Re: [Qemu-devel] [PATCH 24/26] acpi, acpi_piix: factor out GPE logic

[Avi Kivity <avi@redhat.com>]

On 04/18/2011 10:47 AM, Isaku Yamahata wrote:
> Hmm but it seems that there is another issue.
> With the previous patch, I confirmed sts and en are saved as expected.
>
> The related VMStateDescription are defined in acpi_piix.c in
> the following order.
> vmstate_acpi calls vmstate_gpe. and&vmstate_gpe<  &vmstate_acpi.
>

(gdb) p &vmstate_gpe
$1 = (const VMStateDescription *) 0x6f0b00
(gdb) p &vmstate_acpi
$2 = (const VMStateDescription *) 0x6f0aa0

So no.

> However, your call trace shows something different.
> (I'm assuming the stack trace is correct. gdb or compiler optimization?)
>
> static const VMStateDescription vmstate_gpe = {
> ...
>
> static const VMStateDescription vmstate_acpi = {
>      .fields      = (VMStateField []) {
> ...
>          VMSTATE_STRUCT(gpe, PIIX4PMState, 2, vmstate_gpe, ACPIGPE),
>
>
> >
> >  #0  0x000000000049aff4 in qemu_put_be16s (f=0x2427490, pv=0x1ae7580,
> >  size=2) at hw/hw.h:108
> >  #1  put_uint16 (f=0x2427490, pv=0x1ae7580, size=2) at savevm.c:855
> >  #2  0x000000000049c3e4 in vmstate_save_state (f=0x2427490,
> >  vmsd=0x6f0b00, opaque=0x21f5ef0) at savevm.c:1436
>
> vmsd = 0x6f0b00 =&vmstate_gpe<<<<<<  correct???

Correct.

> opaque = 0x21f5ef0 =&PIIX4PMState->gpe
>
> >  #3  0x000000000049c3b6 in vmstate_save_state (f=0x2427490,
> >  vmsd=0x6f0aa0, opaque=0x21f5b90) at savevm.c:1434
>
> vmsd = 0x6f0aa0 =&vmstate_acpi<<<<<<<<<<<<<  correct?

Correct.

> opaque = 0x21f5b90 =&PIIX4PMState
>
> opaque seems correct as
> 0x21f5b90 - 0x21f5ef0 = 0x348 = offsetof(PIIX4PMState, gpe)
>
>
> On my environment the stack trace looks like
> (gdb) where
> #0  vmstate_save_state (f=0x25d16d0, vmsd=0x695940, opaque=0x283a218)
>      at savevm.c:1374
> #1  0x00000000004bb4f7 in vmstate_save_state (f=0x25d16d0, vmsd=0x695a40,
>      opaque=0x2839ed0) at savevm.c:1412
> ...
>
> (gdb) print&vmstate_gpe
> $32 = (const VMStateDescription *) 0x695940
> (gdb) print&vmstate_acpi
> $33 = (const VMStateDescription *) 0x695a40
>

Are you using qemu-kvm.git or qemu.git?  I think there are indeed two 
issues, your patch fixes the first and there is another that is specific 
to qemu-kvm.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.