Re: panic: Assertion lock == sq->sq_lock failed at /usr/src-13/sys/kern/subr_sleepqueue.c:371

From: Grzegorz Junka <list1_at_gjunka.com>
Date: Sun, 3 May 2020 14:11:09 +0100
On 03/05/2020 08:05, Gary Jennejohn wrote:
> On Sat, 02 May 2020 16:28:46 -0700
> Chris <bsd-lists_at_BSDforge.com> wrote:
>
>>
>>>
>>>>> Another thing is that I don't quite understand why the crash couldn't
>>>>> be dumped.
>>>>>
>>>>> root_at_crayon2:~ # swapinfo
>>>>> Device__________________ 1K-blocks________ Used______ Avail Capacity
>>>>> /dev/zvol/tank3/swap__ 33554432______________ 0 33554432________ 0%
>>>>>
>>>>> There is no entry in /etc/fstab though, should it be there too?
>>>> How about your rc.conf(5) ?
>>>>
>>>> You need to define a dumpdev within it as:
>>>>
>>>> # Set dumpdev to "AUTO" to enable crash dumps, "NO" to disable
>>>> dumpdev="YES"
>>>>
>>>> Which defaults to the location of:
>>>>
>>>> /var/crash
>>>>   
>>> Yes, of course I have 'dumpdev="AUTO"'. Should it be "YES" instead?
>> Yes, it should of course be AUTO. I was distracted at the time of writing.
>> Sorry.
>> Does /var/crash exist?
>>
>> That _should_ be enough. Assuming /var/crash is writable.
>>
> Sorry, but read the man page for rc.conf.
>
> This is the entry for dumpdev:
>
>       dumpdev     (str) Indicates the device (usually a swap partition) to
>                   which a crash dump should be written in the event of a system
>                   crash.  If the value of this variable is "AUTO", the first
>                   suitable swap device listed in /etc/fstab will be used as
>                   dump device.  Otherwise, the value of this variable is passed
>                   as the argument to dumpon(8).  To disable crash dumps, set
>                   this variable to "NO".
>
> If there are no swap devices in /etc/fstab then "AUTO" will not work.  But
> a partition can be specified.  I have dumpdev="/dev/ada0p5" in my rc.conf.
>
> /var/crash is the target for crash dumps after the system is re-booted.
>

/var/crash existed but might not have had the right permissions. I think 
it was 755 whereas the handbook recommends 700. Shouldn't matter though.

I don't have anything about swap in fstab since I am using Root on ZFS. 
swapinfo correctly recognizes the swap partition and uses it. This the 
typical usage while I am compiling ports:

last pid: 85116;  load averages:  8.95,  8.50, 8.34 up 0+18:06:31  13:02:32
72 processes:  14 running, 57 sleeping, 1 zombie
CPU:  0.0% user, 90.5% nice,  9.5% system,  0.0% interrupt,  0.0% idle
Mem: 993M Active, 594M Inact, 6400K Laundry, 12G Wired, 2225M Free
ARC: 6160M Total, 3093M MFU, 2657M MRU, 214M Anon, 100M Header, 193M Other
      5300M Compressed, 5861M Uncompressed, 1.11:1 Ratio
Swap: 32G Total, 61M Used, 32G Free

The crash happened in similar conditions so there should be nothing 
preventing dumping the crash to the zfs swap, unless dumpon isn't smart 
enough to use zfs swap.

I don't have a partition that I could use for swap. I have two whole 
disks added to ZFS. Maybe on the boot drive but that would require 
repartitioning and I have Windows/FreeBSD there, so not so straightforward.

--GrzegorzJ
Received on Sun May 03 2020 - 11:11:19 UTC

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