Re: [Qemu-devel] [Qemu-block] Guest unresponsive after Virtqueue size exceeded error

[Stefan Hajnoczi <stefanha@gmail.com>]

On Mon, Feb 25, 2019 at 10:30 AM Stefan Hajnoczi <stefanha@gmail.com> wrote:
> On Sat, Feb 23, 2019 at 3:55 PM Natanael Copa <ncopa@alpinelinux.org> wrote:
> > On Fri, 22 Feb 2019 14:04:20 +0000
> > Stefan Hajnoczi <stefanha@gmail.com> wrote:
> > > On Fri, Feb 22, 2019 at 12:57 PM Fernando Casas Schössow
> > > <casasfernando@outlook.com> wrote:
> > I tried to find this section. How do you get the assembly listing of
> > relevant secion? I tried to do "disas virtio_pop" from
> > `gdb /usr/bin/qemu-system-x86_64` from the binary in alpine edge. I
> > could find 2 memcpy but none of them look like a 16 bit operation after:
> >
> >    0x00000000004551f1 <+353>:   mov    0x10(%rsp),%rdi
> >    0x00000000004551f6 <+358>:   mov    $0x10,%edx
> >    0x00000000004551fb <+363>:   callq  0x3879e0 <memcpy@plt>
> >    0x0000000000455200 <+368>:   movzwl 0x5c(%rsp),%eax
> >    0x0000000000455205 <+373>:   test   $0x4,%al
> >    0x0000000000455207 <+375>:   je     0x4552aa <virtqueue_pop+538>
> >
> > ....
> >
> >    0x0000000000455291 <+513>:   mov    0x10(%rsp),%rdi
> >    0x0000000000455296 <+518>:   mov    $0x10,%edx
> >    0x000000000045529b <+523>:   callq  0x3879e0 <memcpy@plt>
> >    0x00000000004552a0 <+528>:   mov    %rbp,0x20(%rsp)
> >    0x00000000004552a5 <+533>:   movzwl 0x5c(%rsp),%eax
> >    0x00000000004552aa <+538>:   lea    0x20e0(%rsp),%rdi
> >    0x00000000004552b2 <+546>:   xor    %r11d,%r11d
> >    0x00000000004552b5 <+549>:   mov    %r15,0x38(%rsp)
>
> Here is the beginning of the function:

This was built from the docker alpine image:
REPOSITORY          TAG                 IMAGE ID            CREATED
         SIZE
docker.io/alpine    latest              caf27325b298        3 weeks
ago         5.52 MB

aports git commit: be41538f0061b406a374564a0043a363efcb0293
gcc (Alpine 8.2.0) 8.2.0

Stefan