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| author | Kim Phillips <kim.phillips@linaro.org> | 2014-06-26 01:45:51 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-06-29 12:25:37 -0700 |
| commit | e16bb584be4a6134fe9eb476d358a0aa2fbb5626 (patch) | |
| tree | c9855756919932f5b45579d2f43c65ee583f4e85 | |
| parent | 0aa06a1a546ecada733a2596df60e0665d8ab778 (diff) | |
| download | lwn-e16bb584be4a6134fe9eb476d358a0aa2fbb5626.tar.gz lwn-e16bb584be4a6134fe9eb476d358a0aa2fbb5626.zip | |
ARM: KVM: user_mem_abort: support stage 2 MMIO page mapping
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 <kim.phillips@linaro.org>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/arm/kvm/mmu.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 3d96eced8a12..70ed2c1f57b0 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); } |