From ca242ac9960dc61530e25a2c190e4e13fd5f1ecb Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Tue, 21 Sep 2010 19:59:43 +0200 Subject: [PATCH] KVM: Fix reboot on Intel hosts When we reboot, we disable vmx extensions or otherwise INIT gets blocked. If a task on another cpu hits a vmx instruction, it will fault if vmx is disabled. We trap that to avoid a nasty oops and spin until the reboot completes. Problem is, we sleep with interrupts disabled. This blocks smp_send_stop() from running, and the reboot process halts. Fix by enabling interrupts before spinning. KVM-Stable-Tag. Signed-off-by: Avi Kivity Signed-off-by: Marcelo Tosatti --- virt/kvm/kvm_main.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index d4853a54771a..5186e728c53e 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1970,10 +1970,12 @@ static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val, asmlinkage void kvm_handle_fault_on_reboot(void) { - if (kvm_rebooting) + if (kvm_rebooting) { /* spin while reset goes on */ + local_irq_enable(); while (true) ; + } /* Fault while not rebooting. We want the trace. */ BUG(); } -- 2.20.1