From: Shyam Prasad N sprasad@microsoft.com
[ Upstream commit 88675b22d34e6e815ad4bde09c590ccb2d50c59d ]
In order to scale down the channels, the following sequence of operations happen: 1. server struct is marked for terminate 2. the channel is deallocated in the ses->chans array 3. at a later point the cifsd thread actually terminates the server
Between 2 and 3, there can be calls to find the channel for a server struct. When that happens, there can be an ugly warning that's logged. But this is expected.
So this change does two things: 1. in cifs_ses_get_chan_index, if server->terminate is set, return 2. always make sure server->terminate is set with chan_lock held
Signed-off-by: Shyam Prasad N sprasad@microsoft.com Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/smb/client/sess.c | 4 ++++ fs/smb/client/smb2pdu.c | 2 +- 2 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/fs/smb/client/sess.c b/fs/smb/client/sess.c index 2d3b332a79a1..b503a4833ae0 100644 --- a/fs/smb/client/sess.c +++ b/fs/smb/client/sess.c @@ -75,6 +75,10 @@ cifs_ses_get_chan_index(struct cifs_ses *ses, { unsigned int i;
+ /* if the channel is waiting for termination */ + if (server->terminate) + return CIFS_INVAL_CHAN_INDEX; + for (i = 0; i < ses->chan_count; i++) { if (ses->chans[i].server == server) return i; diff --git a/fs/smb/client/smb2pdu.c b/fs/smb/client/smb2pdu.c index ab8765113392..bd2822ad9b22 100644 --- a/fs/smb/client/smb2pdu.c +++ b/fs/smb/client/smb2pdu.c @@ -178,6 +178,7 @@ cifs_chan_skip_or_disable(struct cifs_ses *ses, }
ses->chans[chan_index].server = NULL; + server->terminate = true; spin_unlock(&ses->chan_lock);
/* @@ -188,7 +189,6 @@ cifs_chan_skip_or_disable(struct cifs_ses *ses, */ cifs_put_tcp_session(server, from_reconnect);
- server->terminate = true; cifs_signal_cifsd_for_reconnect(server, false);
/* mark primary server as needing reconnect */