IRQ/nvme_pci_complete_rq: NULL pointer dereference yet again

[Alex G.]

On 04/09/2018 02:47 PM, Keith Busch wrote:
> On Mon, Apr 09, 2018 at 02:36:30PM -0500, Alex G. wrote:
>> Although I remember a time when I could run these sort of tests without
>> panic(), I don't have a solid base from which I can bisect things.
>> Especially since we've added a few fixes lately that won't be in any base.
>>
>> I'll try a couple of branches, but don't hold your breath.
> 
> This may be a regression.

It is. 4.16-rc7+ (+nsid duplicate and device free patches) does not
crash, or cause kasan to complain. However axboe/linux-block/for-next
exhibits the issue. I'm getting ready to also test for-4.17/block, and
then your AER patches.

> Your panic is triggered through the timeout
> path, which appears to have had recent modifications that are included
> in your kernel. There's at least one issue in this area:
> 
>   https://marc.info/?l=linux-block&m=152325124306821&w=2
> 
> I haven't looked into it enough to know if it's related to this issue,
> though.

Thanks. I'll grab a look tomorrow and see if that fixes the issue.

Alex