From: John Allen <john.allen@xxxxxxx>
commit ee4d4e8d2c3bec6ee652599ab31991055a72c322 upstream.
Commit
f69759be251d ("x86/CPU/AMD: Move Zenbleed check to the Zen2 init function")
causes a bit in the DE_CFG MSR to get set erroneously after a microcode late
load.
The microcode late load path calls into amd_check_microcode() and subsequently
zen2_zenbleed_check(). Since the above commit removes the cpu_has_amd_erratum()
call from zen2_zenbleed_check(), this will cause all non-Zen2 CPUs to go
through the function and set the bit in the DE_CFG MSR.
Call into the Zenbleed fix path on Zen2 CPUs only.
[ bp: Massage commit message, use cpu_feature_enabled(). ]
Fixes: f69759be251d ("x86/CPU/AMD: Move Zenbleed check to the Zen2 init function")
Signed-off-by: John Allen <john.allen@xxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Acked-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240923164404.27227-1-john.allen@xxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kernel/cpu/amd.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -1374,7 +1374,8 @@ void amd_check_microcode(void)
if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
return;
- on_each_cpu(zenbleed_check_cpu, NULL, 1);
+ if (cpu_feature_enabled(X86_FEATURE_ZEN2))
+ on_each_cpu(zenbleed_check_cpu, NULL, 1);
}
/*
Patches currently in stable-queue which might be from john.allen@xxxxxxx are
queue-6.6/x86-cpu-amd-only-apply-zenbleed-fix-for-zen2-during-late-microcode-load.patch
