Hi Dongjiu Geng, On 06/01/18 16:02, Dongjiu Geng wrote: > The ARM64 RAS SError Interrupt(SEI) syndrome value is specific to the > guest and user space needs a way to tell KVM this value. So we add a > new ioctl. Before user space specifies the Exception Syndrome Register > ESR(ESR), it firstly checks that whether KVM has the capability to > set the guest ESR, If has, will set it. Otherwise, nothing to do. > > For this ESR specifying, Only support for AArch64, not support AArch32. After this patch user-space can trigger an SError in the guest. If it wants to migrate the guest, how does the pending SError get migrated? I think we need to fix migration first. Andrew Jones suggested using KVM_GET/SET_VCPU_EVENTS: https://www.spinics.net/lists/arm-kernel/msg616846.html Given KVM uses kvm_inject_vabt() on v8.0 hardware too, we should cover systems without the v8.2 RAS Extensions with the same API. I think this means a bit to read/write whether SError is pending, and another to indicate the ESR should be set/read. CPUs without the v8.2 RAS Extensions can reject pending-SError that had an ESR. user-space can then use the 'for migration' calls to make a 'new' SError pending. Now that the cpufeature bits are queued, I think this can be split up into two separate series for v4.16-rc1, one to tackle NOTIFY_SEI and the associated plumbing. The second for the KVM 'make SError pending' API. > diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c > index 5c7f657..738ae90 100644 > --- a/arch/arm64/kvm/guest.c > +++ b/arch/arm64/kvm/guest.c > @@ -277,6 +277,11 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, > return -EINVAL; > } > > +int kvm_arm_set_sei_esr(struct kvm_vcpu *vcpu, u32 *syndrome) > +{ > + return -EINVAL; > +} Does nothing in the patch that adds the support? This is a bit odd. (oh, its hiding in patch 6...) Thanks, James -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
