From: Sean Christopherson <seanjc@xxxxxxxxxx>
[ Upstream commit a61d7c5432ac5a953bbcec17af031661c2bd201d ]
Trace exceptions that are re-injected, not just those that KVM is
injecting for the first time. Debugging re-injection bugs is painful
enough as is, not having visibility into what KVM is doing only makes
things worse.
Delay propagating pending=>injected in the non-reinjection path so that
the tracing can properly identify reinjected exceptions.
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Reviewed-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@xxxxxxxxxx>
Message-Id: <25470690a38b4d2b32b6204875dd35676c65c9f2.1651440202.git.maciej.szmigiero@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Stable-dep-of: 5623f751bd9c ("KVM: x86: Treat #DBs from the emulator as fault-like (code and DR7.GD=1)")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/x86/kvm/trace.h | 12 ++++++++----
arch/x86/kvm/x86.c | 16 +++++++++-------
2 files changed, 17 insertions(+), 11 deletions(-)
diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index a2835d784f4b..3d4988ea8b57 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -304,25 +304,29 @@ TRACE_EVENT(kvm_inj_virq,
* Tracepoint for kvm interrupt injection:
*/
TRACE_EVENT(kvm_inj_exception,
- TP_PROTO(unsigned exception, bool has_error, unsigned error_code),
- TP_ARGS(exception, has_error, error_code),
+ TP_PROTO(unsigned exception, bool has_error, unsigned error_code,
+ bool reinjected),
+ TP_ARGS(exception, has_error, error_code, reinjected),
TP_STRUCT__entry(
__field( u8, exception )
__field( u8, has_error )
__field( u32, error_code )
+ __field( bool, reinjected )
),
TP_fast_assign(
__entry->exception = exception;
__entry->has_error = has_error;
__entry->error_code = error_code;
+ __entry->reinjected = reinjected;
),
- TP_printk("%s (0x%x)",
+ TP_printk("%s (0x%x)%s",
__print_symbolic(__entry->exception, kvm_trace_sym_exc),
/* FIXME: don't print error_code if not present */
- __entry->has_error ? __entry->error_code : 0)
+ __entry->has_error ? __entry->error_code : 0,
+ __entry->reinjected ? " [reinjected]" : "")
);
/*
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f3473418dcd5..17bb3d0e2d13 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8347,6 +8347,11 @@ static void update_cr8_intercept(struct kvm_vcpu *vcpu)
static void kvm_inject_exception(struct kvm_vcpu *vcpu)
{
+ trace_kvm_inj_exception(vcpu->arch.exception.nr,
+ vcpu->arch.exception.has_error_code,
+ vcpu->arch.exception.error_code,
+ vcpu->arch.exception.injected);
+
if (vcpu->arch.exception.error_code && !is_protmode(vcpu))
vcpu->arch.exception.error_code = false;
kvm_x86_ops.queue_exception(vcpu);
@@ -8404,13 +8409,6 @@ static void inject_pending_event(struct kvm_vcpu *vcpu, bool *req_immediate_exit
/* try to inject new event if pending */
if (vcpu->arch.exception.pending) {
- trace_kvm_inj_exception(vcpu->arch.exception.nr,
- vcpu->arch.exception.has_error_code,
- vcpu->arch.exception.error_code);
-
- vcpu->arch.exception.pending = false;
- vcpu->arch.exception.injected = true;
-
if (exception_type(vcpu->arch.exception.nr) == EXCPT_FAULT)
__kvm_set_rflags(vcpu, kvm_get_rflags(vcpu) |
X86_EFLAGS_RF);
@@ -8424,6 +8422,10 @@ static void inject_pending_event(struct kvm_vcpu *vcpu, bool *req_immediate_exit
}
kvm_inject_exception(vcpu);
+
+ vcpu->arch.exception.pending = false;
+ vcpu->arch.exception.injected = true;
+
can_inject = false;
}
--
2.35.1
