Re: [PATCH] Fix a typo that can cause slow socket response on Windows.

[Daniel P . Berrangé]

On Fri, Jan 29, 2021 at 02:31:49PM +0000, Hafiz Abid Qadeer wrote:
> We observed slow responses on a host forwarded port on Windows. Investigation 
> revealed that qemu_fd_register was being called with fd=-1 and this caused 
> g_poll in qemu_poll_ns timing out. I tracked this behavior to following 
> commit:
> 748f8f4 slirp: replace qemu_set_nonblock()
> 
> @@ -482,7 +483,8 @@ void tcp_connect(struct socket *inso)
>          tcp_close(sototcpcb(so)); /* This will sofree() as well */
>          return;
>      }
> -    qemu_set_nonblock(s);
> +    slirp_set_nonblock(s);
> +    so->slirp->cb->register_poll_fd(so->s);
> 
> It seems that calling register_poll_fd with so->s instead of s may be a typo. 
> Changing it back to s solves this issue. The commit 748f8f4 made similar 
> change in tcp_fconnect but I have not touched it.
> 
> Signed-off-by: Hafiz Abid Qadeer <abidh@codesourcery.com>
> ---
>  src/tcp_subr.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Thanks for your suggested patch, however, slirp is now spun off into its
own standalone project. You can submit patches using merge requests at

  https://gitlab.freedesktop.org/slirp/libslirp

QEMU will periodically pull in updates from slirp.

Regards,
Daniel
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