On Mon, Aug 15, 2016 at 6:22 PM, Bart Van Assche
[off-list ref] wrote:

On 08/15/2016 09:01 AM, Jinpu Wang wrote:

quoted

It's more likely you hit another bug, my colleague Roman fix that:

http://www.spinics.net/lists/linux-block/msg04552.html

Hello Jinpu,

Interesting. However, I see that wrote the following: "Firstly this wrong
sequence raises two kernel warnings: 1st. WARNING at
lib/percpu-recount.c:309 percpu_ref_kill_and_confirm called more than onc=

e

2nd. WARNING at lib/percpu-refcount.c:331". I haven't seen any of these
kernel warnings ...

Thanks,

Bart.

The warning happened from time to time, but your hung tasks are
similar with ours.
We injected some delay in order to reproduce easily.


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Best Regards,

Jack Wang

Linux Kernel Developer Storage
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