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From: Akinobu Mita <akinobu.mita@gmail.com>
To: damon@lists.linux.dev
Cc: akinobu.mita@gmail.com
Subject: [PATCH] mm/damon/core: use kvmalloc for target regions array
Date: Wed,  3 Jun 2026 20:23:06 +0900	[thread overview]
Message-ID: <20260603112306.58490-1-akinobu.mita@gmail.com> (raw)

damon_commit_target_regions() temporarily allocates a single contiguous
memory region using kmalloc to store copies of all damon_regions of the
damon_target.
However, if the damon_target has a large number of damon_regions, the
total size may exceed KMALLOC_MAX_SIZE.

This problem can be avoided by using kvmalloc instead of kmalloc.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
---
 mm/damon/core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/damon/core.c b/mm/damon/core.c
index 265d51ade25b..08e5ce53a7b8 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -1358,14 +1358,14 @@ static int damon_commit_target_regions(struct damon_target *dst,
 	if (!i)
 		return 0;
 
-	ranges = kmalloc_objs(*ranges, i, GFP_KERNEL | __GFP_NOWARN);
+	ranges = kvmalloc_objs(*ranges, i, GFP_KERNEL | __GFP_NOWARN);
 	if (!ranges)
 		return -ENOMEM;
 	i = 0;
 	damon_for_each_region(src_region, src)
 		ranges[i++] = src_region->ar;
 	err = damon_set_regions(dst, ranges, i, src_min_region_sz);
-	kfree(ranges);
+	kvfree(ranges);
 	return err;
 }
 
-- 
2.43.0


             reply	other threads:[~2026-06-03 11:23 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-06-03 11:23 Akinobu Mita [this message]
2026-06-03 13:49 ` [PATCH] mm/damon/core: use kvmalloc for target regions array SeongJae Park

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