[PATCH 2/2] ARM: KVM: user_mem_abort: support stage 2 MMIO page mapping

From: Kim Phillips
Date: Tue Mar 25 2014 - 18:08:56 EST


Use the correct memory type for device MMIO mappings: PAGE_S2_DEVICE.

Signed-off-by: Kim Phillips <kim.phillips@xxxxxxxxxx>
---
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 7789857..a354610 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -652,6 +652,7 @@ 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) {
@@ -702,6 +703,9 @@ 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;
@@ -709,7 +713,7 @@ 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);
@@ -718,13 +722,14 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
coherent_icache_guest_page(kvm, 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_icache_guest_page(kvm, 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);
}


--
1.9.1

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