Return -EFAULT from user_mem_abort when the memslot flag is enabled and
fast GUP fails to find a present mapping for the page.
Signed-off-by: Anish Moorthy <amoorthy@xxxxxxxxxx>
---
Documentation/virt/kvm/api.rst | 2 +-
arch/arm64/kvm/arm.c | 1 +
arch/arm64/kvm/mmu.c | 16 +++++++++++++++-
3 files changed, 17 insertions(+), 2 deletions(-)
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index aa7b4024fd41..8a1205f7c271 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -7783,7 +7783,7 @@ bugs and reported to the maintainers so that annotations can be added.
7.35 KVM_CAP_NOWAIT_ON_FAULT
----------------------------
-:Architectures: x86
+:Architectures: x86, arm64
:Returns: -EINVAL.
The presence of this capability indicates that userspace may pass the
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index b34cf0cedffa..46a09c4db901 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -235,6 +235,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
case KVM_CAP_IRQFD_RESAMPLE:
case KVM_CAP_COUNTER_OFFSET:
case KVM_CAP_MEMORY_FAULT_INFO:
+ case KVM_CAP_NOWAIT_ON_FAULT:
r = 1;
break;
case KVM_CAP_SET_GUEST_DEBUG2:
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 3b9d4d24c361..5451b712b0ac 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -1232,6 +1232,8 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
long vma_pagesize, fault_granule;
enum kvm_pgtable_prot prot = KVM_PGTABLE_PROT_R;
struct kvm_pgtable *pgt;
+ bool exit_on_memory_fault = kvm_slot_nowait_on_fault(memslot);
+ uint64_t memory_fault_flags;
fault_granule = 1UL << ARM64_HW_PGTABLE_LEVEL_SHIFT(fault_level);
write_fault = kvm_is_write_fault(vcpu);
@@ -1325,8 +1327,20 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
mmu_seq = vcpu->kvm->mmu_invalidate_seq;
mmap_read_unlock(current->mm);
- pfn = __gfn_to_pfn_memslot(memslot, gfn, false, false, NULL,
+ pfn = __gfn_to_pfn_memslot(memslot, gfn, exit_on_memory_fault, false, NULL,
write_fault, &writable, NULL);
+
+ if (exit_on_memory_fault && pfn == KVM_PFN_ERR_FAULT) {
+ memory_fault_flags = 0;
+ if (write_fault)
+ memory_fault_flags |= KVM_MEMORY_FAULT_FLAG_EXEC;
+ if (exec_fault)
+ memory_fault_flags |= KVM_MEMORY_FAULT_FLAG_EXEC;
+ kvm_populate_efault_info(vcpu,
+ round_down(gfn * PAGE_SIZE, vma_pagesize), vma_pagesize,
+ memory_fault_flags);
+ return -EFAULT;
+ }
if (pfn == KVM_PFN_ERR_HWPOISON) {
kvm_send_hwpoison_signal(hva, vma_shift);
return 0;
--
2.41.0.rc0.172.g3f132b7071-goog
