NLM: don't let lockd exit on unexpected svc_recv errors (try #2)

When svc_recv returns an unexpected error, lockd will print a warning
and exit. This problematic for several reasons. In particular, it will
cause the reference counts for the thread to be wrong, and can lead to a
potential BUG() call.

Rather than exiting on error from svc_recv, have the thread do a 1s
sleep and then retry the loop. This is unlikely to cause any harm, and
if the error turns out to be something temporary then it may be able to
recover.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This commit is contained in:
Jeff Layton 2008-04-08 15:40:08 -04:00 committed by J. Bruce Fields
parent 06e02d66fa
commit f97c650dda

View File

@ -112,7 +112,7 @@ static inline void clear_grace_period(void)
static int
lockd(void *vrqstp)
{
int err = 0;
int err = 0, preverr = 0;
struct svc_rqst *rqstp = vrqstp;
unsigned long grace_period_expire;
@ -172,14 +172,20 @@ lockd(void *vrqstp)
* recvfrom routine.
*/
err = svc_recv(rqstp, timeout);
if (err == -EAGAIN || err == -EINTR)
if (err == -EAGAIN || err == -EINTR) {
preverr = err;
continue;
if (err < 0) {
printk(KERN_WARNING
"lockd: terminating on error %d\n",
-err);
break;
}
if (err < 0) {
if (err != preverr) {
printk(KERN_WARNING "%s: unexpected error "
"from svc_recv (%d)\n", __func__, err);
preverr = err;
}
schedule_timeout_interruptible(HZ);
continue;
}
preverr = err;
dprintk("lockd: request from %s\n",
svc_print_addr(rqstp, buf, sizeof(buf)));