We can not hold the GlobalMid_Lock spinlock during the dfs processing in cifs_reconnect since it invokes things that may sleep and thus trigger :
BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:23
Thus we need to drop the spinlock during this code block.
RHBZ: 1716743
Cc: stable@vger.kernel.org Signed-off-by: Ronnie Sahlberg lsahlber@redhat.com --- fs/cifs/connect.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 8c4121da624e..8dd6637a3cbb 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -476,6 +476,7 @@ cifs_reconnect(struct TCP_Server_Info *server) spin_lock(&GlobalMid_Lock); server->nr_targets = 1; #ifdef CONFIG_CIFS_DFS_UPCALL + spin_unlock(&GlobalMid_Lock); cifs_sb = find_super_by_tcp(server); if (IS_ERR(cifs_sb)) { rc = PTR_ERR(cifs_sb); @@ -493,6 +494,7 @@ cifs_reconnect(struct TCP_Server_Info *server) } cifs_dbg(FYI, "%s: will retry %d target(s)\n", __func__, server->nr_targets); + spin_lock(&GlobalMid_Lock); #endif if (server->tcpStatus == CifsExiting) { /* the demux thread will exit normally