From 667a83bf6a30b5660d02712dce9fb07e99abde38 Mon Sep 17 00:00:00 2001 From: Isaku Yamahata <isaku.yamahata@intel.com> Date: Wed, 30 Nov 2022 23:09:29 +0000 Subject: [PATCH] KVM: Remove on_each_cpu(hardware_disable_nolock) in kvm_exit() Drop the superfluous invocation of hardware_disable_nolock() during kvm_exit(), as it's nothing more than a glorified nop. KVM automatically disables hardware on all CPUs when the last VM is destroyed, and kvm_exit() cannot be called until the last VM goes away as the calling module is pinned by an elevated refcount of the fops associated with /dev/kvm. This holds true even on x86, where the caller of kvm_exit() is not kvm.ko, but is instead a dependent module, kvm_amd.ko or kvm_intel.ko, as kvm_chardev_ops.owner is set to the module that calls kvm_init(), not hardcoded to the base kvm.ko module. Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> [sean: rework changelog] Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20221130230934.1014142-46-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> --- virt/kvm/kvm_main.c | 1 - 1 file changed, 1 deletion(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index f6caee790dc82..d1ed34856412f 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -6050,7 +6050,6 @@ void kvm_exit(void) unregister_syscore_ops(&kvm_syscore_ops); unregister_reboot_notifier(&kvm_reboot_notifier); cpuhp_remove_state_nocalls(CPUHP_AP_KVM_ONLINE); - on_each_cpu(hardware_disable_nolock, NULL, 1); kvm_irqfd_exit(); free_cpumask_var(cpus_hardware_enabled); } -- GitLab