[xen staging] xen/x86/hvm: Propagate emulated CR2 writes to the VMCB

[patchbot@xxxxxxx]

commit e4d90abb26a814ae6f33ce6aa66c9095aa5cae5f
Author:     Stefano Stabellini <stefano.stabellini@xxxxxxx>
AuthorDate: Tue Oct 20 14:33:15 2026 -0700
Commit:     Stefano Stabellini <stefano.stabellini@xxxxxxx>
CommitDate: Fri Oct 23 17:23:43 2026 -0700

    xen/x86/hvm: Propagate emulated CR2 writes to the VMCB
    
    hvmemul_write_cr() updates guest_cr[2] but, unlike every other writer of
    it, doesn't call hvm_update_guest_cr(). On SVM, CR2 is loaded from
    the VMCB, so the emulated write never reaches the guest, and the next
    VMExit overwrites guest_cr[2] with the stale VMCB value.
    
    Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxx>
    Acked-by: Roger Pau Monné <roger@xxxxxxxxxxxxxx>
---
 xen/arch/x86/hvm/emulate.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/xen/arch/x86/hvm/emulate.c b/xen/arch/x86/hvm/emulate.c
index c09ea002ec..cd2831d34b 100644
--- a/xen/arch/x86/hvm/emulate.c
+++ b/xen/arch/x86/hvm/emulate.c
@@ -2350,6 +2350,7 @@ static int cf_check hvmemul_write_cr(
 
     case 2:
         curr->arch.hvm.guest_cr[2] = val;
+        hvm_update_guest_cr(curr, 2);
         rc = X86EMUL_OKAY;
         break;
 
--
generated by git-patchbot for /home/xen/git/xen.git#staging