KVM: disable writeback for 0x0f 0x01 instructions.

0x0f 0x01 instructions (ie lgdt, lidt, smsw, lmsw and invlpg) does not use writeback. This patch set no_wb=1 when emulating those instructions. This fixes a regression booting the FreeBSD kernel on AMD. Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Avi Kivity <avi@qumranet.com>
git-mirror · Jul 25, 2007 · d37c855 · d37c855
1 parent 4c981b4
commit d37c855
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/drivers/kvm/x86_emulate.c b/drivers/kvm/x86_emulate.c
@@ -1178,6 +1178,8 @@ x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 twobyte_insn:
 	switch (b) {
 	case 0x01: /* lgdt, lidt, lmsw */
+		/* Disable writeback. */
+		no_wb = 1;
 		switch (modrm_reg) {
 			u16 size;
 			unsigned long address;