This is a note to let you know that I've just added the patch titled
block: Fix page refcounts for unaligned buffers in __bio_release_pages()
to the 6.1-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:
block-fix-page-refcounts-for-unaligned-buffers-in-__bio_release_pages.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 38b43539d64b2fa020b3b9a752a986769f87f7a6 Mon Sep 17 00:00:00 2001
From: Tony Battersby <tonyb@xxxxxxxxxxxxxxx>
Date: Thu, 29 Feb 2024 13:08:09 -0500
Subject: block: Fix page refcounts for unaligned buffers in __bio_release_pages()
From: Tony Battersby <tonyb@xxxxxxxxxxxxxxx>
commit 38b43539d64b2fa020b3b9a752a986769f87f7a6 upstream.
Fix an incorrect number of pages being released for buffers that do not
start at the beginning of a page.
Fixes: 1b151e2435fc ("block: Remove special-casing of compound pages")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Tony Battersby <tonyb@xxxxxxxxxxxxxxx>
Tested-by: Greg Edwards <gedwards@xxxxxxx>
Link: https://lore.kernel.org/r/86e592a9-98d4-4cff-a646-0c0084328356@xxxxxxxxxxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
[ Tony: backport to v6.1 by replacing bio_release_page() loop with
folio_put_refs() as commits fd363244e883 and e4cc64657bec are not
present. ]
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
block/bio.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)
--- a/block/bio.c
+++ b/block/bio.c
@@ -1112,19 +1112,16 @@ void __bio_release_pages(struct bio *bio
struct folio_iter fi;
bio_for_each_folio_all(fi, bio) {
- struct page *page;
- size_t done = 0;
+ size_t nr_pages;
if (mark_dirty) {
folio_lock(fi.folio);
folio_mark_dirty(fi.folio);
folio_unlock(fi.folio);
}
- page = folio_page(fi.folio, fi.offset / PAGE_SIZE);
- do {
- folio_put(fi.folio);
- done += PAGE_SIZE;
- } while (done < fi.length);
+ nr_pages = (fi.offset + fi.length - 1) / PAGE_SIZE -
+ fi.offset / PAGE_SIZE + 1;
+ folio_put_refs(fi.folio, nr_pages);
}
}
EXPORT_SYMBOL_GPL(__bio_release_pages);
Patches currently in stable-queue which might be from tonyb@xxxxxxxxxxxxxxx are
queue-6.1/block-fix-page-refcounts-for-unaligned-buffers-in-__bio_release_pages.patch
