This is a note to let you know that I've just added the patch titled
io_uring/rsrc: check for nonconsecutive pages
to the 6.3-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
io_uring-rsrc-check-for-nonconsecutive-pages.patch
and it can be found in the queue-6.3 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 776617db78c6d208780e7c69d4d68d1fa82913de Mon Sep 17 00:00:00 2001
From: Tobias Holl <tobias@xxxxxxxxx>
Date: Wed, 3 May 2023 08:59:50 -0600
Subject: io_uring/rsrc: check for nonconsecutive pages
From: Tobias Holl <tobias@xxxxxxxxx>
commit 776617db78c6d208780e7c69d4d68d1fa82913de upstream.
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@xxxxxxxxxxxxxxx
Fixes: 57bebf807e2a ("io_uring/rsrc: optimise registered huge pages")
Signed-off-by: Tobias Holl <tobias@xxxxxxxxx>
[axboe: formatting]
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
io_uring/rsrc.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/io_uring/rsrc.c
+++ b/io_uring/rsrc.c
@@ -1230,7 +1230,12 @@ static int io_sqe_buffer_register(struct
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;
}
Patches currently in stable-queue which might be from tobias@xxxxxxxxx are
queue-6.3/io_uring-rsrc-check-for-nonconsecutive-pages.patch
