3.3-stable review patch. If anyone has any objections, please let me know.
------------------ From: Bernd Schubert <[email protected]> commit f908ee9463b09ddd05e1c1a0111132212dc05fac upstream. The number of bio_get_nr_vecs() is passed down via bio_alloc() to bvec_alloc_bs(), which fails the bio allocation if nr_iovecs > BIO_MAX_PAGES. For the underlying caller this causes an unexpected bio allocation failure. Limiting to queue_max_segments() is not sufficient, as max_segments also might be very large. bvec_alloc_bs(gfp_mask, nr_iovecs, ) => NULL when nr_iovecs > BIO_MAX_PAGES bio_alloc_bioset(gfp_mask, nr_iovecs, ...) bio_alloc(GFP_NOIO, nvecs) xfs_alloc_ioend_bio() Signed-off-by: Bernd Schubert <[email protected]> Signed-off-by: Jens Axboe <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- fs/bio.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/fs/bio.c +++ b/fs/bio.c @@ -505,9 +505,14 @@ EXPORT_SYMBOL(bio_clone); int bio_get_nr_vecs(struct block_device *bdev) { struct request_queue *q = bdev_get_queue(bdev); - return min_t(unsigned, + int nr_pages; + + nr_pages = min_t(unsigned, queue_max_segments(q), queue_max_sectors(q) / (PAGE_SIZE >> 9) + 1); + + return min_t(unsigned, nr_pages, BIO_MAX_PAGES); + } EXPORT_SYMBOL(bio_get_nr_vecs); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
