[PATCH v9 5/7] arm64: kvm: Introduce KVM_ARM_SET_SERROR_ESR ioctl
From: james.morse@arm.com (James Morse)
Date: 2018-01-23 19:08:59
Also in:
kvmarm, linux-acpi, lkml
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.
quoted hunk ↗ jump to hunk
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