On ARM, x86_64, sparc64 platform, virt_to_page only convert a _valid_ virtual address to struct page *, virt_addr_valid(x) indicates whether a virtual address is valid. If ptr is point to a static variable in module area, virt_to_page will return a invalid value.
Signed-off-by: lijiazi <[email protected]> --- include/linux/dma-mapping.h | 10 +++++++--- mm/vmalloc.c | 1 + 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 330ad58..37e645d 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -580,9 +580,13 @@ static inline unsigned long dma_get_merge_boundary(struct device *dev) static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr, size_t size, enum dma_data_direction dir, unsigned long attrs) { - /* DMA must never operate on areas that might be remapped. */ - if (dev_WARN_ONCE(dev, is_vmalloc_addr(ptr), - "rejecting DMA map of vmalloc memory\n")) + /* DMA must never operate on areas that might be remapped. + * ARM, X86_64, sparc64 put module in a special place, if ptr + * point to static variable in module area, virt_to_page will + * return err page *. + */ + if (dev_WARN_ONCE(dev, is_vmalloc_or_module_addr(ptr), + "rejecting DMA map of vmalloc or module memory\n")) return DMA_MAPPING_ERROR; debug_dma_map_single(dev, ptr, size); return dma_map_page_attrs(dev, virt_to_page(ptr), offset_in_page(ptr), diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 588303a..71ce6dc 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -262,6 +262,7 @@ int is_vmalloc_or_module_addr(const void *x) #endif return is_vmalloc_addr(x); } +EXPORT_SYMBOL(is_vmalloc_or_module_addr); /* * Walk a vmap address to the struct page it maps. -- 2.7.4 _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
