From 13ea55ea20176736516b20b9ea2d8cf97dbe74f5 Mon Sep 17 00:00:00 2001 From: Li Chen Date: Fri, 5 Dec 2025 05:46:20 +0000 Subject: [PATCH] dm pcache: fix segment info indexing Segment info indexing also used sizeof(struct) instead of the 4K metadata stride, so info_index could point between slots and subsequent writes would advance incorrectly. Derive info_index from the pointer returned by the segment meta search using PCACHE_SEG_INFO_SIZE and advance to the next slot for future updates. Signed-off-by: Li Chen Signed-off-by: Dongsheng Yang Signed-off-by: Mikulas Patocka Reviewed-by: Zheng Gu Cc: stable@vger.kernel.org # 6.18 --- drivers/md/dm-pcache/cache_segment.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/md/dm-pcache/cache_segment.c b/drivers/md/dm-pcache/cache_segment.c index ae57cc261422..9d92e2b067ed 100644 --- a/drivers/md/dm-pcache/cache_segment.c +++ b/drivers/md/dm-pcache/cache_segment.c @@ -56,7 +56,10 @@ static int cache_seg_info_load(struct pcache_cache_segment *cache_seg) ret = -EIO; goto out; } - cache_seg->info_index = cache_seg_info_addr - cache_seg_info_addr_base; + + cache_seg->info_index = + ((char *)cache_seg_info_addr - (char *)cache_seg_info_addr_base) / + PCACHE_SEG_INFO_SIZE; out: mutex_unlock(&cache_seg->info_lock); -- 2.47.3