On Thu, Nov 9, 2023 at 7:19 PM Shyam Prasad N <nspmangalore@gmail.com> wrote:
>
> On Thu, Nov 9, 2023 at 6:58 PM Paulo Alcantara <pc@manguebit.com> wrote:
> >
> > Shyam Prasad N <nspmangalore@gmail.com> writes:
> >
> > > On Thu, Nov 9, 2023 at 1:11 AM Paulo Alcantara <pc@manguebit.com> 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.
This was already taken care of.

> 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

Hi Paulo,

Can you please check if the problem is still seen with these updated patches?
I was unable to reproduce the issue with the steps you provided.

-- 
Regards,
Shyam