This is a note to let you know that I've just added the patch titled
mm: Account dirty folios properly during splits
to the 5.19-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:
mm-account-dirty-folios-properly-during-splits.patch
and it can be found in the queue-5.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 2440fb7182cde1a88a207a47584146fd8264e4ff
Author: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Date: Tue Jun 28 20:15:29 2022 -0400
mm: Account dirty folios properly during splits
[ Upstream commit fb5c2029f8221e904e604938171c4a8ef169aadb ]
If the last folio in a file is split as a result of truncation,
we simply clear the dirty bits for the pages we're discarding.
That causes NR_FILE_DIRTY (among other counters) to be thrown off
and eventually Linux will hang in balance_dirty_pages_ratelimited()
Reported-by: Dave Chinner <dchinner@xxxxxxxxxx>
Tested-by: Dave Chinner <dchinner@xxxxxxxxxx>
Tested-by: Darrick J. Wong <djwong@xxxxxxxxxx>
Fixes: d68eccad3706 ("mm/filemap: Allow large folios to be added to the page cache")
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 834f288b3769..15965084816d 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -18,6 +18,7 @@
#include <linux/shrinker.h>
#include <linux/mm_inline.h>
#include <linux/swapops.h>
+#include <linux/backing-dev.h>
#include <linux/dax.h>
#include <linux/khugepaged.h>
#include <linux/freezer.h>
@@ -2440,11 +2441,15 @@ static void __split_huge_page(struct page *page, struct list_head *list,
__split_huge_page_tail(head, i, lruvec, list);
/* Some pages can be beyond EOF: drop them from page cache */
if (head[i].index >= end) {
- ClearPageDirty(head + i);
- __delete_from_page_cache(head + i, NULL);
+ struct folio *tail = page_folio(head + i);
+
if (shmem_mapping(head->mapping))
shmem_uncharge(head->mapping->host, 1);
- put_page(head + i);
+ else if (folio_test_clear_dirty(tail))
+ folio_account_cleaned(tail,
+ inode_to_wb(folio->mapping->host));
+ __filemap_remove_folio(tail, NULL);
+ folio_put(tail);
} else if (!PageAnon(page)) {
__xa_store(&head->mapping->i_pages, head[i].index,
head + i, 0);
