This is a note to let you know that I've just added the patch titled SUNRPC: Fix a server shutdown leak to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: sunrpc-fix-a-server-shutdown-leak.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 91d6554571f572d806bea65aa4ddd99ab6143df6 Author: Benjamin Coddington <bcodding@xxxxxxxxxx> Date: Fri Mar 3 16:08:32 2023 -0500 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@xxxxxxxxxx> Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index 08ca797bb8a46..74a1c9116a785 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -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;