SUNRPC: Fix a server shutdown leak

[ Upstream commit 9ca6705d9d609441d34f8b853e1e4a6369b3b171 ]

Fix a race where kthread_stop() may prevent the threadfn from ever getting
called.  If that happens the svc_rqst will not be cleaned up.

Fixes: ed6473ddc704 ("NFSv4: Fix callback server shutdown")
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Benjamin Coddington 2023-03-03 16:08:32 -05:00 committed by Greg Kroah-Hartman
parent 64d4eb4127
commit ad7e40ee15

View File

@ -806,6 +806,7 @@ EXPORT_SYMBOL_GPL(svc_set_num_threads);
static int
svc_stop_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
{
struct svc_rqst *rqstp;
struct task_struct *task;
unsigned int state = serv->sv_nrthreads-1;
@ -814,7 +815,10 @@ svc_stop_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
task = choose_victim(serv, pool, &state);
if (task == NULL)
break;
kthread_stop(task);
rqstp = kthread_data(task);
/* Did we lose a race to svo_function threadfn? */
if (kthread_stop(task) == -EINTR)
svc_exit_thread(rqstp);
nrservs++;
} while (nrservs < 0);
return 0;