From mboxrd@z Thu Jan  1 00:00:00 1970
From: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Subject: Re: hung-task panic in raid5_make_request
Date: Mon, 13 Jan 2020 12:10:47 +0100
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To: Alexander Lyakas <alex.bolshoy@gmail.com>
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Hi Alex,

On 1/12/20 8:46 AM, Alexander Lyakas wrote:
> Hi Guoqing,
>
> We have tried the proposed patch, but still hit the hung-task panic in
> the same place[1]. How can we debug this further?

Can you print the information (atomic_read(&conf->active_stripes),
conf->max_nr_stripes and conf->cache_state)  just before the
wait_event_lock_irq? Then we can verify which condition is not meet
here. Also pls dump the value of sysfs nodes, something like.

linux:/sys/block/md5/md # find -mindepth 1 -maxdepth 1 -type 
f|sort|xargs -r egrep .


BTW, could you try latest kernel? And is it possible to reproduce the panic?

Thanks,
Guoqing