2021-03-04 14:01:08

by Benjamin Coddington

[permalink] [raw]
Subject: [PATCH] SUNRPC: Set memalloc_nofs_save() for sync tasks

We could recurse into NFS doing memory reclaim while sending a sync task,
which might result in a deadlock. Set memalloc_nofs_save for sync task
execution.

Fixes: a1231fda7e94 ("SUNRPC: Set memalloc_nofs_save() on all rpciod/xprtiod jobs")
Signed-off-by: Benjamin Coddington <[email protected]>
---
net/sunrpc/sched.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index cf702a5f7fe5..39ed0e0afe6d 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -963,8 +963,11 @@ void rpc_execute(struct rpc_task *task)

rpc_set_active(task);
rpc_make_runnable(rpciod_workqueue, task);
- if (!is_async)
+ if (!is_async) {
+ unsigned int pflags = memalloc_nofs_save();
__rpc_execute(task);
+ memalloc_nofs_restore(pflags);
+ }
}

static void rpc_async_schedule(struct work_struct *work)
--
2.29.2