From: Benjamin Coddington bcodding@redhat.com
[ 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 --- net/sunrpc/svc.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index d38788cd9433a..af657a482ad2d 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -800,6 +800,7 @@ 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;
@@ -808,7 +809,10 @@ 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;