Kafs 6.16.0-rc3 BUG: kernel NULL pointer dereference

[markus.suvanto at gmail.com]

ke, 2025-08-13 kello 14:57 +0100, David Howells kirjoitti:
> markus.suvanto at gmail.com wrote:
> 
> > One more Ooops.
> > dmesg and /sys/kernel/tracing/trace below.
> 
> Did you have any test patches applied?
> 
> David

At least I hope so...
Kernel version was: 6.16.0-00001-g06057fe3ba40  
Git apply your patch from email to top of 6.16




commit 06057fe3ba40ba77b69781f239209c917036d898 (HEAD -> debug)
Author: David Howells <dhowells at redhat.com>
Date:   Tue Jul 8 15:59:31 2025 +0100

    Kafs 6.16.0-rc3 BUG: kernel NULL pointer dereference
    
    Hi Markus,
    
    Can you try applying the attached patch?  It just adds another couple of
    tracepoints.  And then turn on these on along with the previous:
    
    echo 1 > /sys/kernel/debug/tracing/events/afs/afs_new_server/enable
    echo 1 > /sys/kernel/debug/tracing/events/afs/afs_del_server/enable
    echo 1 > /sys/kernel/debug/tracing/events/afs/afs_cm_no_server/enable
    echo 1 > /sys/kernel/debug/tracing/events/afs/afs_cm_no_server_u/enable
    echo 1 > /sys/kernel/debug/tracing/events/error_report/enable
    
    What I'm trying to find out is if a server record is getting used after being
    freed.  We might also need to turn on:
    
    echo 1 > /sys/kernel/debug/tracing/events/afs/afs_server/enable
    
    but that produces a lot more output.
    
    David

commit 038d61fd642278bab63ee8ef722c50d10ab01e8f (tag: v6.16, origin/master, origin/HEAD, master)
Author: Linus Torvalds <torvalds at linux-foundation.org>
Date:   Sun Jul 27 14:26:38 2025 -0700

    Linux 6.16



-Markus