Commit 366ff5f1b3 ("x86: segment attribute handling adjustments" went a
little too far: We must not do such adjustments for non-present segments.
Reported-by: Roger Pau Monné <roger....@citrix.com>
Signed-off-by: Jan Beulich <jbeul...@suse.com>
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -1374,8 +1374,10 @@ int arch_set_info_hvm_guest(struct vcpu
#define SEG(s, r) ({ \
s = (struct segment_register){ .base = (r)->s ## _base, \
.limit = (r)->s ## _limit, \
- .attr.bytes = (r)->s ## _ar | \
- (x86_seg_##s != x86_seg_tr ? 1 : 2) }; \
+ .attr.bytes = (r)->s ## _ar }; \
+ /* Set accessed / busy bit for present segments. */ \
+ if ( s.attr.fields.p ) \
+ s.attr.fields.type |= (x86_seg_##s != x86_seg_tr ? 1 : 2); \
check_segment(&s, x86_seg_ ## s); })
rc = SEG(cs, regs);
x86/PVH: only set accessed/busy bits for present segments
Commit 366ff5f1b3 ("x86: segment attribute handling adjustments" went a
little too far: We must not do such adjustments for non-present segments.
Reported-by: Roger Pau Monné <roger....@citrix.com>
Signed-off-by: Jan Beulich <jbeul...@suse.com>
--- a/xen/arch/x86/domain.c
+++ b/xen/arch/x86/domain.c
@@ -1374,8 +1374,10 @@ int arch_set_info_hvm_guest(struct vcpu
#define SEG(s, r) ({ \
s = (struct segment_register){ .base = (r)->s ## _base, \
.limit = (r)->s ## _limit, \
- .attr.bytes = (r)->s ## _ar | \
- (x86_seg_##s != x86_seg_tr ? 1 : 2) }; \
+ .attr.bytes = (r)->s ## _ar }; \
+ /* Set accessed / busy bit for present segments. */ \
+ if ( s.attr.fields.p ) \
+ s.attr.fields.type |= (x86_seg_##s != x86_seg_tr ? 1 : 2); \
check_segment(&s, x86_seg_ ## s); })
rc = SEG(cs, regs);
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