* Re: Patch "bcache: fix improper use of bi_end_io" has been added to the 6.6-stable tree
[not found] <20260112172345.800703-1-sashal@kernel.org>
@ 2026-01-12 17:34 ` Kent Overstreet
2026-01-12 18:01 ` Kent Overstreet
2026-01-15 8:47 ` Kent Overstreet
2 siblings, 0 replies; 7+ messages in thread
From: Kent Overstreet @ 2026-01-12 17:34 UTC (permalink / raw)
To: stable; +Cc: stable-commits, zhangshida, Coly Li
On Mon, Jan 12, 2026 at 12:23:45PM -0500, Sasha Levin wrote:
> This is a note to let you know that I've just added the patch titled
>
> bcache: fix improper use of bi_end_io
>
> to the 6.6-stable tree which can be found at:
> http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
>
> The filename of the patch is:
> bcache-fix-improper-use-of-bi_end_io.patch
> and it can be found in the queue-6.6 subdirectory.
>
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable@vger.kernel.org> know about it.
Has this code been tested?
bio_endio() is not equivalent to calling bi_end_io; if the code is
swapping out bi_end_io to pass it down the stack, then you have two
completions on the same bio - you cannot call bio_endio() twice on the
same bio.
>
>
>
> commit 81e7e43a810e8f40e163928d441de02d2816b073
> Author: Shida Zhang <zhangshida@kylinos.cn>
> Date: Tue Dec 9 17:01:56 2025 +0800
>
> bcache: fix improper use of bi_end_io
>
> [ Upstream commit 53280e398471f0bddbb17b798a63d41264651325 ]
>
> Don't call bio->bi_end_io() directly. Use the bio_endio() helper
> function instead, which handles completion more safely and uniformly.
>
> Suggested-by: Christoph Hellwig <hch@infradead.org>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
> Signed-off-by: Jens Axboe <axboe@kernel.dk>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
>
> diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
> index a9b1f3896249b..b4059d2daa326 100644
> --- a/drivers/md/bcache/request.c
> +++ b/drivers/md/bcache/request.c
> @@ -1090,7 +1090,7 @@ static void detached_dev_end_io(struct bio *bio)
> }
>
> kfree(ddip);
> - bio->bi_end_io(bio);
> + bio_endio(bio);
> }
>
> static void detached_dev_do_request(struct bcache_device *d, struct bio *bio,
> @@ -1107,7 +1107,7 @@ static void detached_dev_do_request(struct bcache_device *d, struct bio *bio,
> ddip = kzalloc(sizeof(struct detached_dev_io_private), GFP_NOIO);
> if (!ddip) {
> bio->bi_status = BLK_STS_RESOURCE;
> - bio->bi_end_io(bio);
> + bio_endio(bio);
> return;
> }
>
> @@ -1122,7 +1122,7 @@ static void detached_dev_do_request(struct bcache_device *d, struct bio *bio,
>
> if ((bio_op(bio) == REQ_OP_DISCARD) &&
> !bdev_max_discard_sectors(dc->bdev))
> - bio->bi_end_io(bio);
> + detached_dev_end_io(bio);
> else
> submit_bio_noacct(bio);
> }
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: Patch "bcache: fix improper use of bi_end_io" has been added to the 6.6-stable tree
[not found] <20260112172345.800703-1-sashal@kernel.org>
2026-01-12 17:34 ` Patch "bcache: fix improper use of bi_end_io" has been added to the 6.6-stable tree Kent Overstreet
@ 2026-01-12 18:01 ` Kent Overstreet
2026-01-13 6:08 ` Coly Li
2026-01-15 8:47 ` Kent Overstreet
2 siblings, 1 reply; 7+ messages in thread
From: Kent Overstreet @ 2026-01-12 18:01 UTC (permalink / raw)
To: stable; +Cc: stable-commits, zhangshida, Coly Li
On Mon, Jan 12, 2026 at 12:23:45PM -0500, Sasha Levin wrote:
> This is a note to let you know that I've just added the patch titled
>
> bcache: fix improper use of bi_end_io
>
> to the 6.6-stable tree which can be found at:
> http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
>
> The filename of the patch is:
> bcache-fix-improper-use-of-bi_end_io.patch
> and it can be found in the queue-6.6 subdirectory.
>
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable@vger.kernel.org> know about it.
Yeah, this is broken.
Coly, please revert this.
>
>
>
> commit 81e7e43a810e8f40e163928d441de02d2816b073
> Author: Shida Zhang <zhangshida@kylinos.cn>
> Date: Tue Dec 9 17:01:56 2025 +0800
>
> bcache: fix improper use of bi_end_io
>
> [ Upstream commit 53280e398471f0bddbb17b798a63d41264651325 ]
>
> Don't call bio->bi_end_io() directly. Use the bio_endio() helper
> function instead, which handles completion more safely and uniformly.
>
> Suggested-by: Christoph Hellwig <hch@infradead.org>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
> Signed-off-by: Jens Axboe <axboe@kernel.dk>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
>
> diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
> index a9b1f3896249b..b4059d2daa326 100644
> --- a/drivers/md/bcache/request.c
> +++ b/drivers/md/bcache/request.c
> @@ -1090,7 +1090,7 @@ static void detached_dev_end_io(struct bio *bio)
> }
>
> kfree(ddip);
> - bio->bi_end_io(bio);
> + bio_endio(bio);
> }
>
> static void detached_dev_do_request(struct bcache_device *d, struct bio *bio,
> @@ -1107,7 +1107,7 @@ static void detached_dev_do_request(struct bcache_device *d, struct bio *bio,
> ddip = kzalloc(sizeof(struct detached_dev_io_private), GFP_NOIO);
> if (!ddip) {
> bio->bi_status = BLK_STS_RESOURCE;
> - bio->bi_end_io(bio);
> + bio_endio(bio);
> return;
> }
>
> @@ -1122,7 +1122,7 @@ static void detached_dev_do_request(struct bcache_device *d, struct bio *bio,
>
> if ((bio_op(bio) == REQ_OP_DISCARD) &&
> !bdev_max_discard_sectors(dc->bdev))
> - bio->bi_end_io(bio);
> + detached_dev_end_io(bio);
> else
> submit_bio_noacct(bio);
> }
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: Patch "bcache: fix improper use of bi_end_io" has been added to the 6.6-stable tree
2026-01-12 18:01 ` Kent Overstreet
@ 2026-01-13 6:08 ` Coly Li
2026-01-13 6:21 ` Kent Overstreet
0 siblings, 1 reply; 7+ messages in thread
From: Coly Li @ 2026-01-13 6:08 UTC (permalink / raw)
To: Kent Overstreet; +Cc: stable, stable-commits, zhangshida
On Mon, Jan 12, 2026 at 01:01:52PM +0800, Kent Overstreet wrote:
> On Mon, Jan 12, 2026 at 12:23:45PM -0500, Sasha Levin wrote:
> > This is a note to let you know that I've just added the patch titled
> >
> > bcache: fix improper use of bi_end_io
> >
> > to the 6.6-stable tree which can be found at:
> > http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> >
> > The filename of the patch is:
> > bcache-fix-improper-use-of-bi_end_io.patch
> > and it can be found in the queue-6.6 subdirectory.
> >
> > If you, or anyone else, feels it should not be added to the stable tree,
> > please let <stable@vger.kernel.org> know about it.
>
> Yeah, this is broken.
>
> Coly, please revert this.
>
Yes, let me do it.
Although I didn’t ack this patch, I read the patch and thought it was
fine, yes my fault too.
This faulty patch didn’t trigger issue on my testing machine, I guess
it was because on simple bcache setup, re-enter bio_endio() happenly
didn't actually redo things other than calling bio->bi_end_io().
I will post a revert commit to Jens.
This patch is part of the patch set to address race around bio chain
handling. Then Shida please continue to find a better version on the
fix.
Coly Li
> >
> >
> >
> > commit 81e7e43a810e8f40e163928d441de02d2816b073
> > Author: Shida Zhang <zhangshida@kylinos.cn>
> > Date: Tue Dec 9 17:01:56 2025 +0800
> >
> > bcache: fix improper use of bi_end_io
> >
> > [ Upstream commit 53280e398471f0bddbb17b798a63d41264651325 ]
> >
> > Don't call bio->bi_end_io() directly. Use the bio_endio() helper
> > function instead, which handles completion more safely and uniformly.
> >
> > Suggested-by: Christoph Hellwig <hch@infradead.org>
> > Reviewed-by: Christoph Hellwig <hch@lst.de>
> > Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
> > Signed-off-by: Jens Axboe <axboe@kernel.dk>
> > Signed-off-by: Sasha Levin <sashal@kernel.org>
> >
> > diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
> > index a9b1f3896249b..b4059d2daa326 100644
> > --- a/drivers/md/bcache/request.c
> > +++ b/drivers/md/bcache/request.c
> > @@ -1090,7 +1090,7 @@ static void detached_dev_end_io(struct bio *bio)
> > }
> >
> > kfree(ddip);
> > - bio->bi_end_io(bio);
> > + bio_endio(bio);
> > }
> >
> > static void detached_dev_do_request(struct bcache_device *d, struct bio *bio,
> > @@ -1107,7 +1107,7 @@ static void detached_dev_do_request(struct bcache_device *d, struct bio *bio,
> > ddip = kzalloc(sizeof(struct detached_dev_io_private), GFP_NOIO);
> > if (!ddip) {
> > bio->bi_status = BLK_STS_RESOURCE;
> > - bio->bi_end_io(bio);
> > + bio_endio(bio);
> > return;
> > }
> >
> > @@ -1122,7 +1122,7 @@ static void detached_dev_do_request(struct bcache_device *d, struct bio *bio,
> >
> > if ((bio_op(bio) == REQ_OP_DISCARD) &&
> > !bdev_max_discard_sectors(dc->bdev))
> > - bio->bi_end_io(bio);
> > + detached_dev_end_io(bio);
> > else
> > submit_bio_noacct(bio);
> > }
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: Patch "bcache: fix improper use of bi_end_io" has been added to the 6.6-stable tree
2026-01-13 6:08 ` Coly Li
@ 2026-01-13 6:21 ` Kent Overstreet
0 siblings, 0 replies; 7+ messages in thread
From: Kent Overstreet @ 2026-01-13 6:21 UTC (permalink / raw)
To: Coly Li; +Cc: stable, stable-commits, zhangshida
On Tue, Jan 13, 2026 at 02:08:27PM +0800, Coly Li wrote:
> On Mon, Jan 12, 2026 at 01:01:52PM +0800, Kent Overstreet wrote:
> > On Mon, Jan 12, 2026 at 12:23:45PM -0500, Sasha Levin wrote:
> > > This is a note to let you know that I've just added the patch titled
> > >
> > > bcache: fix improper use of bi_end_io
> > >
> > > to the 6.6-stable tree which can be found at:
> > > http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> > >
> > > The filename of the patch is:
> > > bcache-fix-improper-use-of-bi_end_io.patch
> > > and it can be found in the queue-6.6 subdirectory.
> > >
> > > If you, or anyone else, feels it should not be added to the stable tree,
> > > please let <stable@vger.kernel.org> know about it.
> >
> > Yeah, this is broken.
> >
> > Coly, please revert this.
> >
>
> Yes, let me do it.
>
> Although I didn’t ack this patch, I read the patch and thought it was
> fine, yes my fault too.
>
> This faulty patch didn’t trigger issue on my testing machine, I guess
> it was because on simple bcache setup, re-enter bio_endio() happenly
> didn't actually redo things other than calling bio->bi_end_io().
Yeah, re-entering bio_endio() will work on simple setups - but it'll
explode as soon as bio splitting starts happening.
You really want to be going over anything Christoph does with a fine
toothed comb.
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: Patch "bcache: fix improper use of bi_end_io" has been added to the 6.6-stable tree
[not found] <20260112172345.800703-1-sashal@kernel.org>
2026-01-12 17:34 ` Patch "bcache: fix improper use of bi_end_io" has been added to the 6.6-stable tree Kent Overstreet
2026-01-12 18:01 ` Kent Overstreet
@ 2026-01-15 8:47 ` Kent Overstreet
2026-01-15 11:39 ` Greg KH
2 siblings, 1 reply; 7+ messages in thread
From: Kent Overstreet @ 2026-01-15 8:47 UTC (permalink / raw)
To: stable; +Cc: stable-commits, zhangshida, Coly Li
On Mon, Jan 12, 2026 at 12:23:45PM -0500, Sasha Levin wrote:
> This is a note to let you know that I've just added the patch titled
>
> bcache: fix improper use of bi_end_io
>
> to the 6.6-stable tree which can be found at:
> http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
>
> The filename of the patch is:
> bcache-fix-improper-use-of-bi_end_io.patch
> and it can be found in the queue-6.6 subdirectory.
>
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable@vger.kernel.org> know about it.
Sasha, has this been dropped?
>
>
>
> commit 81e7e43a810e8f40e163928d441de02d2816b073
> Author: Shida Zhang <zhangshida@kylinos.cn>
> Date: Tue Dec 9 17:01:56 2025 +0800
>
> bcache: fix improper use of bi_end_io
>
> [ Upstream commit 53280e398471f0bddbb17b798a63d41264651325 ]
>
> Don't call bio->bi_end_io() directly. Use the bio_endio() helper
> function instead, which handles completion more safely and uniformly.
>
> Suggested-by: Christoph Hellwig <hch@infradead.org>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
> Signed-off-by: Jens Axboe <axboe@kernel.dk>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
>
> diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
> index a9b1f3896249b..b4059d2daa326 100644
> --- a/drivers/md/bcache/request.c
> +++ b/drivers/md/bcache/request.c
> @@ -1090,7 +1090,7 @@ static void detached_dev_end_io(struct bio *bio)
> }
>
> kfree(ddip);
> - bio->bi_end_io(bio);
> + bio_endio(bio);
> }
>
> static void detached_dev_do_request(struct bcache_device *d, struct bio *bio,
> @@ -1107,7 +1107,7 @@ static void detached_dev_do_request(struct bcache_device *d, struct bio *bio,
> ddip = kzalloc(sizeof(struct detached_dev_io_private), GFP_NOIO);
> if (!ddip) {
> bio->bi_status = BLK_STS_RESOURCE;
> - bio->bi_end_io(bio);
> + bio_endio(bio);
> return;
> }
>
> @@ -1122,7 +1122,7 @@ static void detached_dev_do_request(struct bcache_device *d, struct bio *bio,
>
> if ((bio_op(bio) == REQ_OP_DISCARD) &&
> !bdev_max_discard_sectors(dc->bdev))
> - bio->bi_end_io(bio);
> + detached_dev_end_io(bio);
> else
> submit_bio_noacct(bio);
> }
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: Patch "bcache: fix improper use of bi_end_io" has been added to the 6.6-stable tree
2026-01-15 8:47 ` Kent Overstreet
@ 2026-01-15 11:39 ` Greg KH
2026-01-15 11:40 ` Greg KH
0 siblings, 1 reply; 7+ messages in thread
From: Greg KH @ 2026-01-15 11:39 UTC (permalink / raw)
To: Kent Overstreet; +Cc: stable, stable-commits, zhangshida, Coly Li
On Thu, Jan 15, 2026 at 03:47:39AM -0500, Kent Overstreet wrote:
> On Mon, Jan 12, 2026 at 12:23:45PM -0500, Sasha Levin wrote:
> > This is a note to let you know that I've just added the patch titled
> >
> > bcache: fix improper use of bi_end_io
> >
> > to the 6.6-stable tree which can be found at:
> > http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> >
> > The filename of the patch is:
> > bcache-fix-improper-use-of-bi_end_io.patch
> > and it can be found in the queue-6.6 subdirectory.
> >
> > If you, or anyone else, feels it should not be added to the stable tree,
> > please let <stable@vger.kernel.org> know about it.
>
> Sasha, has this been dropped?
Why just drop it from 6.6? What about all other branches? What about
Linus's tree?
thanks,
greg k-h
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: Patch "bcache: fix improper use of bi_end_io" has been added to the 6.6-stable tree
2026-01-15 11:39 ` Greg KH
@ 2026-01-15 11:40 ` Greg KH
0 siblings, 0 replies; 7+ messages in thread
From: Greg KH @ 2026-01-15 11:40 UTC (permalink / raw)
To: Kent Overstreet; +Cc: stable, stable-commits, zhangshida, Coly Li
On Thu, Jan 15, 2026 at 12:39:34PM +0100, Greg KH wrote:
> On Thu, Jan 15, 2026 at 03:47:39AM -0500, Kent Overstreet wrote:
> > On Mon, Jan 12, 2026 at 12:23:45PM -0500, Sasha Levin wrote:
> > > This is a note to let you know that I've just added the patch titled
> > >
> > > bcache: fix improper use of bi_end_io
> > >
> > > to the 6.6-stable tree which can be found at:
> > > http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> > >
> > > The filename of the patch is:
> > > bcache-fix-improper-use-of-bi_end_io.patch
> > > and it can be found in the queue-6.6 subdirectory.
> > >
> > > If you, or anyone else, feels it should not be added to the stable tree,
> > > please let <stable@vger.kernel.org> know about it.
> >
> > Sasha, has this been dropped?
>
> Why just drop it from 6.6? What about all other branches? What about
> Linus's tree?
Ah, it's being reverted there, ok, I'll go drop this from all branches
now, thanks.
greg k-h
^ permalink raw reply [flat|nested] 7+ messages in thread