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charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, Jul 24, 2025 at 4:56=E2=80=AFPM Qinxin Xia w= rote: > > 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 fil= e for map_benchmark definition") > Cc: stable@vger.kernel.org > Acked-by: Barry Song > Signed-off-by: Qinxin Xia I don=E2=80=99t think these two patches should be part of the same series. = This one is a bug fix and should be handled separately=E2=80=94ideally picked up= on its own and backported to stable. Also, the subject should not say "Add"=E2=80=94it should be "Restore". I as= sume Marek can handle it? > --- > 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..2ac2fe52f248 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 ti= me */ > + __u8 expansion[76]; /* For future use */ > }; > #endif /* _KERNEL_DMA_BENCHMARK_H */ > -- > 2.33.0 > Thanks Barry