[PATCH 1/5] mm/damon/core: use kvmalloc for target regions array

[SJ Park <sj@kernel.org>]

From: Akinobu Mita <akinobu.mita@gmail.com>

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>
Reviewed-by: SJ Park <sj@kkernel.org>
Signed-off-by: SJ Park <sj@kernel.org>
---
Changes from v1
- v1: https://lore.kernel.org/20260603112306.58490-1-akinobu.mita@gmail.com
- Collect R-b: from SJ.
- Rebase to latest mm-new.

 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 3dd2750c2ef20..ded76719e8a14 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -1362,14 +1362,14 @@ 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;
 }
 
-- 
2.47.3