From: Gleb Natapov <gleb@redhat.com>
Date: Mon, 15 Mar 2010 14:38:29 +0000 (+0200)
Subject: KVM: x86 emulator: fix RCX access during rep emulation
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=c73e197bc525e67b71578126b679446f5b88b508;p=linux-beck.git

KVM: x86 emulator: fix RCX access during rep emulation

During rep emulation access length to RCX depends on current address
mode.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
---

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 0b70a364f0f4..4dce80560d26 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -1852,7 +1852,7 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 
 	if (c->rep_prefix && (c->d & String)) {
 		/* All REP prefixes have the same first termination condition */
-		if (c->regs[VCPU_REGS_RCX] == 0) {
+		if (address_mask(c, c->regs[VCPU_REGS_RCX]) == 0) {
 			kvm_rip_write(ctxt->vcpu, c->eip);
 			goto done;
 		}
@@ -1876,7 +1876,7 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 				goto done;
 			}
 		}
-		c->regs[VCPU_REGS_RCX]--;
+		register_address_increment(c, &c->regs[VCPU_REGS_RCX], -1);
 		c->eip = kvm_rip_read(ctxt->vcpu);
 	}