leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

KVM: x86: Do not set access bit on accessed segments

Browse Source 
When segment is loaded, the segment access bit is set unconditionally.  In
fact, it should be set conditionally, based on whether the segment had the
accessed bit set before. In addition, it can improve performance.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Nadav Amit 2014-12-25 02:52:22 +02:00 committed by Paolo Bonzini
parent ab708099a0
commit e2cefa746e
1 changed files with 7 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
arch/x86/kvm/emulate.c
View File

@ -1618,10 +1618,13 @@ static int __load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
if (seg_desc.s) {
/* mark segment as accessed */
seg_desc.type |= 1;
ret = write_segment_descriptor(ctxt, selector, &seg_desc);
if (ret != X86EMUL_CONTINUE)
return ret;
if (!(seg_desc.type & 1)) {
seg_desc.type |= 1;
ret = write_segment_descriptor(ctxt, selector,
&seg_desc);
if (ret != X86EMUL_CONTINUE)
return ret;
}
} else if (ctxt->mode == X86EMUL_MODE_PROT64) {
ret = ctxt->ops->read_std(ctxt, desc_addr+8, &base3,
sizeof(base3), &ctxt->exception);