From 8b1e868f66076490189a36d984fcce286cdd6295 Mon Sep 17 00:00:00 2001 From: Boris Ostrovsky Date: Fri, 10 Jul 2020 15:34:17 -0700 Subject: [PATCH] swiotlb-xen: use vmalloc_to_page on vmalloc virt addresses xen_alloc_coherent_pages might return pages for which virt_to_phys and virt_to_page don't work, e.g. ioremap'ed pages. So in xen_swiotlb_free_coherent we can't assume that virt_to_page works. Instead add a is_vmalloc_addr check and use vmalloc_to_page on vmalloc virt addresses. This patch fixes the following crash at boot on RPi4 (the underlying issue is not RPi4 specific): https://marc.info/?l=xen-devel&m=158862573216800 Signed-off-by: Boris Ostrovsky Signed-off-by: Stefano Stabellini Reviewed-by: Boris Ostrovsky Tested-by: Corey Minyard Tested-by: Roman Shaposhnik Link: https://lore.kernel.org/r/20200710223427.6897-1-sstabellini@kernel.org Signed-off-by: Juergen Gross --- drivers/xen/swiotlb-xen.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index b6d2776..5fbadd0 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -335,6 +335,7 @@ xen_swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr, int order = get_order(size); phys_addr_t phys; u64 dma_mask = DMA_BIT_MASK(32); + struct page *page; if (hwdev && hwdev->coherent_dma_mask) dma_mask = hwdev->coherent_dma_mask; @@ -346,9 +347,14 @@ xen_swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr, /* Convert the size to actually allocated. */ size = 1UL << (order + XEN_PAGE_SHIFT); + if (is_vmalloc_addr(vaddr)) + page = vmalloc_to_page(vaddr); + else + page = virt_to_page(vaddr); + if (!WARN_ON((dev_addr + size - 1 > dma_mask) || range_straddles_page_boundary(phys, size)) && - TestClearPageXenRemapped(virt_to_page(vaddr))) + TestClearPageXenRemapped(page)) xen_destroy_contiguous_region(phys, order); xen_free_coherent_pages(hwdev, size, vaddr, (dma_addr_t)phys, attrs); -- 2.7.4