On Sat, Jul 22, 2017 at 09:24:27AM +0000, Marc-André Lureau wrote:
>
>
> On Sat, Jul 22, 2017 at 2:35 AM Michael S. Tsirkin <m...@redhat.com> wrote:
>
> On Fri, Jul 21, 2017 at 11:19:04AM +0000, Marc-André Lureau wrote:
> > Hi
> >
> > On Fri, Jul 21, 2017 at 7:18 AM w00273186 <wangyunj...@huawei.com>
> wrote:
> >
> > From: Yunjian Wang <wangyunj...@huawei.com>
> >
> > "nc" is freed after hotplug vhost-user, but the watcher don't be
> removed.
> > The QEMU crash when the watcher access the "nc" on socket
> disconnect.
> >
> >
> >
> > This is actually your 3rd iteration on the patch
> >
> > Could your describe your changes since:
> > "[PATCH v2] vhost-user: fix watcher need be removed when vhost-user
> hotplug"
> >
> > Thanks
>
> Yes but it's a 3-liner. That's way below the limit where you need
> detailed change history. Does the patch make sense to you?
>
>
>
> That's not all, the fact that he didn't come up with the same solution in the
> first place, and I didn't notice a problem either with the previous approach
> is
> enough to ask from some clarification on which approach is best, and I bet
> there is something to say.
I'm rather confused. Looks like you were the one who asked for the change.
Really we want to attract new contributors and a small bugfix like this
seems like a very good way to start contributing. Changelog is already
3 times the size of the patch here. So I think we should just get the patch
reviewed and applied if correct. Do you plan to review it?
> Furthermore, we would really benefit from having repeatable cases for this
> kind
> of fixes.
I agree disconnect path is but tested adequately but I don't think we
are at a point where we should be asking for testcases for every use
after free bug that gets fixed.
>
>
> >
> > Program received signal SIGSEGV, Segmentation fault.
> > #0 object_get_class (obj=obj@entry=0x2) at qom/object.c:750
> > #1 0x00007f9bb4180da1 in qemu_chr_fe_disconnect (be=<optimized
> out>)
> > at chardev/char-fe.c:372
> > #2 0x00007f9bb40d1100 in net_vhost_user_watch (chan=<optimized
> out>,
> > cond=<optimized out>, opaque=<optimized out>) at
> net/vhost-user.c:188
> > #3 0x00007f9baf97f99a in g_main_context_dispatch () from /usr/
> lib64/
> > libglib-2.0.so.0
> > #4 0x00007f9bb41d7ebc in glib_pollfds_poll () at util/
> main-loop.c:213
> > #5 os_host_main_loop_wait (timeout=<optimized out>) at util/
> > main-loop.c:261
> > #6 main_loop_wait (nonblocking=nonblocking@entry=0) at util/
> > main-loop.c:515
> > #7 0x00007f9bb3e266a7 in main_loop () at vl.c:1917
> > #8 main (argc=<optimized out>, argv=<optimized out>, envp=
> <optimized
> > out>) at vl.c:4786
> >
> > Signed-off-by: Yunjian Wang <wangyunj...@huawei.com>
> > ---
> > net/vhost-user.c | 4 ++++
> > 1 file changed, 4 insertions(+)
> >
> > diff --git a/net/vhost-user.c b/net/vhost-user.c
> > index 36f32a2..c23927c 100644
> > --- a/net/vhost-user.c
> > +++ b/net/vhost-user.c
> > @@ -151,6 +151,10 @@ static void vhost_user_cleanup(NetClientState
> *nc)
> > s->vhost_net = NULL;
> > }
> > if (nc->queue_index == 0) {
> > + if (s->watch) {
> > + g_source_remove(s->watch);
> > + s->watch = 0;
> > + }
> > qemu_chr_fe_deinit(&s->chr, true);
> > }
> >
> > --
> > 1.8.3.1
> >
> >
> >
> >
> > --
> > Marc-André Lureau
>
> --
> Marc-André Lureau
Why do you even bother including the patch if you use a client that
corrupts both the patch and the commit log formatting? It's not a good
example to give to new contributors and it doesn't align well
with nit-picking about same commit log, in my eyes.
--
MST
