[Qemu-devel] [PULL 1/6] target-i386: Allow execute from user mode when SMEP is enabled.

[Paolo Bonzini <pbonzini@redhat.com>]

From: Ricky Zhou <ricky@rzhou.org>

Previously, execute would be disabled for all pages with SMEP enabled,
regardless of what mode the access took place in.

Signed-off-by: Ricky Zhou <ricky@rzhou.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 target-i386/helper.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/target-i386/helper.c b/target-i386/helper.c
index 11ca864..47b982b 100644
--- a/target-i386/helper.c
+++ b/target-i386/helper.c
@@ -750,7 +750,8 @@ do_check_protect_pse36:
     /* the page can be put in the TLB */
     prot = PAGE_READ;
     if (!(ptep & PG_NX_MASK) &&
-        !((env->cr[4] & CR4_SMEP_MASK) && (ptep & PG_USER_MASK))) {
+        (mmu_idx == MMU_USER_IDX ||
+         !((env->cr[4] & CR4_SMEP_MASK) && (ptep & PG_USER_MASK)))) {
         prot |= PAGE_EXEC;
     }
     if (pte & PG_DIRTY_MASK) {
-- 
1.9.3