From 0161ed77586b53f080f1fa4c3d95284dcd092b84 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Thu, 3 Sep 2015 15:47:47 +0100 Subject: [PATCH] Handle KVM_EXIT_SYSTEM_EVENT on any VCPU When VCPU #0 exits (e.g. due to KVM_EXIT_SYSTEM_EVENT), it sends SIGKVMEXIT to all other VCPUs, waits for them to exit, then tears down any remaining context. The signalling of SIGKVMEXIT is critical to forcing VCPUs to shut down in response to a system event (e.g. PSCI SYSTEM_OFF). VCPUs other that VCPU #0 simply exit in kvm_cpu_thread without forcing other CPUs to shut down. Thus if a system event is taken on a VCPU other than VCPU #0, the remaining CPUs are left online. This results in KVM tool not exiting as expected when a system event is taken on a VCPU other than VCPU #0 (as may happen if the guest panics). Fix this by tearing down all CPUs upon a system event, regardless of the CPU on which the event occurred. While this means the VCPU thread will signal itself, and VCPU #0 will signal all other VCPU threads a second time, these are harmless. Signed-off-by: Mark Rutland Cc: Marc Zyngier Cc: Suzuki Poulose Cc: Will Deacon Signed-off-by: Will Deacon --- kvm-cpu.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/kvm-cpu.c b/kvm-cpu.c index 5d90664..664795f 100644 --- a/kvm-cpu.c +++ b/kvm-cpu.c @@ -166,13 +166,18 @@ int kvm_cpu__start(struct kvm_cpu *cpu) * treat all system events as shutdown request. */ switch (cpu->kvm_run->system_event.type) { - case KVM_SYSTEM_EVENT_RESET: - /* Fall through for now */ - case KVM_SYSTEM_EVENT_SHUTDOWN: - goto exit_kvm; default: pr_warning("unknown system event type %d", cpu->kvm_run->system_event.type); + /* fall through for now */ + case KVM_SYSTEM_EVENT_RESET: + /* Fall through for now */ + case KVM_SYSTEM_EVENT_SHUTDOWN: + /* + * Ensure that all VCPUs are torn down, + * regardless of which CPU generated the event. + */ + kvm_cpu__reboot(cpu->kvm); goto exit_kvm; }; break;