This is a note to let you know that I've just added the patch titled
x86/CPU/AMD: Carve out the erratum 1386 fix
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-cpu-amd-carve-out-the-erratum-1386-fix.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 6fa756f7aa84827d2e839b8a1ef4360092ecf23d
Author: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Date: Wed Nov 1 11:14:59 2023 +0100
x86/CPU/AMD: Carve out the erratum 1386 fix
[ Upstream commit a7c32a1ae9ee43abfe884f5af376877c4301d166 ]
Call it on the affected CPU generations.
No functional changes.
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Reviewed-by: Nikolay Borisov <nik.borisov@xxxxxxxx>
Link: http://lore.kernel.org/r/20231120104152.13740-3-bp@xxxxxxxxx
Stable-dep-of: c7b2edd8377b ("perf/x86/amd/core: Update and fix stalled-cycles-* events for Zen 2 and later")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 5391385707b3f..28c3a1045b060 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -988,6 +988,19 @@ static void init_amd_bd(struct cpuinfo_x86 *c)
clear_rdrand_cpuid_bit(c);
}
+static void fix_erratum_1386(struct cpuinfo_x86 *c)
+{
+ /*
+ * Work around Erratum 1386. The XSAVES instruction malfunctions in
+ * certain circumstances on Zen1/2 uarch, and not all parts have had
+ * updated microcode at the time of writing (March 2023).
+ *
+ * Affected parts all have no supervisor XSAVE states, meaning that
+ * the XSAVEC instruction (which works fine) is equivalent.
+ */
+ clear_cpu_cap(c, X86_FEATURE_XSAVES);
+}
+
void init_spectral_chicken(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_CPU_UNRET_ENTRY
@@ -1008,15 +1021,6 @@ void init_spectral_chicken(struct cpuinfo_x86 *c)
}
}
#endif
- /*
- * Work around Erratum 1386. The XSAVES instruction malfunctions in
- * certain circumstances on Zen1/2 uarch, and not all parts have had
- * updated microcode at the time of writing (March 2023).
- *
- * Affected parts all have no supervisor XSAVE states, meaning that
- * the XSAVEC instruction (which works fine) is equivalent.
- */
- clear_cpu_cap(c, X86_FEATURE_XSAVES);
}
static void init_amd_zn(struct cpuinfo_x86 *c)
@@ -1085,10 +1089,12 @@ static void zenbleed_check(struct cpuinfo_x86 *c)
static void init_amd_zen(struct cpuinfo_x86 *c)
{
+ fix_erratum_1386(c);
}
static void init_amd_zen2(struct cpuinfo_x86 *c)
{
+ fix_erratum_1386(c);
}
static void init_amd_zen3(struct cpuinfo_x86 *c)
