dma-direct check for highmem pages in dma_direct_alloc_pages
authorChristoph Hellwig <hch@lst.de>
Sat, 26 Sep 2020 14:39:36 +0000 (16:39 +0200)
committerChristoph Hellwig <hch@lst.de>
Wed, 7 Oct 2020 09:03:21 +0000 (11:03 +0200)
Check for highmem pages from CMA, just like in the dma_direct_alloc path.

Signed-off-by: Christoph Hellwig <hch@lst.de>
kernel/dma/direct.c

index bf9f776..f5ecadd 100644 (file)
@@ -309,6 +309,17 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
        page = __dma_direct_alloc_pages(dev, size, gfp);
        if (!page)
                return NULL;
+       if (PageHighMem(page)) {
+               /*
+                * Depending on the cma= arguments and per-arch setup
+                * dma_alloc_contiguous could return highmem pages.
+                * Without remapping there is no way to return them here,
+                * so log an error and fail.
+                */
+               dev_info(dev, "Rejecting highmem page from CMA.\n");
+               goto out_free_pages;
+       }
+
        ret = page_address(page);
        if (force_dma_unencrypted(dev)) {
                if (set_memory_decrypted((unsigned long)ret,