From: Xuelin Shi <[email protected]> This patch does NOT apply to the 3.12 stable tree. If you still want it applied, please provide a backport.
=============== commit c1f43dd9c20d85e66c4d77e284f64ac114abe3f8 upstream. The count which is used to get_unmap_data maybe not the same as the count computed in dmaengine_unmap which causes to free data in a wrong pool. This patch fixes this issue by keeping the map count with unmap_data structure and use this count to get the pool. Cc: <[email protected]> Signed-off-by: Xuelin Shi <[email protected]> Signed-off-by: Dan Williams <[email protected]> --- drivers/dma/dmaengine.c | 2 ++ include/linux/dmaengine.h | 1 + 2 files changed, 3 insertions(+) diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index a886713937fd..d5d30ed863ce 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -1009,6 +1009,7 @@ static void dmaengine_unmap(struct kref *kref) dma_unmap_page(dev, unmap->addr[i], unmap->len, DMA_BIDIRECTIONAL); } + cnt = unmap->map_cnt; mempool_free(unmap, __get_unmap_pool(cnt)->pool); } @@ -1074,6 +1075,7 @@ dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags) memset(unmap, 0, sizeof(*unmap)); kref_init(&unmap->kref); unmap->dev = dev; + unmap->map_cnt = nr; return unmap; } diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 8300fb87b84a..72cb0ddb9678 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -429,6 +429,7 @@ typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param); typedef void (*dma_async_tx_callback)(void *dma_async_param); struct dmaengine_unmap_data { + u8 map_cnt; u8 to_cnt; u8 from_cnt; u8 bidi_cnt; -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
