On 2017-04-27 10:58:36 [+0800], kernel test robot wrote:
> 
> FYI, we noticed the following commit:
> 
> commit: 924726b2b5e5000dfb8eb6032651baed1b1bdc6c ("perf: Cure hotplug lock ordering issues")
> https://git.kernel.org/cgit/linux/kernel/git/tip/tip.git smp/hotplug

I can't find that commit in tip so I used
   14aff62ede39 ("perf: Cure hotplug lock ordering issues")

which should be the same thing.

> in testcase: boot
> 
> on test machine: qemu-system-x86_64 -enable-kvm -smp 2 -m 512M

I booted this. I grabbed the command line the yaml file attached and
quantal-core-x86_64.cgz from github.

> [  203.023547] mmap: trinity-c0 (2509) uses deprecated remap_file_pages() syscall. See Documentation/vm/remap_file_pages.txt.
> [child0:2509] uid changed! Was: 0, now 252
> [child1:2511] child exiting.
> Bailing main loop. Exit reason: UID changed.
> [watchdog] [2502] Watchdog exiting
> [  204.078036] double fault: 0000 [#1] SMP DEBUG_PAGEALLOC
> [  204.078036] double fault: 0000 [#1] SMP DEBUG_PAGEALLOC

I don't see that.

> To reproduce:
> 
>         git clone https://github.com/01org/lkp-tests.git
>         cd lkp-tests
>         bin/lkp qemu -k <bzImage> job-script  # job-script is attached in this email

I tried that, too. The difference between running qemu manually and this
seems that the manual approach runs the kernel a few times while this
aborts after the first run. I attached my manual run. It looks similar
(including the trinity segfault) but the kernels runs smooth.

You don't seem to inject / load the kernels modules you compile.

> Thanks,
> Xiaolong

Sebastian