On Fri, Jan 5, 2018 at 8:32 AM, Bart Van Assche <Bart.VanAssche@xxxxxxx> wrote:
> On Thu, 2018-01-04 at 14:32 -0800, Vinson Lee wrote:
>> HP ProLiant DL360p Gen8 with Smart Array P420i boots to the login
>> prompt and hangs with Linux 4.13 or later. I cannot log in on console
>> or SSH into the machine. Linux 4.12 and older boot fine.
>>
>> I see these messages on the console.
>>
>> [ 242.843206] INFO: task scsi_eh_2:465 blocked for more than 120 seconds.
>> [ 242.877835] Not tainted 4.15.0-041500rc6-generic #201712312330
>
> It seems like something got stuck in the block layer. The traditional way to
> debug this is to analyze the information that is available under
> /sys/kernel/debug/block. However, since login is not possible we can't use
> that approach. Would it be possible for you to check whether this has been
> resolved in kernel v4.15-rc6, and if not, bisect this?
>
> Thanks,
>
> Bart.
Hi.
The machine still hangs with Linux 4.15-rc6.
I did a bisect. The hang is introduced with Linux 4.13-rc1 commit
c5cb83bb337c25caae995d992d1cdf9b317f83de "genirq/cpuhotplug: Handle
managed IRQs on CPU hotplug".
There is a startup script that disables hyperthreading by offlining
sibling CPUs.
for CPU in $(cut -s -d, -f2
$SYS_PATH/cpu*/topology/thread_siblings_list | sort -un); do
echo 0 > /sys/devices/system/cpu/cpu$CPU/online
done
If the above script is not run, the machine does not hang with Linux 4.13.
Cheers,
Vinson
