This is a note to let you know that I've just added the patch titled Revert "cifs: reconnect work should have reference on server struct" to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: revert-cifs-reconnect-work-should-have-reference-on-.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 8ac376c7b23cd48dc254ca7f1710bfb1727c4d53 Author: Shyam Prasad N <sprasad@xxxxxxxxxxxxx> Date: Wed Dec 6 16:37:37 2023 +0000 Revert "cifs: reconnect work should have reference on server struct" [ Upstream commit 823342524868168bf681f135d01b4ae10f5863ec ] This reverts commit 19a4b9d6c372cab6a3b2c9a061a236136fe95274. This earlier commit was making an assumption that each mod_delayed_work called for the reconnect work would result in smb2_reconnect_server being called twice. This assumption turns out to be untrue. So reverting this change for now. I will submit a follow-up patch to fix the actual problem in a different way. Signed-off-by: Shyam Prasad N <sprasad@xxxxxxxxxxxxx> Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx> Stable-dep-of: 78e727e58e54 ("cifs: update iface_last_update on each query-and-update") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c index f43f51f2d1c1..2a30245287d5 100644 --- a/fs/smb/client/connect.c +++ b/fs/smb/client/connect.c @@ -401,13 +401,7 @@ static int __cifs_reconnect(struct TCP_Server_Info *server, spin_unlock(&server->srv_lock); cifs_swn_reset_server_dstaddr(server); cifs_server_unlock(server); - - /* increase ref count which reconnect work will drop */ - spin_lock(&cifs_tcp_ses_lock); - server->srv_count++; - spin_unlock(&cifs_tcp_ses_lock); - if (mod_delayed_work(cifsiod_wq, &server->reconnect, 0)) - cifs_put_tcp_session(server, false); + mod_delayed_work(cifsiod_wq, &server->reconnect, 0); } } while (server->tcpStatus == CifsNeedReconnect); @@ -537,13 +531,7 @@ static int reconnect_dfs_server(struct TCP_Server_Info *server) spin_unlock(&server->srv_lock); cifs_swn_reset_server_dstaddr(server); cifs_server_unlock(server); - - /* increase ref count which reconnect work will drop */ - spin_lock(&cifs_tcp_ses_lock); - server->srv_count++; - spin_unlock(&cifs_tcp_ses_lock); - if (mod_delayed_work(cifsiod_wq, &server->reconnect, 0)) - cifs_put_tcp_session(server, false); + mod_delayed_work(cifsiod_wq, &server->reconnect, 0); } while (server->tcpStatus == CifsNeedReconnect); mutex_lock(&server->refpath_lock); @@ -1630,19 +1618,16 @@ cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect) cancel_delayed_work_sync(&server->echo); - if (from_reconnect) { + if (from_reconnect) /* * Avoid deadlock here: reconnect work calls * cifs_put_tcp_session() at its end. Need to be sure * that reconnect work does nothing with server pointer after * that step. */ - if (cancel_delayed_work(&server->reconnect)) - cifs_put_tcp_session(server, from_reconnect); - } else { - if (cancel_delayed_work_sync(&server->reconnect)) - cifs_put_tcp_session(server, from_reconnect); - } + cancel_delayed_work(&server->reconnect); + else + cancel_delayed_work_sync(&server->reconnect); spin_lock(&server->srv_lock); server->tcpStatus = CifsExiting; diff --git a/fs/smb/client/smb2pdu.c b/fs/smb/client/smb2pdu.c index f1977987ae74..da752f41a4e6 100644 --- a/fs/smb/client/smb2pdu.c +++ b/fs/smb/client/smb2pdu.c @@ -3981,6 +3981,12 @@ void smb2_reconnect_server(struct work_struct *work) } spin_unlock(&ses->chan_lock); } + /* + * Get the reference to server struct to be sure that the last call of + * cifs_put_tcon() in the loop below won't release the server pointer. + */ + if (tcon_exist || ses_exist) + server->srv_count++; spin_unlock(&cifs_tcp_ses_lock); @@ -4028,17 +4034,13 @@ void smb2_reconnect_server(struct work_struct *work) done: cifs_dbg(FYI, "Reconnecting tcons and channels finished\n"); - if (resched) { + if (resched) queue_delayed_work(cifsiod_wq, &server->reconnect, 2 * HZ); - mutex_unlock(&pserver->reconnect_mutex); - - /* no need to put tcp session as we're retrying */ - return; - } mutex_unlock(&pserver->reconnect_mutex); /* now we can safely release srv struct */ - cifs_put_tcp_session(server, true); + if (tcon_exist || ses_exist) + cifs_put_tcp_session(server, 1); } int @@ -4058,12 +4060,7 @@ SMB2_echo(struct TCP_Server_Info *server) server->ops->need_neg(server)) { spin_unlock(&server->srv_lock); /* No need to send echo on newly established connections */ - spin_lock(&cifs_tcp_ses_lock); - server->srv_count++; - spin_unlock(&cifs_tcp_ses_lock); - if (mod_delayed_work(cifsiod_wq, &server->reconnect, 0)) - cifs_put_tcp_session(server, false); - + mod_delayed_work(cifsiod_wq, &server->reconnect, 0); return rc; } spin_unlock(&server->srv_lock);