On 12/12/2023 12:47 PM, Shashar, Sagi wrote: > > > -----Original Message----- > From: Sagi Shahar <[email protected]> > Sent: Tuesday, December 12, 2023 12:47 PM > To: [email protected]; Ackerley Tng <[email protected]>; > Afranji, Ryan <[email protected]>; Aktas, Erdem <[email protected]>; > Sagi Shahar <[email protected]>; Yamahata, Isaku <[email protected]> > Cc: Sean Christopherson <[email protected]>; Paolo Bonzini > <[email protected]>; Shuah Khan <[email protected]>; Peter Gonda > <[email protected]>; Xu, Haibo1 <[email protected]>; Chao Peng > <[email protected]>; Annapurve, Vishal <[email protected]>; > Roger Wang <[email protected]>; Vipin Sharma <[email protected]>; > [email protected]; [email protected]; [email protected]; > [email protected]; [email protected] > Subject: [RFC PATCH v5 27/29] KVM: selftests: Propagate KVM_EXIT_MEMORY_FAULT > to userspace > > Allow userspace to handle KVM_EXIT_MEMORY_FAULT instead of triggering > TEST_ASSERT. > > From the KVM_EXIT_MEMORY_FAULT documentation: > Note! KVM_EXIT_MEMORY_FAULT is unique among all KVM exit reasons in that it > accompanies a return code of '-1', not '0'! errno will always be set to > EFAULT or EHWPOISON when KVM exits with KVM_EXIT_MEMORY_FAULT, userspace > should assume kvm_run.exit_reason is stale/undefined for all other error > numbers. If KVM exits to userspace with KVM_EXIT_MEMORY_FAULT, most likely it's because the guest attempts to access the gfn in a way that is different from what the KVM is configured, in terms of private/shared property. I'd suggest to drop this patch and work on the selftests code to eliminate this exit. If we need a testcase to catch this exit intentionally, we may call _vcpu_run() directly from the testcase and keep the common API vcpu_run() intact. > > Signed-off-by: Sagi Shahar <[email protected]> > --- > tools/testing/selftests/kvm/lib/kvm_util.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c > b/tools/testing/selftests/kvm/lib/kvm_util.c > index d024abc5379c..8fb041e51484 100644 > --- a/tools/testing/selftests/kvm/lib/kvm_util.c > +++ b/tools/testing/selftests/kvm/lib/kvm_util.c > @@ -1742,6 +1742,10 @@ void vcpu_run(struct kvm_vcpu *vcpu) { > int ret = _vcpu_run(vcpu); > > + // Allow this scenario to be handled by the caller. > + if (ret == -1 && errno == EFAULT) > + return; > + > TEST_ASSERT(!ret, KVM_IOCTL_ERROR(KVM_RUN, ret)); } > > -- > 2.43.0.472.g3155946c3a-goog >
