From: Haimin Zhang <tcs.kernel@xxxxxxxxx> commit cc8f7fe1f5eab010191aa4570f27641876fa1267 upstream. Add __GFP_ZERO flag for alloc_page in function bio_copy_kern to initialize the buffer of a bio. Signed-off-by: Haimin Zhang <tcs.kernel@xxxxxxxxx> Reviewed-by: Chaitanya Kulkarni <kch@xxxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Link: https://lore.kernel.org/r/20220216084038.15635-1-tcs.kernel@xxxxxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> [DP: Backported to 4.19: Manually added __GFP_ZERO flag] Signed-off-by: Dragos-Marian Panait <dragos.panait@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- block/bio.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/block/bio.c +++ b/block/bio.c @@ -1538,7 +1538,7 @@ struct bio *bio_copy_kern(struct request if (bytes > len) bytes = len; - page = alloc_page(q->bounce_gfp | gfp_mask); + page = alloc_page(q->bounce_gfp | __GFP_ZERO | gfp_mask); if (!page) goto cleanup;