Re: Deadlocks / hangs in ZFS

Quoting Alexander Leidinger <Alexander_at_leidinger.net> (from Mon, 28  
May 2018 09:02:01 +0200):

> Quoting Slawa Olhovchenkov <slw_at_zxy.spb.ru> (from Mon, 28 May 2018  
> 01:06:12 +0300):
>
>> On Sun, May 27, 2018 at 09:41:59PM +0200, Kirill Ponomarev wrote:
>>
>>> On 05/22, Slawa Olhovchenkov wrote:
>>>> > It has been a while since I tried Karl's patch the last time, and I
>>>> > stopped because it didn't apply to -current anymore at some point.
>>>> > Will what is provided right now in the patch work on -current?
>>>>
>>>> I am mean yes, after s/vm_cnt.v_free_count/vm_free_count()/g
>>>> I am don't know how to have two distinct patch (for stable and  
>>>> current) in one review.
>>>
>>> I'm experiencing these issues sporadically as well, would you mind
>>> to publish this patch for fresh current?
>>
>> Week ago I am adopt and publish patch to fresh current and stable, is
>> adopt need again?
>
> I applied the patch in the review yesterday to rev 333966, it  
> applied OK (with some fuzz). I will try to reproduce my issue with  
> the patch.

The behavior changed (or the system was long enough in this state  
without me noticing it). I have a panic now:
panic: deadlkres: possible deadlock detected for 0xfffff803766db580,  
blocked for 1803003 ticks

I only have the textdump. Is nayone up to debug this? If yes, I switch  
to normal dumps, just tell me what I shall check for.

db:0:kdb.enter.panic>  run lockinfo
db:1:lockinfo> show locks
No such command; use "help" to list available commands
db:1:lockinfo>  show alllocks
No such command; use "help" to list available commands
db:1:lockinfo>  show lockedvnods
Locked vnodes
db:0:kdb.enter.panic>  show pcpu
cpuid        = 6
dynamic pcpu = 0xfffffe008f03e840
curthread    = 0xfffff80370c82000: pid 0 tid 100218 "deadlkres"
curpcb       = 0xfffffe0116472cc0
fpcurthread  = none
idlethread   = 0xfffff803700b9580: tid 100008 "idle: cpu6"
curpmap      = 0xffffffff80d28448
tssp         = 0xffffffff80d96d90
commontssp   = 0xffffffff80d96d90
rsp0         = 0xfffffe0116472cc0
gs32p        = 0xffffffff80d9d9c8
ldt          = 0xffffffff80d9da08
tss          = 0xffffffff80d9d9f8
db:0:kdb.enter.panic>  bt
Tracing pid 0 tid 100218 td 0xfffff80370c82000
kdb_enter() at kdb_enter+0x3b/frame 0xfffffe0116472aa0
vpanic() at vpanic+0x1c0/frame 0xfffffe0116472b00
panic() at panic+0x43/frame 0xfffffe0116472b60
deadlkres() at deadlkres+0x3a6/frame 0xfffffe0116472bb0
fork_exit() at fork_exit+0x84/frame 0xfffffe0116472bf0
fork_trampoline() at fork_trampoline+0xe/frame 0xfffffe0116472bf0
--- trap 0, rip = 0, rsp = 0, rbp = 0 ---


Bye,
Alexander.

-- 
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