The padding field in the structure was previously reserved to maintain a stable interface for potential new fields, ensuring compatibility with user-space shared data structures. However,it was accidentally removed by tiantao in a prior commit, which may lead to incompatibility between user space and the kernel.

This patch reinstates the padding to restore the original structure layout and preserve compatibility.

Fixes: 8ddde07a3d28 ("dma-mapping: benchmark: extract a common header file for map_benchmark definition") Cc: stable@vger.kernel.org Acked-by: Barry Song baohua@kernel.org Signed-off-by: Qinxin Xia xiaqinxin@huawei.com --- include/linux/map_benchmark.h | 1 + 1 file changed, 1 insertion(+)

diff --git a/include/linux/map_benchmark.h b/include/linux/map_benchmark.h index 62674c83bde4..48e2ff95332f 100644 --- a/include/linux/map_benchmark.h +++ b/include/linux/map_benchmark.h @@ -27,5 +27,6 @@ struct map_benchmark { __u32 dma_dir; /* DMA data direction */ __u32 dma_trans_ns; /* time for DMA transmission in ns */ __u32 granule; /* how many PAGE_SIZE will do map/unmap once a time */ + __u8 expansion[76]; /* For future use */ }; #endif /* _KERNEL_DMA_BENCHMARK_H */