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Date:   Thu, 20 Jan 2022 06:21:26 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Daniel Wagner <dwagner@suse.de>
Cc:     Ming Lei <ming.lei@redhat.com>, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, Jens Axboe <axboe@kernel.dk>,
        Hannes Reinecke <hare@suse.de>
Subject: Re: [PATCH 2/2] block: hold queue lock while iterating in
 diskstats_show
Message-ID: <Yelv5kTzQGOyucIS@infradead.org>
References: <20220120105248.117025-1-dwagner@suse.de>
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 <20220120140126.ntzvrcmczd7pph75@carbon.lan>
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On Thu, Jan 20, 2022 at 03:01:26PM +0100, Daniel Wagner wrote:
> On Thu, Jan 20, 2022 at 09:51:18PM +0800, Ming Lei wrote:
> > Then Can you figure out where blk_mq_queue_tag_busy_iter+0x1e4 points to
> > in source code? And what is NULL pointer?
> 
> Here we go:
> 
> /usr/src/debug/kernel-default-5.3.18-59.27.1.x86_64/linux-5.3/linux-obj/../include/linux/sbitmap.h: 249

That looks quite old.  How does this look on mainline?