The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x 9d5eff7821f6d70f7d1b4d8a60680fba4de868a7 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2025081845-cork-enable-a1e8@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 9d5eff7821f6d70f7d1b4d8a60680fba4de868a7 Mon Sep 17 00:00:00 2001 From: Shyam Prasad N sprasad@microsoft.com Date: Thu, 17 Jul 2025 17:36:13 +0530 Subject: [PATCH] cifs: reset iface weights when we cannot find a candidate
We now do a weighted selection of server interfaces when allocating new channels. The weights are decided based on the speed advertised. The fulfilled weight for an interface is a counter that is used to track the interface selection. It should be reset back to zero once all interfaces fulfilling their weight.
In cifs_chan_update_iface, this reset logic was missing. As a result when the server interface list changes, the client may not be able to find a new candidate for other channels after all interfaces have been fulfilled.
Fixes: a6d8fb54a515 ("cifs: distribute channels across interfaces based on speed") Cc: stable@vger.kernel.org Signed-off-by: Shyam Prasad N sprasad@microsoft.com Signed-off-by: Steve French stfrench@microsoft.com
diff --git a/fs/smb/client/sess.c b/fs/smb/client/sess.c index 330bc3d25bad..0a8c2fcc9ded 100644 --- a/fs/smb/client/sess.c +++ b/fs/smb/client/sess.c @@ -332,6 +332,7 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server) struct cifs_server_iface *old_iface = NULL; struct cifs_server_iface *last_iface = NULL; struct sockaddr_storage ss; + int retry = 0;
spin_lock(&ses->chan_lock); chan_index = cifs_ses_get_chan_index(ses, server); @@ -360,6 +361,7 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server) return; }
+try_again: last_iface = list_last_entry(&ses->iface_list, struct cifs_server_iface, iface_head); iface_min_speed = last_iface->speed; @@ -397,6 +399,13 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server) }
if (list_entry_is_head(iface, &ses->iface_list, iface_head)) { + list_for_each_entry(iface, &ses->iface_list, iface_head) + iface->weight_fulfilled = 0; + + /* see if it can be satisfied in second attempt */ + if (!retry++) + goto try_again; + iface = NULL; cifs_dbg(FYI, "unable to find a suitable iface\n"); }