta Reviewed-by: Xiaoyao Li Reviewed-by: Zhao Liu Message-ID: <9a38877857392b5c2deae7e7db1b170d15510314.1710341348.git.pawan.kumar.gupta@linux.intel.com> Signed-off-by: Paolo Bonzini (cherry picked from commit 41bdd9812863c150284a9339a048ed88c40f4df7) Signed-off-by: Paolo Bonzini --- target/i386/cpu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/target/i386/cpu.c b/target/i386/cpu.c index efbadc3ed7..489c853b42 100644 --- a/target/i386/cpu.c +++ b/target/i386/cpu.c @@ -1158,8 +1158,8 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = { NULL, "sbdr-ssdp-no", "fbsdp-no", "psdp-no", NULL, "fb-clear", NULL, NULL, NULL, NULL, NULL, NULL, - "pbrsb-no", NULL, "gds-no", NULL, - NULL, NULL, NULL, NULL, + "pbrsb-no", NULL, "gds-no", "rfds-no", + "rfds-clear", NULL, NULL, NULL, }, .msr = { .index = MSR_IA32_ARCH_CAPABILITIES, -- 2.39.3