From mboxrd@z Thu Jan 1 00:00:00 1970 From: will.deacon@arm.com (Will Deacon) Date: Fri, 20 Dec 2013 17:45:43 +0000 Subject: [PATCHv3] arm: Correct virt_addr_valid In-Reply-To: <1387416724-17868-1-git-send-email-lauraa@codeaurora.org> References: <1387416724-17868-1-git-send-email-lauraa@codeaurora.org> Message-ID: <20131220174543.GJ16829@mudshark.cambridge.arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Dec 19, 2013 at 01:32:04AM +0000, Laura Abbott wrote: > 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: Russell King > Cc: Will Deacon > Cc: Nicolas Pitre > Signed-off-by: Laura Abbott > --- > arch/arm/include/asm/memory.h | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/arch/arm/include/asm/memory.h b/arch/arm/include/asm/memory.h > index 9ecccc8..35a8511 100644 > --- a/arch/arm/include/asm/memory.h > +++ b/arch/arm/include/asm/memory.h > @@ -350,7 +350,8 @@ 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) ) Acked-by: Will Deacon Will