Tested-by: Pavel Fedin <p.fedin@xxxxxxxxxxx> Kind regards, Pavel Fedin Expert Engineer Samsung Electronics Research center Russia > -----Original Message----- > From: Ard Biesheuvel [mailto:ard.biesheuvel@xxxxxxxxxx] > Sent: Thursday, December 03, 2015 11:25 AM > To: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; kvmarm@xxxxxxxxxxxxxxxxxxxxx; > christoffer.dall@xxxxxxxxxx; p.fedin@xxxxxxxxxxx > Cc: Ard Biesheuvel > Subject: [PATCH v2] ARM/arm64: KVM: correct PTE uncachedness check > > 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") > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> > --- > arch/arm/kvm/mmu.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c > index 7dace909d5cf..61d96a645ff3 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); > } > -- > 1.9.1 _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
