[Qemu-devel] Re: [PATCH v2] update bochs vbe interface

[Juan Quintela <quintela@redhat.com>]

Gerd Hoffmann <kraxel@redhat.com> wrote:
> The bochs vbe interface got a new register a while back, which specifies
> the linear framebuffer size in 64k units.  This patch adds support for
> the new register to qemu.  With this patch applied vgabios 0.6c works
> with qemu.
>
> [ v2:  Don't savevm the new register.  Doing so breaks migration,
>        and as it carries read-only information for the guest there
>        is no need to save it. ]


It don't compile (as expected).  VMSTATE_UINT16_ARRAY() checks that you
sent the whole array.


/mnt/kvm/qemu/qemu-negotiate/hw/vga.c:2219: error: invalid operands to binary - (have ‘uint16_t (*)[10]’ and ‘uint16_t (*)[11]’)
make[1]: *** [vga.o] Error 1
make[1]: *** Waiting for unfinished jobs....
^Cmake[1]: *** [translate.o] Interrupt
make[1]: *** [op_helper.o] Interrupt
make: *** [subdir-x86_64-softmmu] Interrupt

> ---
>  hw/vga.c     |    5 +++--
>  hw/vga_int.h |    6 +++++-
>  2 files changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/hw/vga.c b/hw/vga.c
> index 6a1a059..f9e07cf 100644
> --- a/hw/vga.c
> +++ b/hw/vga.c
> @@ -1955,7 +1955,8 @@ void vga_common_reset(VGACommonState *s)
>  #ifdef CONFIG_BOCHS_VBE
>      s->vbe_index = 0;
>      memset(s->vbe_regs, '\0', sizeof(s->vbe_regs));
> -    s->vbe_regs[VBE_DISPI_INDEX_ID] = VBE_DISPI_ID0;
> +    s->vbe_regs[VBE_DISPI_INDEX_ID] = VBE_DISPI_ID5;

Now, to show my ignorance, what does this change means?

I can't understand it looking at the whole file (but I don't understand
vga.c too well anyways).

Later, Juan.