Commit 040c8dc8 authored by Nadav Amit's avatar Nadav Amit Committed by Paolo Bonzini

KVM: x86: emulating descriptor load misses long-mode case

In 64-bit mode a #GP should be delivered to the guest "if the code segment
descriptor pointed to by the selector in the 64-bit gate doesn't have the L-bit
set and the D-bit clear." - Intel SDM "Interrupt 13—General Protection
Exception (#GP)".

This patch fixes the behavior of CS loading emulation code. Although the
comment says that segment loading is not supported in long mode, this function
is executed in long mode, so the fix is necassary.
Signed-off-by: default avatarNadav Amit <namit@cs.technion.ac.il>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 77c3913b
...@@ -1504,6 +1504,15 @@ static int __load_segment_descriptor(struct x86_emulate_ctxt *ctxt, ...@@ -1504,6 +1504,15 @@ static int __load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
if (rpl > cpl || dpl != cpl) if (rpl > cpl || dpl != cpl)
goto exception; goto exception;
} }
/* in long-mode d/b must be clear if l is set */
if (seg_desc.d && seg_desc.l) {
u64 efer = 0;
ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
if (efer & EFER_LMA)
goto exception;
}
/* CS(RPL) <- CPL */ /* CS(RPL) <- CPL */
selector = (selector & 0xfffc) | cpl; selector = (selector & 0xfffc) | cpl;
break; break;
......
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