| Message ID | 1372952185-2553-1-git-send-email-dserrg@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Jul 04, 2013 at 04:36:25PM +0100, Sergey Dyasly wrote: > With LPAE enabled, physical address space is larger than 4GB. Allow mapping any > part of it via /dev/mem by using PHYS_MASK to determine valid range. > > PHYS_MASK covers 40 bits with LPAE enabled and 32 bits otherwise. > > Reported-by: Vassili Karpov <av1474@comtv.ru> > Signed-off-by: Sergey Dyasly <dserrg@gmail.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c index 10062ce..2db5d2d 100644 --- a/arch/arm/mm/mmap.c +++ b/arch/arm/mm/mmap.c @@ -204,13 +204,11 @@ int valid_phys_addr_range(phys_addr_t addr, size_t size) } /* - * We don't use supersection mappings for mmap() on /dev/mem, which - * means that we can't map the memory area above the 4G barrier into - * userspace. + * Do not allow /dev/mem mappings beyond the supported physical range. */ int valid_mmap_phys_addr_range(unsigned long pfn, size_t size) { - return !(pfn + (size >> PAGE_SHIFT) > 0x00100000); + return (pfn + (size >> PAGE_SHIFT)) <= (1 + (PHYS_MASK >> PAGE_SHIFT)); } #ifdef CONFIG_STRICT_DEVMEM
With LPAE enabled, physical address space is larger than 4GB. Allow mapping any part of it via /dev/mem by using PHYS_MASK to determine valid range. PHYS_MASK covers 40 bits with LPAE enabled and 32 bits otherwise. Reported-by: Vassili Karpov <av1474@comtv.ru> Signed-off-by: Sergey Dyasly <dserrg@gmail.com> --- v3: - Fixed 32-bit overflow v2: - Removed #ifdef and changed original function arch/arm/mm/mmap.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)