[PATCH v2 25/35] x86/bugs: Add attack vector controls for rfds

David Kaplan posted 35 patches 2 weeks, 4 days ago
[PATCH v2 25/35] x86/bugs: Add attack vector controls for rfds
Posted by David Kaplan 2 weeks, 4 days ago
Use attack vector controls to determine if rfds mitigation is required.

Signed-off-by: David Kaplan <david.kaplan@amd.com>
---
 arch/x86/kernel/cpu/bugs.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index ab1a8ae31588..ecf7046673b9 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -718,8 +718,14 @@ static void __init rfds_select_mitigation(void)
 	if (rfds_mitigation == RFDS_MITIGATION_OFF)
 		return;
 
-	if (rfds_mitigation == RFDS_MITIGATION_AUTO)
-		rfds_mitigation = RFDS_MITIGATION_VERW;
+	if (rfds_mitigation == RFDS_MITIGATION_AUTO) {
+		if (should_mitigate_vuln(X86_BUG_RFDS))
+			rfds_mitigation = RFDS_MITIGATION_VERW;
+		else {
+			rfds_mitigation = RFDS_MITIGATION_OFF;
+			return;
+		}
+	}
 
 	if (!(x86_arch_cap_msr & ARCH_CAP_RFDS_CLEAR))
 		rfds_mitigation = RFDS_MITIGATION_UCODE_NEEDED;
-- 
2.34.1