[PATCH 5.10 135/135] x86/srso: Correct the mitigation status when SMT is disabled

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5.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Borislav Petkov (AMD) <bp@xxxxxxxxx>

commit 6405b72e8d17bd1875a56ae52d23ec3cd51b9d66 upstream.

Specify how is SRSO mitigated when SMT is disabled. Also, correct the
SMT check for that.

Fixes: e9fbc47b818b ("x86/srso: Disable the mitigation on unaffected configurations")
Suggested-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Acked-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230814200813.p5czl47zssuej7nv@treble
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 arch/x86/kernel/cpu/bugs.c |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -2328,8 +2328,7 @@ static void __init srso_select_mitigatio
 		 * Zen1/2 with SMT off aren't vulnerable after the right
 		 * IBPB microcode has been applied.
 		 */
-		if ((boot_cpu_data.x86 < 0x19) &&
-		    (!cpu_smt_possible() || (cpu_smt_control == CPU_SMT_DISABLED))) {
+		if (boot_cpu_data.x86 < 0x19 && !cpu_smt_possible()) {
 			setup_force_cpu_cap(X86_FEATURE_SRSO_NO);
 			return;
 		}
@@ -2619,7 +2618,7 @@ static ssize_t gds_show_state(char *buf)
 static ssize_t srso_show_state(char *buf)
 {
 	if (boot_cpu_has(X86_FEATURE_SRSO_NO))
-		return sysfs_emit(buf, "Not affected\n");
+		return sysfs_emit(buf, "Mitigation: SMT disabled\n");
 
 	return sysfs_emit(buf, "%s%s\n",
 			  srso_strings[srso_mitigation],





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