Commits
Stanislav Kinsbursky committed 384816051ca
SUNRPC: fix races on PipeFS MOUNT notifications Below are races, when RPC client can be created without PiepFS dentries CPU#0 CPU#1 ----------------------------- ----------------------------- rpc_new_client rpc_fill_super rpc_setup_pipedir mutex_lock(&sn->pipefs_sb_lock) rpc_get_sb_net == NULL (no per-net PipeFS superblock) sn->pipefs_sb = sb; notifier_call_chain(MOUNT) (client is not in the list) rpc_register_client (client without pipes dentries) To fix this patch: 1) makes PipeFS mount notification call with pipefs_sb_lock being held. 2) releases pipefs_sb_lock on new SUNRPC client creation only after registration. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>