lkml.org 
[lkml]   [2008]   [Sep]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 01/25] KVM: x86 emulator: Add std and cld instructions (opcodes 0xfc-0xfd)
Date
From: Mohammed Gamal <m.gamal005@gmail.com>

This adds the std and cld instructions to the emulator.

Encountered while running the BIOS with invalid guest
state emulation enabled.

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
---
arch/x86/kvm/x86_emulate.c | 10 +++++++++-
1 files changed, 9 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kvm/x86_emulate.c b/arch/x86/kvm/x86_emulate.c
index 66e0bd6..944f1f4 100644
--- a/arch/x86/kvm/x86_emulate.c
+++ b/arch/x86/kvm/x86_emulate.c
@@ -187,7 +187,7 @@ static u16 opcode_table[256] = {
ImplicitOps, ImplicitOps, Group | Group3_Byte, Group | Group3,
/* 0xF8 - 0xFF */
ImplicitOps, 0, ImplicitOps, ImplicitOps,
- 0, 0, Group | Group4, Group | Group5,
+ ImplicitOps, ImplicitOps, Group | Group4, Group | Group5,
};

static u16 twobyte_table[256] = {
@@ -1762,6 +1762,14 @@ special_insn:
ctxt->eflags |= X86_EFLAGS_IF;
c->dst.type = OP_NONE; /* Disable writeback. */
break;
+ case 0xfc: /* cld */
+ ctxt->eflags &= ~EFLG_DF;
+ c->dst.type = OP_NONE; /* Disable writeback. */
+ break;
+ case 0xfd: /* std */
+ ctxt->eflags |= EFLG_DF;
+ c->dst.type = OP_NONE; /* Disable writeback. */
+ break;
case 0xfe ... 0xff: /* Grp4/Grp5 */
rc = emulate_grp45(ctxt, ops);
if (rc != 0)
--
1.6.0.1


\
 
 \ /
  Last update: 2008-09-28 17:51    [W:0.097 / U:0.228 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site