commit 1844e68ecabbdfdf0228774bcd5cf0f63ffc2e57
author William Grant <wgrant@ubuntu.com> Sun Aug 24 15:13:48 2014 +1000
committer Paolo Bonzini <pbonzini@redhat.com> Mon Aug 25 18:53:42 2014 +0200
tree f72eb352cf25eb7ff4bfe5312e28a547c98cb3e7
parent 3431648272d317ed768fe46183c7a1cea4803732

target-i386: Don't forbid NX bit on PAE PDEs and PTEs

Commit e8f6d00c30ed88910d0d985f4b2bf41654172ceb ("target-i386: raise
page fault for reserved physical address bits") added a check that the
NX bit is not set on PAE PDPEs, but it also added it to rsvd_mask for
the rest of the function. This caused any PDEs or PTEs with NX set to be
erroneously rejected, making PAE guests with NX support unusable.

Signed-off-by: William Grant <wgrant@ubuntu.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

target-i386/helper.c

diff --git a/target-i386/helper.c b/target-i386/helper.c
index 47b982b..30cb0d0 100644
--- a/target-i386/helper.c
+++ b/target-i386/helper.c
@@ -615,8 +615,8 @@
             if (!(pdpe & PG_PRESENT_MASK)) {
                 goto do_fault;
             }
-            rsvd_mask |= PG_HI_USER_MASK | PG_NX_MASK;
-            if (pdpe & rsvd_mask) {
+            rsvd_mask |= PG_HI_USER_MASK;
+            if (pdpe & (rsvd_mask | PG_NX_MASK)) {
                 goto do_fault_rsvd;
             }
             ptep = PG_NX_MASK | PG_USER_MASK | PG_RW_MASK;