Re: kern/46221: Kernel panic in NFS server code

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

The following reply was made to PR kern/46221; it has been noted by GNATS.

From: Manuel Bouyer <bouyer%antioche.eu.org@localhost>
To: Matthias Scheler <tron%zhadum.org.uk@localhost>
Cc: NetBSD GNATS <gnats-bugs%NetBSD.org@localhost>
Subject: Re: kern/46221: Kernel panic in NFS server code
Date: Sun, 18 Mar 2012 19:16:28 +0100

 On Sun, Mar 18, 2012 at 05:44:41PM +0000, Matthias Scheler wrote:
 > 
 > > It would be interesting to see where ffs_fhtovp+0x55 points to in sources.
 > 
 > If you pleae tell me how to find that out in gdb(?) I will happily provide
 > the information. Alternatively you can find the kernel image here:
 > 
 >      http://files.zhadum.org.uk/netbsd.gdb.xz
 
 (gdb) l *(ffs_fhtovp+0x55)
 0xffffffff801af684 is in ffs_fhtovp (/usr/src/sys/ufs/ffs/ffs_vfsops.c:1907).
 1902    /usr/src/sys/ufs/ffs/ffs_vfsops.c: No such file or directory.
         in /usr/src/sys/ufs/ffs/ffs_vfsops.c
 
 But this is at the very end of ffs_fhtovp(). I don't know if ddb is somewhat
 confused when computing the stack trace, or something else.
 
 (gdb) x/i ffs_fhtovp+0x55
    0xffffffff801af684 <ffs_fhtovp+85>:  leaveq 
 (gdb) disas ffs_fhtovp
 [...]
    0xffffffff801af67f <+80>:    callq  0xffffffff8042b0f3 <ufs_fhtovp>
    0xffffffff801af684 <+85>:    leaveq 
    0xffffffff801af685 <+86>:    retq   
 
 Either ddb skipped the call to ufs_fhtovp (and so the place where it
 crashed in ufs_fhtovp) or the stack is corrupted.
 The exact trap message from ddb and the register dump would be usefull.
 
 -- 
 Manuel Bouyer <bouyer%antioche.eu.org@localhost>
      NetBSD: 26 ans d'experience feront toujours la difference
 --