Re: r269147: NULL mp in getnewvnode() via kern_proc_filedesc_out()

On 8/5/2014 10:56 PM, Bryan Drewery wrote:
> On 8/5/2014 10:19 PM, Konstantin Belousov wrote:
>> On Tue, Aug 05, 2014 at 09:47:57PM -0500, Bryan Drewery wrote:
>>> Has anyone else encountered this? Got it while running poudriere.
>>>
>>>> NULL mp in getnewvnode()
>>>> [...]
>>>> vn_fullpath1() at vn_fullpath1+0x19d/frame 0xfffffe1247d8e540
>>>> vn_fullpath() at vn_fullpath+0xc1/frame 0xfffffe1247d8e590
>>>> export_fd_to_sb() at export_fd_to_sb+0x489/frame 0xfffffe1247d8e7c0
>>>> kern_proc_filedesc_out() at kern_proc_filedesc_out+0x234/frame
>>>> 0xfffffe1247d8e840
>>>> sysctl_kern_proc_filedesc() at sysctl_kern_proc_filedesc+0x84/frame
>>>> 0xfffffe1247d8e900
>>>> sysctl_root_handler_locked() at
>>>> sysctl_root_handler_locked+0x68/frame 0xfffffe1247d8e940
>>>> sysctl_root() at sysctl_root+0x18e/frame 0xfffffe1247d8e990
>>>> userland_sysctl() at userland_sysctl+0x192/frame 0xfffffe1247d8ea30
>>>> sys___sysctl() at sys___sysctl+0x74/frame 0xfffffe1247d8eae0
>>>> amd64_syscall() at amd64_syscall+0x25a/frame 0xfffffe1247d8ebf0
>>>> Xfast_syscall() at Xfast_syscall+0xfb/frame 0xfffffe1247d8ebf0
>>>
>>> Unfortunately I have no dump as the kmem was too large compared to my
>>> swap, and I didn't get to the console before some of the text was
>>> overwritten. Perhaps it will hit it again soon after reboot and I'll get
>>> a core.
>>
>> "NULL mp in getnewvnode()" is only the printf(), it is not a panic or
>> KASSERT.  The event does not stop the machine, nor it prints the
>> backtrace.
>>
>> You mentioned that you was unable to dump, so did the system paniced ?
>> Without full log of the panic messages and backtrace, it is impossible
>> to start guessing what the problem is.
>>
>> That said, the printf seemingly outlived its usefulness.
>>
> 
> Got it. I've set debug.debugger_on_panic=1 to not auto reboot on panic
> next time this happens. I had it at 0 which was causing the lack of
> information in these.

Here is the full trace:


> NULL mp in getnewvnode()
> VNASSERT failed
> 0xfffff806071dc760: tag null, type VDIR
>     usecount 1, writecount 0, refcount 1 mountedhere 0
>     flags ()
>     lock type zfs: EXCL by thread 0xfffff8009a53f490 (pid 1028, tmux, tid 100881)
>         vp=0xfffff806071dc760, lowervp=0xfffff8013157f588
> panic: Don't call insmntque(foo, NULL)
> cpuid = 5
> KDB: stack backtrace:
> db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe1247e76b50
> kdb_backtrace() at kdb_backtrace+0x39/frame 0xfffffe1247e76c00
> vpanic() at vpanic+0x126/frame 0xfffffe1247e76c40
> kassert_panic() at kassert_panic+0x139/frame 0xfffffe1247e76cb0
> insmntque1() at insmntque1+0x230/frame 0xfffffe1247e76cf0
> null_nodeget() at null_nodeget+0x158/frame 0xfffffe1247e76d60
> null_lookup() at null_lookup+0xeb/frame 0xfffffe1247e76dd0
> VOP_LOOKUP_APV() at VOP_LOOKUP_APV+0xf1/frame 0xfffffe1247e76e00
> lookup() at lookup+0x5ad/frame 0xfffffe1247e76e90
> namei() at namei+0x4e4/frame 0xfffffe1247e76f50
> vn_open_cred() at vn_open_cred+0x27a/frame 0xfffffe1247e770a0
> vop_stdvptocnp() at vop_stdvptocnp+0x161/frame 0xfffffe1247e773e0
> null_vptocnp() at null_vptocnp+0x2b/frame 0xfffffe1247e77440
> VOP_VPTOCNP_APV() at VOP_VPTOCNP_APV+0xf7/frame 0xfffffe1247e77470
> vn_vptocnp_locked() at vn_vptocnp_locked+0x118/frame 0xfffffe1247e774e0
> vn_fullpath1() at vn_fullpath1+0x19d/frame 0xfffffe1247e77540
> vn_fullpath() at vn_fullpath+0xc1/frame 0xfffffe1247e77590
> export_fd_to_sb() at export_fd_to_sb+0x489/frame 0xfffffe1247e777c0
> kern_proc_filedesc_out() at kern_proc_filedesc_out+0x234/frame 0xfffffe1247e77840
> sysctl_kern_proc_filedesc() at sysctl_kern_proc_filedesc+0x84/frame 0xfffffe1247e77900
> sysctl_root_handler_locked() at sysctl_root_handler_locked+0x68/frame 0xfffffe1247e77940
> sysctl_root() at sysctl_root+0x18e/frame 0xfffffe1247e77990
> userland_sysctl() at userland_sysctl+0x192/frame 0xfffffe1247e77a30
> sys___sysctl() at sys___sysctl+0x74/frame 0xfffffe1247e77ae0
> amd64_syscall() at amd64_syscall+0x25a/frame 0xfffffe1247e77bf0
> Xfast_syscall() at Xfast_syscall+0xfb/frame 0xfffffe1247e77bf0
> --- syscall (202, FreeBSD ELF64, sys___sysctl), rip = 0x801041fca, rsp = 0x7fffffffd878, rbp = 0x7fffffffd8b0 ---
> KDB: enter: panic
> [ thread pid 1028 tid 100881 ]
> Stopped at      kdb_enter+0x3e: movq    $0,kdb_why
> db> call doadump()
> 
> Dump failed. Partition too small.
> = 0



-- 
Regards,
Bryan Drewery