From: Christoph Hellwig <hch@lst.de>
Date: Sat, 26 Sep 2020 14:39:36 +0000 (+0200)
Subject: dma-direct check for highmem pages in dma_direct_alloc_pages
X-Git-Tag: v5.10-rc1~120^2~3
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=08a89c28304ae74e4c7422f784359e41a37e3e7c;p=thirdparty%2Fkernel%2Flinux.git

dma-direct check for highmem pages in dma_direct_alloc_pages

Check for highmem pages from CMA, just like in the dma_direct_alloc path.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---

diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index bf9f77623022b..f5ecadd4e1c16 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -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,