From 426bfb6a778411df0245373aa0979ce11d8fff85 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Thu, 3 Dec 2015 09:25:22 +0100 Subject: ARM/arm64: KVM: correct PTE uncachedness check commit 0de58f852875a0f0dcfb120bb8433e4e73c7803b upstream. Commit e6fab5442345 ("ARM/arm64: KVM: test properly for a PTE's uncachedness") modified the logic to test whether a HYP or stage-2 mapping needs flushing, from [incorrectly] interpreting the page table attributes to [incorrectly] checking whether the PFN that backs the mapping is covered by host system RAM. The PFN number is part of the output of the translation, not the input, so we have to use pte_pfn() on the contents of the PTE, not __phys_to_pfn() on the HYP virtual address or stage-2 intermediate physical address. Fixes: e6fab5442345 ("ARM/arm64: KVM: test properly for a PTE's uncachedness") Tested-by: Pavel Fedin Signed-off-by: Ard Biesheuvel Signed-off-by: Marc Zyngier Signed-off-by: Greg Kroah-Hartman --- arch/arm/kvm/mmu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch') diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 49ef4451e893..da09ddcfcc00 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -218,7 +218,7 @@ static void unmap_ptes(struct kvm *kvm, pmd_t *pmd, kvm_tlb_flush_vmid_ipa(kvm, addr); /* No need to invalidate the cache for device mappings */ - if (!kvm_is_device_pfn(__phys_to_pfn(addr))) + if (!kvm_is_device_pfn(pte_pfn(old_pte))) kvm_flush_dcache_pte(old_pte); put_page(virt_to_page(pte)); @@ -310,7 +310,7 @@ static void stage2_flush_ptes(struct kvm *kvm, pmd_t *pmd, pte = pte_offset_kernel(pmd, addr); do { - if (!pte_none(*pte) && !kvm_is_device_pfn(__phys_to_pfn(addr))) + if (!pte_none(*pte) && !kvm_is_device_pfn(pte_pfn(*pte))) kvm_flush_dcache_pte(*pte); } while (pte++, addr += PAGE_SIZE, addr != end); } -- cgit v1.2.3