From: Will Deacon <will@xxxxxxxxxx> To allow for re-injection of stage-2 faults on stage-1 page-table walks due to either a missing or read-only memslot, move the triage logic out of io_mem_abort() and into kvm_handle_guest_abort(), where these aborts can be handled before anything else. Signed-off-by: Will Deacon <will@xxxxxxxxxx> Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> Cc: Marc Zyngier <maz@xxxxxxxxxx> Cc: Quentin Perret <qperret@xxxxxxxxxx> Link: https://lore.kernel.org/r/20200729102821.23392-5-will@xxxxxxxxxx --- arch/arm64/kvm/mmio.c | 6 ------ arch/arm64/kvm/mmu.c | 13 ++++++++++++- 2 files changed, 12 insertions(+), 7 deletions(-) diff --git a/arch/arm64/kvm/mmio.c b/arch/arm64/kvm/mmio.c index 4e0366759726..58de2ae4f6bb 100644 --- a/arch/arm64/kvm/mmio.c +++ b/arch/arm64/kvm/mmio.c @@ -145,12 +145,6 @@ int io_mem_abort(struct kvm_vcpu *vcpu, struct kvm_run *run, return -ENOSYS; } - /* Page table accesses IO mem: tell guest to fix its TTBR */ - if (kvm_vcpu_dabt_iss1tw(vcpu)) { - kvm_inject_dabt(vcpu, kvm_vcpu_get_hfar(vcpu)); - return 1; - } - /* * Prepare MMIO operation. First decode the syndrome data we get * from the CPU. Then try if some in-kernel emulation feels diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 85b0ec9dd9ef..dc8464669efd 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -2105,12 +2105,23 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run) hva = gfn_to_hva_memslot_prot(memslot, gfn, &writable); write_fault = kvm_is_write_fault(vcpu); if (kvm_is_error_hva(hva) || (write_fault && !writable)) { + /* + * The guest has put either its instructions or its page-tables + * somewhere it shouldn't have. Userspace won't be able to do + * anything about this (there's no syndrome for a start), so + * re-inject the abort back into the guest. + */ if (is_iabt) { - /* Prefetch Abort on I/O address */ ret = -ENOEXEC; goto out; } + if (kvm_vcpu_dabt_iss1tw(vcpu)) { + kvm_inject_dabt(vcpu, kvm_vcpu_get_hfar(vcpu)); + ret = 1; + goto out_unlock; + } + /* * Check for a cache maintenance operation. Since we * ended-up here, we know it is outside of any memory -- 2.27.0
