Message-ID: <4321724d-9a24-926c-5d2d-5d5d902bda72@kernel.dk>
Date:   Tue, 7 Feb 2023 11:31:47 -0700
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Subject: Re: block: sleeping in atomic warnings
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To:     Dan Carpenter <error27@gmail.com>, linux-block@vger.kernel.org
Cc:     Julia Lawall <julia.lawall@inria.fr>,
        Luis Chamberlain <mcgrof@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Hongchen Zhang <zhanghongchen@loongson.cn>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Andrew Morton <akpm@linux-foundation.org>,
        "Christian Brauner (Microsoft)" <brauner@kernel.org>,
        David Howells <dhowells@redhat.com>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Eric Dumazet <edumazet@google.com>,
        "Fabio M. De Francesco" <fmdefrancesco@gmail.com>,
        Christophe JAILLET <christophe.jaillet@wanadoo.fr>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        maobibo <maobibo@loongson.cn>,
        Matthew Wilcox <willy@infradead.org>,
        Sedat Dilek <sedat.dilek@gmail.com>
References: <20230129060452.7380-1-zhanghongchen@loongson.cn>
 <CAHk-=wjw-rrT59k6VdeLu4qUarQOzicsZPFGAO5J8TKM=oukUw@mail.gmail.com>
 <Y+EjmnRqpLuBFPX1@bombadil.infradead.org>
 <4ffbb0c8-c5d0-73b3-7a4e-2da9a7b03669@inria.fr> <Y+Ja5SRs886CEz7a@kadam>
From:   Jens Axboe <axboe@kernel.dk>
In-Reply-To: <Y+Ja5SRs886CEz7a@kadam>
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Precedence: bulk

On 2/7/23 7:06?AM, Dan Carpenter wrote:
> block/blk-mq.c:206 blk_freeze_queue() warn: sleeping in atomic context
> rexmit_timer() <- disables preempt
> -> aoedev_downdev()
>    -> blk_mq_freeze_queue()
>       -> blk_freeze_queue()

That is definitely a legit bug, aoe should punt to a workqueue or
similar.

> block/blk-mq.c:4083 blk_mq_destroy_queue() warn: sleeping in atomic context
> nvme_fc_match_disconn_ls() <- disables preempt
> -> nvme_fc_ctrl_put()
>    -> nvme_fc_ctrl_free()
>       -> nvme_remove_admin_tag_set()
> nvme_fc_ctrl_free() <duplicate>
> -> nvme_remove_io_tag_set()
>          -> blk_mq_destroy_queue()

Also looks like a legitimate bug.

> block/blk-mq.c:2174 __blk_mq_run_hw_queue() warn: sleeping in atomic context
> __blk_mq_run_hw_queue() <duplicate>
> -> blk_mq_sched_dispatch_requests()
>    -> __blk_mq_sched_dispatch_requests()
>       -> blk_mq_do_dispatch_sched()
> blk_mq_do_dispatch_sched() <duplicate>
> -> __blk_mq_do_dispatch_sched()
>    -> blk_mq_dispatch_hctx_list()
> __blk_mq_do_dispatch_sched() <duplicate>
> __blk_mq_sched_dispatch_requests() <duplicate>
> -> blk_mq_do_dispatch_ctx()
> __blk_mq_sched_dispatch_requests() <duplicate>
>       -> blk_mq_dispatch_rq_list()
> __blk_mq_do_dispatch_sched() <duplicate>
> blk_mq_do_dispatch_ctx() <duplicate>
> -> blk_mq_delay_run_hw_queues()
>          -> blk_mq_delay_run_hw_queue()

This one I'm not really following... Would it be possible to expand the
reporting to be a bit more verbose?

> sg_remove_sfp_usercontext() <- disables preempt
> block/blk-wbt.c:843 wbt_init() warn: sleeping in atomic context
> ioc_qos_write() <- disables preempt
> -> wbt_enable_default()
>    -> wbt_init()

Also definitely a bug.

-- 
Jens Axboe