diff options
| author | Oliver Upton <oliver.upton@linux.dev> | 2023-10-26 23:53:06 +0300 |
|---|---|---|
| committer | Oliver Upton <oliver.upton@linux.dev> | 2023-10-30 23:17:22 +0300 |
| commit | d11974dc5f208ae1c0fe62a9bcb47c0cdcd7b081 (patch) | |
| tree | 04c86b9135e06c5901f49947690115ba33ef215c | |
| parent | 06899aa5dd3d76e888b28d7e8d7304c0a7ec6262 (diff) | |
| download | linux-d11974dc5f208ae1c0fe62a9bcb47c0cdcd7b081.tar.xz | |
KVM: arm64: Add tracepoint for MMIO accesses where ISV==0
It is a pretty well known fact that KVM does not support MMIO emulation
without valid instruction syndrome information (ESR_EL2.ISV == 0). The
current kvm_pr_unimpl() is pretty useless, as it contains zero context
to relate the event to a vCPU.
Replace it with a precise tracepoint that dumps the relevant context
so the user can make sense of what the guest is doing.
Acked-by: Zenghui Yu <yuzenghui@huawei.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231026205306.3045075-1-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| -rw-r--r-- | arch/arm64/kvm/mmio.c | 4 | ||||
| -rw-r--r-- | arch/arm64/kvm/trace_arm.h | 25 |
2 files changed, 28 insertions, 1 deletions
diff --git a/arch/arm64/kvm/mmio.c b/arch/arm64/kvm/mmio.c index 3dd38a151d2a..200c8019a82a 100644 --- a/arch/arm64/kvm/mmio.c +++ b/arch/arm64/kvm/mmio.c @@ -135,6 +135,9 @@ int io_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa) * volunteered to do so, and bail out otherwise. */ if (!kvm_vcpu_dabt_isvalid(vcpu)) { + trace_kvm_mmio_nisv(*vcpu_pc(vcpu), kvm_vcpu_get_esr(vcpu), + kvm_vcpu_get_hfar(vcpu), fault_ipa); + if (test_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER, &vcpu->kvm->arch.flags)) { run->exit_reason = KVM_EXIT_ARM_NISV; @@ -143,7 +146,6 @@ int io_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa) return 0; } - kvm_pr_unimpl("Data abort outside memslots with no valid syndrome info\n"); return -ENOSYS; } diff --git a/arch/arm64/kvm/trace_arm.h b/arch/arm64/kvm/trace_arm.h index 8ad53104934d..c18c1a95831e 100644 --- a/arch/arm64/kvm/trace_arm.h +++ b/arch/arm64/kvm/trace_arm.h @@ -136,6 +136,31 @@ TRACE_EVENT(kvm_mmio_emulate, __entry->vcpu_pc, __entry->instr, __entry->cpsr) ); +TRACE_EVENT(kvm_mmio_nisv, + TP_PROTO(unsigned long vcpu_pc, unsigned long esr, + unsigned long far, unsigned long ipa), + TP_ARGS(vcpu_pc, esr, far, ipa), + + TP_STRUCT__entry( + __field( unsigned long, vcpu_pc ) + __field( unsigned long, esr ) + __field( unsigned long, far ) + __field( unsigned long, ipa ) + ), + + TP_fast_assign( + __entry->vcpu_pc = vcpu_pc; + __entry->esr = esr; + __entry->far = far; + __entry->ipa = ipa; + ), + + TP_printk("ipa %#016lx, esr %#016lx, far %#016lx, pc %#016lx", + __entry->ipa, __entry->esr, + __entry->far, __entry->vcpu_pc) +); + + TRACE_EVENT(kvm_set_way_flush, TP_PROTO(unsigned long vcpu_pc, bool cache), TP_ARGS(vcpu_pc, cache), |