hvf and APIC fixes, improvements, and optimisations

[PATCH 09/11] i386/hvf: Print hex pairs for each opcode byte in decode error

Posted by phil@philjordan.eu 5 months ago

From: Phil Dennis-Jordan <phil@philjordan.eu>

Printing a sequence of bytes as hex with leading zeroes omitted just looks odd.

Signed-off-by: Phil Dennis-Jordan <phil@philjordan.eu>
---
 target/i386/hvf/x86_decode.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/i386/hvf/x86_decode.c b/target/i386/hvf/x86_decode.c
index 6c7cfc820f..f8d37f2d53 100644
--- a/target/i386/hvf/x86_decode.c
+++ b/target/i386/hvf/x86_decode.c
@@ -30,7 +30,7 @@ static void decode_invalid(CPUX86State *env, struct x86_decode *decode)
 {
     printf("%llx: failed to decode instruction ", env->eip);
     for (int i = 0; i < decode->opcode_len; i++) {
-        printf("%x ", decode->opcode[i]);
+        printf("%02x ", decode->opcode[i]);
     }
     printf("\n");
     VM_PANIC("decoder failed\n");
-- 
2.39.3 (Apple Git-146)

Re: [PATCH 09/11] i386/hvf: Print hex pairs for each opcode byte in decode error

Posted by Philippe Mathieu-Daudé 5 months ago

On 9/12/24 21:36, phil@philjordan.eu wrote:
> From: Phil Dennis-Jordan <phil@philjordan.eu>
> 
> Printing a sequence of bytes as hex with leading zeroes omitted just looks odd.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

> 
> Signed-off-by: Phil Dennis-Jordan <phil@philjordan.eu>
> ---
>   target/i386/hvf/x86_decode.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/target/i386/hvf/x86_decode.c b/target/i386/hvf/x86_decode.c
> index 6c7cfc820f..f8d37f2d53 100644
> --- a/target/i386/hvf/x86_decode.c
> +++ b/target/i386/hvf/x86_decode.c
> @@ -30,7 +30,7 @@ static void decode_invalid(CPUX86State *env, struct x86_decode *decode)
>   {
>       printf("%llx: failed to decode instruction ", env->eip);
>       for (int i = 0; i < decode->opcode_len; i++) {
> -        printf("%x ", decode->opcode[i]);
> +        printf("%02x ", decode->opcode[i]);
>       }
>       printf("\n");

Maybe we should use monitor_printf() here?

>       VM_PANIC("decoder failed\n");

Re: [PATCH 09/11] i386/hvf: Print hex pairs for each opcode byte in decode error

Posted by Phil Dennis-Jordan 5 months ago

On Mon, 9 Dec 2024 at 21:54, Philippe Mathieu-Daudé <philmd@linaro.org>
wrote:

> On 9/12/24 21:36, phil@philjordan.eu wrote:
> > From: Phil Dennis-Jordan <phil@philjordan.eu>
> >
> > Printing a sequence of bytes as hex with leading zeroes omitted just
> looks odd.
>
> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
>
> >
> > Signed-off-by: Phil Dennis-Jordan <phil@philjordan.eu>
> > ---
> >   target/i386/hvf/x86_decode.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/target/i386/hvf/x86_decode.c b/target/i386/hvf/x86_decode.c
> > index 6c7cfc820f..f8d37f2d53 100644
> > --- a/target/i386/hvf/x86_decode.c
> > +++ b/target/i386/hvf/x86_decode.c
> > @@ -30,7 +30,7 @@ static void decode_invalid(CPUX86State *env, struct
> x86_decode *decode)
> >   {
> >       printf("%llx: failed to decode instruction ", env->eip);
> >       for (int i = 0; i < decode->opcode_len; i++) {
> > -        printf("%x ", decode->opcode[i]);
> > +        printf("%02x ", decode->opcode[i]);
> >       }
> >       printf("\n");
>
> Maybe we should use monitor_printf() here?
>

Or perhaps snprintf it into a buffer, then change this…


> >       VM_PANIC("decoder failed\n");
>
>
… to a VM_PANIC_EX() that also writes out the opcode buffer?