Re: [PATCH AUTOSEL 4.20 42/77] dm: fix clone_bio() to trigger blk_recount_segments()

From: Mike Snitzer
Date: Thu Feb 14 2019 - 22:49:13 EST

On Thu, Feb 14 2019 at 9:08pm -0500,
Sasha Levin <sashal@xxxxxxxxxx> wrote:

> From: Mike Snitzer <snitzer@xxxxxxxxxx>
> [ Upstream commit 57c36519e4b949f89381053f7283f5d605595b42 ]
> DM's clone_bio() now benefits from using bio_trim() by fixing the fact
> that clone_bio() wasn't clearing BIO_SEG_VALID like bio_trim() does;
> which triggers blk_recount_segments() via bio_phys_segments().
> Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx>
> Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

Please no, I later effectively reverted this change with commit
fa8db4948f522 ("dm: don't use bio_trim() afterall")

(As and aside, I really shouldn't have to defend against stable@ bots
picking up a commit, like 57c36519e4b949f, that wasn't marked for