From 58d6b15e9da5042a99c9c30ad725792e4569150e Mon Sep 17 00:00:00 2001 From: James Morse Date: Mon, 22 Jan 2018 18:19:06 +0000 Subject: KVM: arm/arm64: Handle CPU_PM_ENTER_FAILED cpu_pm_enter() calls the pm notifier chain with CPU_PM_ENTER, then if there is a failure: CPU_PM_ENTER_FAILED. When KVM receives CPU_PM_ENTER it calls cpu_hyp_reset() which will return us to the hyp-stub. If we subsequently get a CPU_PM_ENTER_FAILED, KVM does nothing, leaving the CPU running with the hyp-stub, at odds with kvm_arm_hardware_enabled. Add CPU_PM_ENTER_FAILED as a fallthrough for CPU_PM_EXIT, this reloads KVM based on kvm_arm_hardware_enabled. This is safe even if CPU_PM_ENTER never gets as far as KVM, as cpu_hyp_reinit() calls cpu_hyp_reset() to make sure the hyp-stub is loaded before reloading KVM. Fixes: 67f691976662 ("arm64: kvm: allows kvm cpu hotplug") Cc: # v4.7+ CC: Lorenzo Pieralisi Reviewed-by: Christoffer Dall Signed-off-by: James Morse Signed-off-by: Christoffer Dall --- virt/kvm/arm/arm.c | 1 + 1 file changed, 1 insertion(+) diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c index 59d8e04c19fa..639dca0c0560 100644 --- a/virt/kvm/arm/arm.c +++ b/virt/kvm/arm/arm.c @@ -1262,6 +1262,7 @@ static int hyp_init_cpu_pm_notifier(struct notifier_block *self, cpu_hyp_reset(); return NOTIFY_OK; + case CPU_PM_ENTER_FAILED: case CPU_PM_EXIT: if (__this_cpu_read(kvm_arm_hardware_enabled)) /* The hardware was enabled before suspend. */ -- cgit