Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161176AbbEVJcL (ORCPT ); Fri, 22 May 2015 05:32:11 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:34971 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757062AbbEVI7T (ORCPT ); Fri, 22 May 2015 04:59:19 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Kim Phillips , Marc Zyngier , Shannon Zhao , Luis Henriques Subject: [PATCH 3.16.y-ckt 042/129] ARM: KVM: user_mem_abort: support stage 2 MMIO page mapping Date: Fri, 22 May 2015 09:57:07 +0100 Message-Id: <1432285114-9254-43-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1432285114-9254-1-git-send-email-luis.henriques@canonical.com> References: <1432285114-9254-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2959 Lines: 78 3.16.7-ckt12 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Kim Phillips commit b88657674d39fc2127d62d0de9ca142e166443c8 upstream. A userspace process can map device MMIO memory via VFIO or /dev/mem, e.g., for platform device passthrough support in QEMU. During early development, we found the PAGE_S2 memory type being used for MMIO mappings. This patch corrects that by using the more strongly ordered memory type for device MMIO mappings: PAGE_S2_DEVICE. Signed-off-by: Kim Phillips Acked-by: Christoffer Dall Acked-by: Will Deacon Signed-off-by: Marc Zyngier Signed-off-by: Shannon Zhao Signed-off-by: Luis Henriques --- arch/arm/kvm/mmu.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index b2a708be1407..16e7994bf347 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -759,6 +759,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache; struct vm_area_struct *vma; pfn_t pfn; + pgprot_t mem_type = PAGE_S2; write_fault = kvm_is_write_fault(kvm_vcpu_get_hsr(vcpu)); if (fault_status == FSC_PERM && !write_fault) { @@ -809,6 +810,9 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, if (is_error_pfn(pfn)) return -EFAULT; + if (kvm_is_mmio_pfn(pfn)) + mem_type = PAGE_S2_DEVICE; + spin_lock(&kvm->mmu_lock); if (mmu_notifier_retry(kvm, mmu_seq)) goto out_unlock; @@ -816,7 +820,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, hugetlb = transparent_hugepage_adjust(&pfn, &fault_ipa); if (hugetlb) { - pmd_t new_pmd = pfn_pmd(pfn, PAGE_S2); + pmd_t new_pmd = pfn_pmd(pfn, mem_type); new_pmd = pmd_mkhuge(new_pmd); if (writable) { kvm_set_s2pmd_writable(&new_pmd); @@ -825,13 +829,14 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, coherent_cache_guest_page(vcpu, hva & PMD_MASK, PMD_SIZE); ret = stage2_set_pmd_huge(kvm, memcache, fault_ipa, &new_pmd); } else { - pte_t new_pte = pfn_pte(pfn, PAGE_S2); + pte_t new_pte = pfn_pte(pfn, mem_type); if (writable) { kvm_set_s2pte_writable(&new_pte); kvm_set_pfn_dirty(pfn); } coherent_cache_guest_page(vcpu, hva, PAGE_SIZE); - ret = stage2_set_pte(kvm, memcache, fault_ipa, &new_pte, false); + ret = stage2_set_pte(kvm, memcache, fault_ipa, &new_pte, + mem_type == PAGE_S2_DEVICE); } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/