[PATCH for-4.22] x86/ucode: Exclude Zen6 from entrysign digest checking

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

There is a 3rd path which should have gained an is_zen6_uarch() check to
exclude Zen6 from entrysign mitigations.

Fixes: bd15fdedafb3 ("x86/ucode: Exclude Zen6 from entrysign mitigations")
Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
CC: Jan Beulich <jbeulich@xxxxxxxx>
CC: Roger Pau Monné <roger.pau@xxxxxxxxxx>
CC: Teddy Astie <teddy.astie@xxxxxxxxxx>
CC: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>

For 4.22.  This wants backporting too.
---
 xen/arch/x86/cpu/microcode/amd.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/xen/arch/x86/cpu/microcode/amd.c b/xen/arch/x86/cpu/microcode/amd.c
index 2ba1fa825f2f..2d4911022835 100644
--- a/xen/arch/x86/cpu/microcode/amd.c
+++ b/xen/arch/x86/cpu/microcode/amd.c
@@ -128,7 +128,8 @@ static bool check_digest(const struct container_microcode 
*mc)
      * the digest of the patch against a list of known provenance.
      */
     if ( boot_cpu_data.family < 0x17 || boot_cpu_data.family > 0x1a ||
-         entrysign_mitigated_in_firmware || !opt_digest_check )
+         is_zen6_uarch() || entrysign_mitigated_in_firmware ||
+         !opt_digest_check )
         return true;
 
     pd = bsearch(&patch->patch_id, patch_digests, ARRAY_SIZE(patch_digests),

base-commit: 1cfceee62d8b086a1713d04522f741a09d50cbb3
-- 
2.39.5