Re: vdrain/cache trap panics on NetBSD/amd64-7.0_STABLE

[Greg Oster <oster%netbsd.org@localhost>]

On Wed, 5 Oct 2016 23:48:57 -0500 (CDT)
"John D. Baker" <jdbaker%mylinuxisp.com@localhost> wrote:

> Every so often, my file server panics and reboots--which it did
> just a few hours ago.  The saved core reports, via 'crash':
[snip]
> And the earliest I have saved (6 Nov 2015):
> 
> $ crash -N netbsd.2 -M netbsd.2.core 
> Crash version 7.0_STABLE, image version 7.0_STABLE.
> System panicked: trap
> Backtrace from time of crash is available.
> crash> bt  
> _KERNEL_OPT_NAGR() at 0
> _KERNEL_OPT_NAGR() at 0
> vpanic() at vpanic+0x145
> snprintf() at snprintf
> startlwp() at startlwp
> calltrap() at calltrap+0x11
> VOP_PUTPAGES() at VOP_PUTPAGES+0x3a
> uvm_pageout() at uvm_pageout+0x2f1
> 
> 
> Anyone else see anything like this?  What other information from
> the crash dumps would be useful?

Have you filed a PR on this?  One of my machines started doing
something similar to your last panic:

uvm_fault(0xffffffff81041020, 0x0, 1) -> e
fatal page fault in supervisor mode
trap type 6 code 0 rip ffffffff809c29bd cs 8 rflags 10202 cr2 12 ilevel
0 rsp fffffe810ed60b00 curlwp 0xfffffe823ce98780 pid 0.95 lowest kstack
0xfffffe810ed5e2c0 panic: trap
cpu6: Begin traceback...
vpanic() at netbsd:vpanic+0x13c
snprintf() at netbsd:snprintf
startlwp() at netbsd:startlwp
alltraps() at netbsd:alltraps+0x96
uvm_pagefree() at netbsd:uvm_pagefree+0xd4
genfs_do_putpages() at netbsd:genfs_do_putpages+0xce0
VOP_PUTPAGES() at netbsd:VOP_PUTPAGES+0x3a
uvm_pageout() at netbsd:uvm_pageout+0x2f1
cpu6: End traceback...
uvm_fault(0xfffffe813bd35e70, 0x0, 2) -> e
fatal page fault in supervisor mode
trap type 6 code 2 rip ffffffff805ac769 cs 8 rflags 10202 cr2 84 ilevel
8 rsp fffffe806abeed98 curlwp 0xfffffe80a5198b60 pid 1766.1 lowest
kstack 0xfffffe806abec2c0

dumping to dev 18,1 (offset=18259895, size=2092553):

but I havn't investigated as to what's up yet....  (it crashed Oct 13,
and then Nov 7 and Nov 8... )

Later...

Greg Oster