summaryrefslogtreecommitdiff
path: root/fs/nfs/callback_proc.c
diff options
context:
space:
mode:
authorTrond Myklebust <trondmy@gmail.com>2018-08-14 17:55:56 -0400
committerAnna Schumaker <Anna.Schumaker@Netapp.com>2018-08-15 12:05:15 -0400
commit8618289c46556fd4dd259a1af02ccc448032f48d (patch)
treedae02612130410f169459c9a56e81dcbab2e7f6b /fs/nfs/callback_proc.c
parentd0fbb1d8a194c0ec0180c1d073ad709e45503a43 (diff)
NFSv4: Fix a sleep in atomic context in nfs4_callback_sequence()
We must drop the lock before we can sleep in referring_call_exists(). Reported-by: Jia-Ju Bai <baijiaju1990@gmail.com> Fixes: 045d2a6d076a ("NFSv4.1: Delay callback processing...") Cc: stable@vger.kernel.org # v4.9+ Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Diffstat (limited to 'fs/nfs/callback_proc.c')
-rw-r--r--fs/nfs/callback_proc.c14
1 files changed, 10 insertions, 4 deletions
diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index cd733649646b..fa515d5ea5ba 100644
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -442,11 +442,14 @@ validate_seqid(const struct nfs4_slot_table *tbl, const struct nfs4_slot *slot,
* a match. If the slot is in use and the sequence numbers match, the
* client is still waiting for a response to the original request.
*/
-static bool referring_call_exists(struct nfs_client *clp,
+static int referring_call_exists(struct nfs_client *clp,
uint32_t nrclists,
- struct referring_call_list *rclists)
+ struct referring_call_list *rclists,
+ spinlock_t *lock)
+ __releases(lock)
+ __acquires(lock)
{
- bool status = false;
+ int status = 0;
int i, j;
struct nfs4_session *session;
struct nfs4_slot_table *tbl;
@@ -469,8 +472,10 @@ static bool referring_call_exists(struct nfs_client *clp,
for (j = 0; j < rclist->rcl_nrefcalls; j++) {
ref = &rclist->rcl_refcalls[j];
+ spin_unlock(lock);
status = nfs4_slot_wait_on_seqid(tbl, ref->rc_slotid,
ref->rc_sequenceid, HZ >> 1) < 0;
+ spin_lock(lock);
if (status)
goto out;
}
@@ -547,7 +552,8 @@ __be32 nfs4_callback_sequence(void *argp, void *resp,
* related callback was received before the response to the original
* call.
*/
- if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists)) {
+ if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists,
+ &tbl->slot_tbl_lock) < 0) {
status = htonl(NFS4ERR_DELAY);
goto out_unlock;
}