From: Qinxin Xia Date: Tue, 28 Oct 2025 12:08:59 +0000 (+0800) Subject: dma-mapping: benchmark: Restore padding to ensure uABI remained consistent X-Git-Tag: v6.18-rc6~35^2~1 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=23ee8a2563a0f24cf4964685ced23c32be444ab8;p=thirdparty%2Flinux.git dma-mapping: benchmark: Restore padding to ensure uABI remained consistent 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 Signed-off-by: Qinxin Xia Reported-by: Barry Song Closes: https://lore.kernel.org/lkml/CAGsJ_4waiZ2+NBJG+SCnbNk+nQ_ZF13_Q5FHJqZyxyJTcEop2A@mail.gmail.com/ Reviewed-by: Jonathan Cameron Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/20251028120900.2265511-2-xiaqinxin@huawei.com --- 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 */