[PATCH][RESEND] x86 emulator: Add in/out instructions (opcodes 0xe4-0xe7, 0xec-0xef)

[PATCH][RESEND] x86 emulator: Add in/out instructions (opcodes 0xe4-0xe7, 0xec-0xef)

[Mohammed Gamal]

The patch adds in/out instructions to the x86 emulator.

The instruction was encountered while running the BIOS while using
the invalid guest state emulation patch.

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
---
 arch/x86/kvm/x86_emulate.c |   35 +++++++++++++++++++++++++++++++++--
 1 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/x86_emulate.c b/arch/x86/kvm/x86_emulate.c
index 005f1db..dfc1090 100644
--- a/arch/x86/kvm/x86_emulate.c
+++ b/arch/x86/kvm/x86_emulate.c
@@ -170,11 +170,14 @@ static u16 opcode_table[256] = {
 	/* 0xD8 - 0xDF */
 	0, 0, 0, 0, 0, 0, 0, 0,
 	/* 0xE0 - 0xE7 */
-	0, 0, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0,
+	SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps,
+	SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps,
 	/* 0xE8 - 0xEF */
 	ImplicitOps | Stack, SrcImm | ImplicitOps,
 	ImplicitOps, SrcImmByte | ImplicitOps,
-	0, 0, 0, 0,
+	SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps,
+	SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps,
 	/* 0xF0 - 0xF7 */
 	0, 0, 0, 0,
 	ImplicitOps, ImplicitOps, Group | Group3_Byte, Group | Group3,
@@ -1252,6 +1255,8 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 	u64 msr_data;
 	unsigned long saved_eip = 0;
 	struct decode_cache *c = &ctxt->decode;
+	unsigned int port;
+	int io_direction;
 	int rc = 0;
 
 	/* Shadow copy of register state. Committed on successful emulation.
@@ -1680,6 +1685,16 @@ special_insn:
 		c->src.val = c->regs[VCPU_REGS_RCX];
 		emulate_grp2(ctxt);
 		break;
+	case 0xe4: 	/* inb */
+	case 0xe5: 	/* in */
+		port = insn_fetch(u8, 1, c->eip);
+		io_direction = 1;
+		goto do_io;
+	case 0xe6: /* outb */
+	case 0xe7: /* out */
+		port = insn_fetch(u8, 1, c->eip);
+		io_direction = 0;
+		goto do_io;
 	case 0xe8: /* call (near) */ {
 		long int rel;
 		switch (c->op_bytes) {
@@ -1730,6 +1745,22 @@ special_insn:
 		jmp_rel(c, c->src.val);
 		c->dst.type = OP_NONE; /* Disable writeback. */
 		break;
+	case 0xec: /* in al,dx */
+	case 0xed: /* in (e/r)ax,dx */
+		port = c->regs[VCPU_REGS_RDX];
+		io_direction = 1;
+		goto do_io;
+	case 0xee: /* out al,dx */
+	case 0xef: /* out (e/r)ax,dx */
+		port = c->regs[VCPU_REGS_RDX];
+		io_direction = 0;
+	do_io:	if (kvm_emulate_pio(ctxt->vcpu, NULL, io_direction,
+				   (c->d & ByteOp) ? 1 : c->op_bytes,
+				   port) != 0) {
+			c->eip = saved_eip;
+			goto cannot_emulate;
+		}
+		return 0;
 	case 0xf4:              /* hlt */
 		ctxt->vcpu->arch.halt_request = 1;
 		break;
-- 
1.5.4.3

Re: [PATCH][RESEND] x86 emulator: Add in/out instructions (opcodes 0xe4-0xe7, 0xec-0xef)

[Avi Kivity]

Mohammed Gamal wrote:
> The patch adds in/out instructions to the x86 emulator.
>
> The instruction was encountered while running the BIOS while using
> the invalid guest state emulation patch.
>   

We still don't have a testcase for this.

-- 
error compiling committee.c: too many arguments to function

Re: [PATCH][RESEND] x86 emulator: Add in/out instructions (opcodes 0xe4-0xe7, 0xec-0xef)

[Mohammed Gamal]

On Wed, Aug 20, 2008 at 11:42 AM, Avi Kivity <avi@qumranet.com> wrote:
> Mohammed Gamal wrote:
>>
>> The patch adds in/out instructions to the x86 emulator.
>>
>> The instruction was encountered while running the BIOS while using
>> the invalid guest state emulation patch.
>>
>
> We still don't have a testcase for this.
>
To be clear, do you want an emulator test case (in
user/test/x86/emulator.c) for every instruction added to the emulator?

Re: [PATCH][RESEND] x86 emulator: Add in/out instructions (opcodes 0xe4-0xe7, 0xec-0xef)

[Avi Kivity]

Mohammed Gamal wrote:
> On Wed, Aug 20, 2008 at 11:42 AM, Avi Kivity <avi@qumranet.com> wrote:
>   
>> Mohammed Gamal wrote:
>>     
>>> The patch adds in/out instructions to the x86 emulator.
>>>
>>> The instruction was encountered while running the BIOS while using
>>> the invalid guest state emulation patch.
>>>
>>>       
>> We still don't have a testcase for this.
>>
>>     
> To be clear, do you want an emulator test case (in
> user/test/x86/emulator.c) for every instruction added to the emulator?
>   

Yes.  We've been bitten by rarely-used instructions being broken.

I've now added a simple harness to test these instructions.  It works by 
jumping into big real mode, forcing kvm to emulate (if 
emulate_invalid_guest_state=1) and returning.

Please review it as well as the few fixes I've made in kvm to support 
it.  It's in the 'realmode' branch of both kvm.git and 
kvm-userspace.git.  Once it passes regression testing, I'll merge it 
into master.

-- 
error compiling committee.c: too many arguments to function

Re: [PATCH][RESEND] x86 emulator: Add in/out instructions (opcodes 0xe4-0xe7, 0xec-0xef)

[Avi Kivity]

Avi Kivity wrote:
>> To be clear, do you want an emulator test case (in
>> user/test/x86/emulator.c) for every instruction added to the emulator?
>>   
>
> Yes.  We've been bitten by rarely-used instructions being broken.
>
> I've now added a simple harness to test these instructions.  It works 
> by jumping into big real mode, forcing kvm to emulate (if 
> emulate_invalid_guest_state=1) and returning.
>
> Please review it as well as the few fixes I've made in kvm to support 
> it.  It's in the 'realmode' branch of both kvm.git and 
> kvm-userspace.git.  Once it passes regression testing, I'll merge it 
> into master.
>

The harness is in a new file, user/test/x86/realmode.c, btw.  emulate.c 
will be used for 64-bit instructions.

-- 
error compiling committee.c: too many arguments to function