From mboxrd@z Thu Jan 1 00:00:00 1970 From: mark.rutland@arm.com (Mark Rutland) Date: Fri, 20 Nov 2015 15:35:24 +0000 Subject: [PATCH 2/2] arm64: mm: allow sections for unaligned bases In-Reply-To: <1448033724-13846-1-git-send-email-mark.rutland@arm.com> References: <1448033724-13846-1-git-send-email-mark.rutland@arm.com> Message-ID: <1448033724-13846-2-git-send-email-mark.rutland@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 Cc: Ard Biesheuvel Cc: Catalin Marinas Cc: Laura Abbott Cc: Steve Capper Cc: Will Deacon --- arch/arm64/mm/mmu.c | 1 + 1 file changed, 1 insertion(+) 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