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| author | Sergey Dyasly <dserrg@gmail.com> | 2013-09-24 17:38:00 +0200 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2013-10-29 12:06:03 +0100 |
| commit | 3159f372354e8e1f5dee714663d705dd2c7e0759 (patch) | |
| tree | 6ac30e573a919746517032111272f06061d2f329 /arch/arm/mm/mmap.c | |
| parent | Linux 3.12-rc6 (diff) | |
| download | linux-3159f372354e8e1f5dee714663d705dd2c7e0759.tar.xz linux-3159f372354e8e1f5dee714663d705dd2c7e0759.zip | |
ARM: 7840/1: LPAE: don't reject mapping /dev/mem above 4GB
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>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mm/mmap.c')
| -rw-r--r-- | arch/arm/mm/mmap.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c index 0c6356255fe3..d27158c38eb0 100644 --- a/arch/arm/mm/mmap.c +++ b/arch/arm/mm/mmap.c @@ -202,13 +202,11 @@ 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 |