From: Boris Ostrovsky boris.ostrovsky@oracle.com
[ Upstream commit 8b1e868f66076490189a36d984fcce286cdd6295 ]
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 boris.ostrovsky@oracle.com Signed-off-by: Stefano Stabellini stefano.stabellini@xilinx.com Reviewed-by: Boris Ostrovsky boris.ostrovsky@oracle.com Tested-by: Corey Minyard cminyard@mvista.com Tested-by: Roman Shaposhnik roman@zededa.com Link: https://lore.kernel.org/r/20200710223427.6897-1-sstabellini@kernel.org Signed-off-by: Juergen Gross jgross@suse.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 b6d27762c6f8c..5fbadd07819bd 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);