From 776617db78c6d208780e7c69d4d68d1fa82913de Mon Sep 17 00:00:00 2001 From: Tobias Holl Date: Wed, 3 May 2023 08:59:50 -0600 Subject: [PATCH] io_uring/rsrc: check for nonconsecutive pages Pages that are from the same folio do not necessarily need to be consecutive. In that case, we cannot consolidate them into a single bvec entry. Before applying the huge page optimization from commit 57bebf807e2a ("io_uring/rsrc: optimise registered huge pages"), check that the memory is actually consecutive. Cc: stable@vger.kernel.org Fixes: 57bebf807e2a ("io_uring/rsrc: optimise registered huge pages") Signed-off-by: Tobias Holl [axboe: formatting] Signed-off-by: Jens Axboe --- io_uring/rsrc.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c index ddee7adb4006..00affcf811ad 100644 --- a/io_uring/rsrc.c +++ b/io_uring/rsrc.c @@ -1117,7 +1117,12 @@ static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, if (nr_pages > 1) { folio = page_folio(pages[0]); for (i = 1; i < nr_pages; i++) { - if (page_folio(pages[i]) != folio) { + /* + * Pages must be consecutive and on the same folio for + * this to work + */ + if (page_folio(pages[i]) != folio || + pages[i] != pages[i - 1] + 1) { folio = NULL; break; }