Re: [PATCH] qemu-nbd: set timeout to qemu-nbd socket

[Denis V. Lunev]

On 9/26/22 12:05, Vladimir Sementsov-Ogievskiy wrote:
> [+ Den]
>
> On 9/25/22 16:53, luzhipeng wrote:
> > From: lu zhipeng <luzhipeng@cestc.cn>
> >
> > Prevent the NBD socket stuck all the time, So
> > set timeout.
> >
> > Signed-off-by: lu zhipeng <luzhipeng@cestc.cn>
> > ---
> >   nbd/client.c | 8 ++++++++
> >   1 file changed, 8 insertions(+)
> >
> > diff --git a/nbd/client.c b/nbd/client.c
> > index 30d5383cb1..89dde53a0f 100644
> > --- a/nbd/client.c
> > +++ b/nbd/client.c
> > @@ -24,6 +24,8 @@
> >   #include "nbd-internal.h"
> >   #include "qemu/cutils.h"
> >   +#define NBD_DEFAULT_TIMEOUT 30
> > +
> >   /* Definitions for opaque data types */
> >     static QTAILQ_HEAD(, NBDExport) exports = 
> > QTAILQ_HEAD_INITIALIZER(exports);
> > @@ -1301,6 +1303,12 @@ int nbd_init(int fd, QIOChannelSocket *sioc, 
> > NBDExportInfo *info,
> >           }
> >       }
> >   +    if (ioctl(fd, NBD_SET_TIMEOUT, NBD_DEFAULT_TIMEOUT) < 0) {
> > +        int serrno = errno;
> > +        error_setg(errp, "Failed setting timeout");
> > +        return -serrno;
> > +    }
> > +
> >       trace_nbd_init_finish();
> >         return 0;
>
>
> Personally, I don't see a problem in enabling timeout by default.. But 
> probably we need a new option instead?
I believe that this should be the same story as we have had with
KEEPALIVE. This should be set as an option and downstream
will change its default when necessary.

Den