On Mon, Dec 16, 2013 at 07:01:44PM +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 <linux@xxxxxxxxxxxxxxxx> > Cc: Will Deacon <will.deacon@xxxxxxx> > Cc: Nicolas Pitre <nico@xxxxxxxxxx> > Signed-off-by: Laura Abbott <lauraa@xxxxxxxxxxxxxx> > --- > 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..6211df0 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) (pfn_valid(__pa(kaddr) >> PAGE_SHIFT) && \ > + ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)) Can you change the order of the check please, so that we do the quicker lowmem range checks before the pfn_valid check? I know I backed down on the latter being slow, but it's still slower than what we had before and changing the order of the conjunction is easy to do. Cheers, Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/linux-arm-kernel