On Fri, Sep 8, 2023 at 3:30 PM Anish Moorthy <amoorthy@xxxxxxxxxx> wrote:
>
> Implement KVM_CAP_MEMORY_FAULT_INFO for guest access failure in
> user_mem_abort().
>
> Signed-off-by: Anish Moorthy <amoorthy@xxxxxxxxxx>
> ---
> arch/arm64/kvm/mmu.c | 13 ++++++++++++-
> 1 file changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
> index 587a104f66c3..8ede6c5edc5f 100644
> --- a/arch/arm64/kvm/mmu.c
> +++ b/arch/arm64/kvm/mmu.c
> @@ -1408,6 +1408,7 @@ 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;
> + uint64_t memory_fault_flags;
>
> fault_granule = 1UL << ARM64_HW_PGTABLE_LEVEL_SHIFT(fault_level);
> write_fault = kvm_is_write_fault(vcpu);
> @@ -1507,8 +1508,18 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
> kvm_send_hwpoison_signal(hva, vma_shift);
> return 0;
> }
> - if (is_error_noslot_pfn(pfn))
> + if (is_error_noslot_pfn(pfn)) {
> + memory_fault_flags = 0;
> + if (write_fault)
> + memory_fault_flags = KVM_MEMORY_FAULT_FLAG_EXEC;
> + else if (exec_fault)
> + memory_fault_flags = KVM_MEMORY_FAULT_FLAG_EXEC;
> + else
> + memory_fault_flags = KVM_MEMORY_FAULT_FLAG_READ;
> + kvm_handle_guest_uaccess_fault(vcpu, round_down(gfn * PAGE_SIZE, vma_pagesize),
I think gfn * PAGE_SIZE is already rounded down to vma_pagesize. See
earlier in this function:
1484 vma_pagesize = 1UL << vma_shift;
1485 if (vma_pagesize == PMD_SIZE || vma_pagesize == PUD_SIZE)
1486 fault_ipa &= ~(vma_pagesize - 1);
1487
1488 gfn = fault_ipa >> PAGE_SHIFT;
> + vma_pagesize, memory_fault_flags);
> return -EFAULT;
> + }
>
> if (kvm_is_device_pfn(pfn)) {
> /*
> --
> 2.42.0.283.g2d96d420d3-goog
>
