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From: Bart Van Assche <bvanassche@acm.org>
To: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org, Christoph Hellwig <hch@lst.de>,
	Bart Van Assche <bvanassche@acm.org>
Subject: [PATCH v2 0/2] Fix a race condition triggered by submit_bio()
Date: Tue, 30 Jul 2019 11:36:51 -0700	[thread overview]
Message-ID: <20190730183653.253579-1-bvanassche@acm.org> (raw)

Hi Jens,

One of the consequences of the switch to blk-mq is that generic_make_request()
calls, a function called by submit_bio(), must be protected by a
blk_queue_enter() / blk_queue_exit() pair to avoid that the block-cgroup
functions called by generic_make_request() trigger a race condition. This patch
series makes the kernel report a warning if that race condition is hit and also
adds the necessary protection in submit_bio(). Please consider these patches
for kernel v5.4.

Thanks,

Bart.

Changes compared to v1:
- Use the full syzbot ID in patch 2/2 instead of abbreviating it.

Bart Van Assche (2):
  block: Verify whether blk_queue_enter() is used when necessary
  block: Fix a race condition in submit_bio()

 block/blk-cgroup.c         |  2 ++
 block/blk-core.c           | 34 +++++++++++++++++++++++++++++++++-
 include/linux/blk-cgroup.h |  2 ++
 include/linux/blkdev.h     |  8 ++++++++
 4 files changed, 45 insertions(+), 1 deletion(-)

-- 
2.22.0.709.g102302147b-goog


             reply	other threads:[~2019-07-30 18:37 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-30 18:36 Bart Van Assche [this message]
2019-07-30 18:36 ` [PATCH v2 1/2] block: Verify whether blk_queue_enter() is used when necessary Bart Van Assche
2019-07-30 18:36 ` [PATCH v2 2/2] block: Fix a race condition in submit_bio() Bart Van Assche

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