Re: Panic in sys_fstatat()

On Thu, Feb 14, 2019 at 12:26:01PM -0800, John Baldwin wrote:
> On 2/13/19 6:47 PM, Steve Kargl wrote:
> > #16 0x00ff58bb in trap (frame=0x2e7b6880) at /usr/src/sys/i386/i386/trap.c:519
> > #17 0xffc0315d in ?? ()
> > #18 0x2e7b6880 in ?? ()
> > #19 0x00d1de64 in lookup (ndp=0x2e7b6a50)
> >     at /usr/src/sys/kern/vfs_lookup.c:710
> > #20 0x00d1d763 in namei (ndp=0x2e7b6a50) at /usr/src/sys/kern/vfs_lookup.c:487
> > #21 0x00d372c5 in kern_statat (td=0x3c5dc700, flag=0, fd=-100, 
> >     path=0x2cced08e <error: Cannot access memory at address 0x2cced08e>, 
> >     pathseg=UIO_USERSPACE, sbp=0x2e7b6b18, hook=0x0)
> >     at /usr/src/sys/kern/vfs_syscalls.c:2307
> > #22 0x00d37c99 in sys_fstatat (td=0x3c5dc700, uap=0x3c5dc988)
> >     at /usr/src/sys/kern/vfs_syscalls.c:2284
> > #23 0x00ff69fa in syscallenter (td=<optimized out>)
> >     at /usr/src/sys/i386/i386/../../kern/subr_syscall.c:135
> > #24 syscall (frame=0x2e7b6ce8) at /usr/src/sys/i386/i386/trap.c:1144
> > #25 0xffc033a7 in ?? ()
> > #26 0x2e7b6ce8 in ?? ()
> > Backtrace stopped: Cannot access memory at address 0xfbafbbbc
> > (kgdb) 
> 
> Frame 18 is probably the root problem, though it doesn't look like kgdb is
> able to unwind it correctly.  Looking at frame 19 might help though.  It
> seems like a NULL pointer dereference when invoking VOP_LOCK.
> 

I can't look at this until tonight (about 6-7 hours).
Anything in frame 19 that you would be particularly
interested in?

-- 
Steve