KMSAN doesn't know about DMA memory writes performed by devices. We unpoison such memory when it's mapped to avoid false positive reports. Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx> --- Link: https://linux-review.googlesource.com/id/Ia162dc4c5a92e74d4686c1be32a4dfeffc5c32cd --- kernel/dma/mapping.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 9478eccd1c8e6..0560080813761 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -156,6 +156,7 @@ dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page, addr = dma_direct_map_page(dev, page, offset, size, dir, attrs); else addr = ops->map_page(dev, page, offset, size, dir, attrs); + kmsan_handle_dma(page, offset, size, dir); debug_dma_map_page(dev, page, offset, size, dir, addr, attrs); return addr; @@ -194,11 +195,13 @@ static int __dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, else ents = ops->map_sg(dev, sg, nents, dir, attrs); - if (ents > 0) + if (ents > 0) { + kmsan_handle_dma_sg(sg, nents, dir); debug_dma_map_sg(dev, sg, nents, ents, dir, attrs); - else if (WARN_ON_ONCE(ents != -EINVAL && ents != -ENOMEM && - ents != -EIO)) + } else if (WARN_ON_ONCE(ents != -EINVAL && ents != -ENOMEM && + ents != -EIO)) { return -EIO; + } return ents; } -- 2.34.1.173.g76aa8bc2d0-goog
