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

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.