From: Christoph Hellwig <hch@lst.de>
To: Qian Cai <cai@lca.pw>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
dm-devel@redhat.com, linux-kernel@vger.kernel.org,
linux-m68k@lists.linux-m68k.org, linux-xtensa@linux-xtensa.org,
drbd-dev@lists.linbit.com, linuxppc-dev@lists.ozlabs.org,
linux-bcache@vger.kernel.org, linux-raid@vger.kernel.org,
linux-nvdimm@lists.01.org, linux-nvme@lists.infradead.org,
linux-s390@vger.kernel.org,
Andrey Ryabinin <aryabinin@virtuozzo.com>,
Alexander Potapenko <glider@google.com>,
Dmitry Vyukov <dvyukov@google.com>,
kasan-dev@googlegroups.com
Subject: Re: [PATCH 18/20] block: refator submit_bio_noacct
Date: Thu, 2 Jul 2020 17:14:53 +0200 [thread overview]
Message-ID: <20200702151453.GA1799@lst.de> (raw)
In-Reply-To: <20200702141001.GA3834@lca.pw>
On Thu, Jul 02, 2020 at 10:10:10AM -0400, Qian Cai wrote:
> On Mon, Jun 29, 2020 at 09:39:45PM +0200, Christoph Hellwig wrote:
> > Split out a __submit_bio_noacct helper for the actual de-recursion
> > algorithm, and simplify the loop by using a continue when we can't
> > enter the queue for a bio.
> >
> > Signed-off-by: Christoph Hellwig <hch@lst.de>
>
> Reverting this commit and its dependencies,
>
> 5a6c35f9af41 block: remove direct_make_request
> ff93ea0ce763 block: shortcut __submit_bio_noacct for blk-mq drivers
>
> fixed the stack-out-of-bounds during boot,
>
> https://lore.kernel.org/linux-block/000000000000bcdeaa05a97280e4@google.com/
Yikes. bio_alloc_bioset pokes into bio_list[1] in a totally
undocumented way. But even with that the problem should only show
up with "block: shortcut __submit_bio_noacct for blk-mq drivers".
Can you try this patch?
diff --git a/block/blk-core.c b/block/blk-core.c
index bf882b8d84450c..9f1bf8658b611a 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1155,11 +1155,10 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio)
static blk_qc_t __submit_bio_noacct_mq(struct bio *bio)
{
struct gendisk *disk = bio->bi_disk;
- struct bio_list bio_list;
+ struct bio_list bio_list[2] = { };
blk_qc_t ret = BLK_QC_T_NONE;
- bio_list_init(&bio_list);
- current->bio_list = &bio_list;
+ current->bio_list = bio_list;
do {
WARN_ON_ONCE(bio->bi_disk != disk);
@@ -1174,7 +1173,7 @@ static blk_qc_t __submit_bio_noacct_mq(struct bio *bio)
}
ret = blk_mq_submit_bio(bio);
- } while ((bio = bio_list_pop(&bio_list)));
+ } while ((bio = bio_list_pop(&bio_list[0])));
current->bio_list = NULL;
return ret;
next prev parent reply other threads:[~2020-07-02 15:14 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-29 19:39 rename ->make_request_fn and move it to the block_device_operations Christoph Hellwig
2020-06-29 19:39 ` [PATCH 01/20] nfblock: stop using ->queuedata Christoph Hellwig
2020-06-29 21:47 ` Geert Uytterhoeven
2020-06-29 19:39 ` [PATCH 02/20] simdisk: " Christoph Hellwig
2020-06-29 19:39 ` [PATCH 03/20] drbd: " Christoph Hellwig
2020-06-29 19:39 ` [PATCH 04/20] null_blk: stop using ->queuedata for bio mode Christoph Hellwig
2020-06-29 19:39 ` [PATCH 05/20] ps3vram: stop using ->queuedata Christoph Hellwig
2020-06-29 19:39 ` [PATCH 06/20] rsxx: " Christoph Hellwig
2020-06-29 19:39 ` [PATCH 07/20] umem: " Christoph Hellwig
2020-06-29 19:39 ` [PATCH 08/20] zram: " Christoph Hellwig
2020-06-29 19:39 ` [PATCH 09/20] bcache: stop setting ->queuedata Christoph Hellwig
2020-06-29 19:39 ` [PATCH 10/20] dm: stop using ->queuedata Christoph Hellwig
2020-06-29 19:39 ` [PATCH 11/20] fs: remove a weird comment in submit_bh_wbc Christoph Hellwig
2020-06-30 13:54 ` Jens Axboe
2020-06-29 19:39 ` [PATCH 12/20] block: remove the request_queue argument from blk_queue_split Christoph Hellwig
2020-06-29 19:39 ` [PATCH 13/20] block: tidy up a warning in bio_check_ro Christoph Hellwig
2020-06-29 19:39 ` [PATCH 14/20] block: remove the NULL queue check in generic_make_request_checks Christoph Hellwig
2020-06-29 19:39 ` [PATCH 15/20] block: remove the nr_sectors variable " Christoph Hellwig
2020-06-29 19:39 ` [PATCH 16/20] block: move ->make_request_fn to struct block_device_operations Christoph Hellwig
2020-06-29 19:39 ` [PATCH 17/20] block: rename generic_make_request to submit_bio_noacct Christoph Hellwig
2020-06-29 19:39 ` [PATCH 18/20] block: refator submit_bio_noacct Christoph Hellwig
2020-07-02 14:10 ` Qian Cai
2020-07-02 15:14 ` Christoph Hellwig [this message]
2020-07-02 15:52 ` Naresh Kamboju
2020-07-02 15:15 ` Naresh Kamboju
2020-06-29 19:39 ` [PATCH 19/20] block: shortcut __submit_bio_noacct for blk-mq drivers Christoph Hellwig
2020-06-29 19:39 ` [PATCH 20/20] block: remove direct_make_request Christoph Hellwig
2020-06-30 13:57 ` rename ->make_request_fn and move it to the block_device_operations Jens Axboe
2020-06-30 15:43 ` Jens Axboe
2020-06-30 18:19 ` Christoph Hellwig
2020-06-30 18:21 ` Jens Axboe
2020-07-01 8:59 rename ->make_request_fn and move it to the block_device_operations v2 Christoph Hellwig
2020-07-01 8:59 ` [PATCH 18/20] block: refator submit_bio_noacct Christoph Hellwig
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