| From | Jiri Slaby <> | Subject | [PATCH 3.12 109/155] ARM: 7931/1: Correct virt_addr_valid | Date | Tue, 7 Apr 2015 14:51:18 +0200 |
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From: Laura Abbott <lauraa@codeaurora.org>
3.12-stable review patch. If anyone has any objections, please let me know.
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commit efea3403d4b7c6d1dd5d5ac3234c161e8b314d66 upstream.
The definition of virt_addr_valid is that virt_addr_valid should return true if and only if virt_to_page returns a valid pointer. The current definition of virt_addr_valid only checks against the virtual address range. There's no guarantee that just because a virtual address falls bewteen PAGE_OFFSET and high_memory the associated physical memory has a valid backing struct page. Follow the example of other architectures and convert to pfn_valid to verify that the virtual address is actually valid. The check for an address between PAGE_OFFSET and high_memory is still necessary as vmalloc/highmem addresses are not valid with virt_to_page.
Cc: Will Deacon <will.deacon@arm.com> Cc: Nicolas Pitre <nico@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Jiri Slaby <jslaby@suse.cz> --- arch/arm/include/asm/memory.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/arm/include/asm/memory.h b/arch/arm/include/asm/memory.h index e750a938fd3c..152b8e67f8b8 100644 --- a/arch/arm/include/asm/memory.h +++ b/arch/arm/include/asm/memory.h @@ -285,7 +285,8 @@ static inline __deprecated void *bus_to_virt(unsigned long x) #define ARCH_PFN_OFFSET PHYS_PFN_OFFSET #define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT) -#define virt_addr_valid(kaddr) ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory) +#define virt_addr_valid(kaddr) (((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory) \ + && pfn_valid(__pa(kaddr) >> PAGE_SHIFT) ) #endif -- 2.3.4
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