| Message ID | 1448033724-13846-2-git-send-email-mark.rutland@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 20 November 2015 at 16:35, Mark Rutland <mark.rutland@arm.com> wrote: > Callees of __create_mapping may decide to create section mappings if > sufficient low bits of the physical and virtual addresses they were > passed are zero. While __create_mapping rounds the virtual base address > down, it does not similarly round the phyiscal base address down, and > hence non-zero bits in the physical address can prevent use of a section > mapping, even where a whole next-level table would be used instead. > > Round down the physical base address in __create_mapping to enable all > callees to always create section mappings when such a mapping is > possible. > > Signed-off-by: Mark Rutland <mark.rutland@arm.com> > Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: Laura Abbott <labbott@fedoraproject.org> > Cc: Steve Capper <steve.capper@linaro.org> > Cc: Will Deacon <will.deacon@arm.com> > --- > arch/arm64/mm/mmu.c | 1 + > 1 file changed, 1 insertion(+) > Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> > diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c > index 3b06afa..6467d57 100644 > --- a/arch/arm64/mm/mmu.c > +++ b/arch/arm64/mm/mmu.c > @@ -307,6 +307,7 @@ static void __create_mapping(struct mm_struct *mm, pgd_t *pgd, > if (WARN_ON((phys ^ virt) & ~PAGE_MASK)) > return; > > + phys &= PAGE_MASK; > addr = virt & PAGE_MASK; > length = PAGE_ALIGN(size + (virt & ~PAGE_MASK)); > > -- > 1.9.1 >
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 3b06afa..6467d57 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -307,6 +307,7 @@ static void __create_mapping(struct mm_struct *mm, pgd_t *pgd, if (WARN_ON((phys ^ virt) & ~PAGE_MASK)) return; + phys &= PAGE_MASK; addr = virt & PAGE_MASK; length = PAGE_ALIGN(size + (virt & ~PAGE_MASK));
Callees of __create_mapping may decide to create section mappings if sufficient low bits of the physical and virtual addresses they were passed are zero. While __create_mapping rounds the virtual base address down, it does not similarly round the phyiscal base address down, and hence non-zero bits in the physical address can prevent use of a section mapping, even where a whole next-level table would be used instead. Round down the physical base address in __create_mapping to enable all callees to always create section mappings when such a mapping is possible. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Laura Abbott <labbott@fedoraproject.org> Cc: Steve Capper <steve.capper@linaro.org> Cc: Will Deacon <will.deacon@arm.com> --- arch/arm64/mm/mmu.c | 1 + 1 file changed, 1 insertion(+)