On 7/1/19 1:14 AM, Ming Lei wrote:
> 'bio->bi_iter.bi_size' is 'unsigned int', which at most hold 4G - 1
> bytes.
>
> Before 07173c3ec276 ("block: enable multipage bvecs"), one bio can
> include very limited pages, and usually at most 256, so the fs bio
> size won't be bigger than 1M bytes most of times.
>
> Since we support multi-page bvec, in theory one fs bio really can
> be added > 1M pages, especially in case of hugepage, or big writeback
> with too many dirty pages. Then there is chance in which .bi_size
> is overflowed.
>
> Fixes this issue by using bio_full() to check if the added segment may
> overflow .bi_size.
Any objections to queuing this up for 5.3? It's not a new regression
this series.
--
Jens Axboe
