Re: [Qemu-devel] [Qemu-trivial] [PATCH] qemu-char: Do not disconnect when there's data for reading

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Sep 24, 2014 at 11:52:37AM +0400, Michael Tokarev wrote:
> 16.09.2014 09:31, Zifei Tong wrote:
> > Friendly ping.
> > 
> > Also CC to qemu-trivial.
> 
> There was at least 2 subsequent versions of this down the line,
> a v2 and a v3.  (Just to show why I haven't applied it to -trivial).
> 
> Thanks,
> 
> /mjt

It's also far from trivial.
I don't see why it applies there.

> > On Sun, Sep 7, 2014 at 8:24 PM, Zifei Tong <zifeitong@gmail.com> wrote:
> >> After commit 812c1057f6175ac9a9829fa2920a2b5783814193 (Handle G_IO_HUP
> >> in tcp_chr_read for tcp chardev), the connection is disconnected when in
> >> G_IO_HUP condition.
> >>
> >> However, it's possible that the channel is in G_IO_IN condition at the
> >> same time, meaning there is data for reading. In that case, the
> >> remaining data is not handled.
> >>
> >> I saw a related bug when running socat in write-only mode, with
> >>
> >>   $ echo "quit" | socat -u - UNIX-CONNECT:qemu-monitor
> >>
> >> the monitor won't not run the 'quit' command.
> >>
> >> CC: Kirill Batuzov <batuzovk@ispras.ru>
> >> CC: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
> >> CC: Anthony Liguori <aliguori@amazon.com>
> >> Signed-off-by: Zifei Tong <zifeitong@gmail.com>
> >> ---
> >>  qemu-char.c | 2 +-
> >>  1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/qemu-char.c b/qemu-char.c
> >> index 1a8d9aa..5018c3a 100644
> >> --- a/qemu-char.c
> >> +++ b/qemu-char.c
> >> @@ -2706,7 +2706,7 @@ static gboolean tcp_chr_read(GIOChannel *chan, GIOCondition cond, void *opaque)
> >>      uint8_t buf[READ_BUF_LEN];
> >>      int len, size;
> >>
> >> -    if (cond & G_IO_HUP) {
> >> +    if (!(cond & G_IO_IN) && (cond & G_IO_HUP)) {
> >>          /* connection closed */
> >>          tcp_chr_disconnect(chr);
> >>          return TRUE;
> >> --
> >> 2.1.0
> >>
> > 
>