On Thu, Nov 9, 2023 at 6:58 PM Paulo Alcantara <pc@xxxxxxxxxxxxx> wrote: > > Shyam Prasad N <nspmangalore@xxxxxxxxx> writes: > > > On Thu, Nov 9, 2023 at 1:11 AM Paulo Alcantara <pc@xxxxxxxxxxxxx> wrote: > >> > >> > and leaked server connections > >> > > >> > Display Internal CIFS Data Structures for Debugging > >> > --------------------------------------------------- > >> > CIFS Version 2.46 > >> > Features: DFS,FSCACHE,STATS2,DEBUG2,ALLOW_INSECURE_LEGACY,CIFS_POSIX,UPCALL(SPNEGO),XATTR,ACL,WITNESS > >> > CIFSMaxBufSize: 16384 > >> > Active VFS Requests: 0 > >> > > >> > Servers: > >> > 1) ConnectionId: 0x70e Hostname: w22-root2.gandalf.test > >> > ClientGUID: 44DAE383-3E91-3042-85FE-87D6F17298B7 > >> > Number of credits: 1,1,1 Dialect 0x210 > >> > Server capabilities: 0x300007 > >> > TCP status: 4 Instance: 77 > >> > Local Users To Server: 1 SecMode: 0x1 Req On Wire: 0 Net namespace: 4026531840 > >> > In Send: 0 In MaxReq Wait: 0 > >> > DFS leaf full path: \\W22-ROOT1.GANDALF.TEST\dfstest3\link10 > >> > > >> > Sessions: > >> > [NONE] > >> > 2) ConnectionId: 0x706 Hostname: w22-root2.gandalf.test > >> > ClientGUID: C8CF45E4-F70D-DF40-8821-0234A2E20DD4 > >> > Number of credits: 1,1,1 Dialect 0x210 > >> > Server capabilities: 0x300007 > >> > TCP status: 4 Instance: 81 > >> > Local Users To Server: 1 SecMode: 0x1 Req On Wire: 0 Net namespace: 4026531840 > >> > In Send: 0 In MaxReq Wait: 0 > >> > DFS leaf full path: \\W22-ROOT1.GANDALF.TEST\dfstest3\link6 > >> > > >> > Sessions: > >> > [NONE] > >> > 3) ConnectionId: 0x6ae Hostname: w22-root1.gandalf.test > >> > ClientGUID: AB059CDD-12FF-B94D-B30C-9E1928ACBA95 > >> > Number of credits: 1,1,1 Dialect 0x210 > >> > Server capabilities: 0x300007 > >> > TCP status: 4 Instance: 96 > >> > Local Users To Server: 1 SecMode: 0x1 Req On Wire: 0 Net namespace: 4026531840 > >> > In Send: 0 In MaxReq Wait: 0 > >> > DFS leaf full path: \\W22-ROOT1.GANDALF.TEST\dfstest3\link9 > >> > > >> > Sessions: > >> > [NONE] > >> > ... > >> > >> I ended up with a simple reproducer for the above > >> > >> mount.cifs //srv/share /mnt/1 -o ...,echo_interval=10 > >> iptables -I INPUT -s $srvaddr -j DROP > >> stat -f /mnt/1 > >> # check dmesg for "BUG: sleeping function called from invalid context" > >> iptables -I INPUT -s $srvaddr -j ACCEPT > >> stat -f /mnt/1 > >> umount /mnt/1 > >> # check /proc/fs/cifs/DebugData for leaked server connection > > > > Ack. I'll try and get a repro locally and debug this one. > > This should be related to patch 10/14 as you're taking an extra > reference of @server over reconnect, and when the client reconnects and > umount, that reference don't seem to be put afterwards. The idea is that the reference is put in the reconnect worker. I think the issue is that I don't drop the final reference if cancel_delayed_work_sync was able to cancel a work. Let me work on the updated patch. Also, I found the reason for "BUG: sleeping function called from invalid context". I've enabled CONFIG_DEBUG_ATOMIC_SLEEP in my test config now. -- Regards, Shyam
