[xen stable-4.20] x86/ucode: Exclude Zen6 from entrysign digest checking

[patchbot@xxxxxxx]

commit f8a6e2f4ad081bc60411c97a4a351ea878670ff2
Author:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
AuthorDate: Tue Jun 30 15:00:31 2026 +0200
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Tue Jun 30 15:00:31 2026 +0200

    x86/ucode: Exclude Zen6 from entrysign digest checking
    
    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>
    Reviewed-by: Teddy Astie <teddy.astie@xxxxxxxxxx>
    Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
    master commit: 6ba5e9c7b887d85c7e7f385892d7edbf2573a279
    master date: 2026-06-16 18:33:39 +0100
---
 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 eeb2a75fbe..471f6e6541 100644
--- a/xen/arch/x86/cpu/microcode/amd.c
+++ b/xen/arch/x86/cpu/microcode/amd.c
@@ -129,7 +129,8 @@ static bool check_digest(const struct container_microcode 
*mc)
      * the digest of the patch against a list of known provenance.
      */
     if ( boot_cpu_data.x86 < 0x17 || boot_cpu_data.x86 > 0x1a ||
-         entrysign_mitigiated_in_firmware || !opt_digest_check )
+         is_zen6_uarch() || entrysign_mitigiated_in_firmware ||
+         !opt_digest_check )
         return true;
 
     pd = bsearch(&patch->patch_id, patch_digests, ARRAY_SIZE(patch_digests),
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.20