[PATCH] dma-debug: fix physical address retrieval in debug_dma_sync_sg_for_device

From: lirongqing

Date: Wed Jun 03 2026 - 08:43:37 EST


From: Li RongQing <lirongqing@xxxxxxxxx>

In debug_dma_sync_sg_for_device(), when iterating over a scatterlist,
the debug entry population mistakenly uses the head of the scatterlist
'sg' to fetch the physical address via sg_phys(), instead of using the
current iterator variable 's'.

This causes dma-debug to track the physical address of the very first
scatterlist entry for all subsequent entries in the list.

Fix this by passing the correct loop iterator 's' to sg_phys()

Fixes: 9d4f645a1fd49ee ("dma-debug: store a phys_addr_t in struct dma_debug_entry")
Signed-off-by: Li RongQing <lirongqing@xxxxxxxxx>
---
kernel/dma/debug.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c
index 3248f8b..2c0e2cd 100644
--- a/kernel/dma/debug.c
+++ b/kernel/dma/debug.c
@@ -1556,7 +1556,7 @@ void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
struct dma_debug_entry ref = {
.type = dma_debug_sg,
.dev = dev,
- .paddr = sg_phys(sg),
+ .paddr = sg_phys(s),
.dev_addr = sg_dma_address(s),
.size = sg_dma_len(s),
.direction = direction,
--
2.9.4