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| author | Nicolin Chen <nicoleotsuka@gmail.com> | 2019-07-26 12:34:32 -0700 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2019-07-29 09:50:04 +0300 |
| commit | c6622a425acd1d2f3a443cd39b490a8777b622d7 (patch) | |
| tree | a3a9ea952c439bf74ee1a243ffc3a6f73e4a3a9b /kernel | |
| parent | 609488bc979f99f805f34e9a32c1e3b71179d10b (diff) | |
| download | lwn-c6622a425acd1d2f3a443cd39b490a8777b622d7.tar.gz lwn-c6622a425acd1d2f3a443cd39b490a8777b622d7.zip | |
dma-contiguous: do not overwrite align in dma_alloc_contiguous()
The dma_alloc_contiguous() limits align at CONFIG_CMA_ALIGNMENT for
cma_alloc() however it does not restore it for the fallback routine.
This will result in a size mismatch between the allocation and free
when running into the fallback routines after cma_alloc() fails, if
the align is larger than CONFIG_CMA_ALIGNMENT.
This patch adds a cma_align to take care of cma_alloc() and prevent
the align from being overwritten.
Fixes: fdaeec198ada ("dma-contiguous: add dma_{alloc,free}_contiguous() helpers")
Reported-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/dma/contiguous.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c index bfc0c17f2a3d..ea8259f53eda 100644 --- a/kernel/dma/contiguous.c +++ b/kernel/dma/contiguous.c @@ -243,8 +243,9 @@ struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp) /* CMA can be used only in the context which permits sleeping */ if (cma && gfpflags_allow_blocking(gfp)) { - align = min_t(size_t, align, CONFIG_CMA_ALIGNMENT); - page = cma_alloc(cma, count, align, gfp & __GFP_NOWARN); + size_t cma_align = min_t(size_t, align, CONFIG_CMA_ALIGNMENT); + + page = cma_alloc(cma, count, cma_align, gfp & __GFP_NOWARN); } /* Fallback allocation of normal pages */ |