On Thu, Sep 22, 2022 at 11:20:39AM -0700,
isaku.yamahata@xxxxxxxxx wrote:
> From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
>
> and pass kvm_usage_count with kvm_lock. Move kvm_arch_post_init_vm() under
> kvm_arch_add_vm(). Replace enable/disable_hardware_all() with the default
> implementation of kvm_arch_add/del_vm(). Later kvm_arch_post_init_vm() is
> deleted once x86 overrides kvm_arch_add_vm().
>
> Suggested-by: Sean Christopherson <seanjc@xxxxxxxxxx>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
> ---
> include/linux/kvm_host.h | 2 +
> virt/kvm/kvm_main.c | 121 ++++++++++++++++++++-------------------
> 2 files changed, 65 insertions(+), 58 deletions(-)
>
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index eab352902de7..3fbb01bbac98 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -1445,6 +1445,8 @@ int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu);
> bool kvm_arch_dy_runnable(struct kvm_vcpu *vcpu);
> bool kvm_arch_dy_has_pending_interrupt(struct kvm_vcpu *vcpu);
> int kvm_arch_post_init_vm(struct kvm *kvm);
> +int kvm_arch_add_vm(struct kvm *kvm, int usage_count);
> +int kvm_arch_del_vm(int usage_count);
> void kvm_arch_pre_destroy_vm(struct kvm *kvm);
> int kvm_arch_create_vm_debugfs(struct kvm *kvm);
>
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index c4b908553726..e2c8823786ff 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -142,8 +142,9 @@ static int kvm_no_compat_open(struct inode *inode, struct file *file)
> #define KVM_COMPAT(c) .compat_ioctl = kvm_no_compat_ioctl, \
> .open = kvm_no_compat_open
> #endif
> -static int hardware_enable_all(void);
> -static void hardware_disable_all(void);
> +static void hardware_enable_nolock(void *junk);
> +static void hardware_disable_nolock(void *junk);
> +static void kvm_del_vm(void);
>
> static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
>
> @@ -1106,6 +1107,41 @@ int __weak kvm_arch_post_init_vm(struct kvm *kvm)
> return 0;
> }
>
> +/*
> + * Called after the VM is otherwise initialized, but just before adding it to
> + * the vm_list.
> + */
> +int __weak kvm_arch_add_vm(struct kvm *kvm, int usage_count)
> +{
> + int r = 0;
> +
> + if (usage_count != 1)
> + return 0;
Oops. This line should be.
+ return kvm_arch_post_init_vm(kvm);
"KVM: x86: Duplicate arch callbacks related to pm events and compat check"
should have same line. "KVM: Eliminate kvm_arch_post_init_vm()" should include
kvm_mmu_post_init_vm().
It creates a kernel thread. kvm unit test didn't catch it.
Thanks,
> +
> + atomic_set(&hardware_enable_failed, 0);
> + on_each_cpu(hardware_enable_nolock, NULL, 1);
> +
> + if (atomic_read(&hardware_enable_failed)) {
> + r = -EBUSY;
> + goto err;
> + }
> +
> + r = kvm_arch_post_init_vm(kvm);
> +err:
> + if (r)
> + on_each_cpu(hardware_disable_nolock, NULL, 1);
> + return r;
> +}
> +
> +int __weak kvm_arch_del_vm(int usage_count)
> +{
> + if (usage_count)
> + return 0;
> +
> + on_each_cpu(hardware_disable_nolock, NULL, 1);
> + return 0;
> +}
> +
> /*
> * Called just after removing the VM from the vm_list, but before doing any
> * other destruction.
--
Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
