Re: [PATCH v12 05/24] virt: geniezone: Add vm support

[Hillf Danton]

On Tue, 30 Jul 2024 16:24:17 +0800 Liju-clr Chen <liju-clr.chen@xxxxxxxxxxxx>
> +
> +static void gzvm_destroy_vm(struct gzvm *gzvm)
> +{
> +	pr_debug("VM-%u is going to be destroyed\n", gzvm->vm_id);
> +
> +	mutex_lock(&gzvm->lock);
> +
> +	gzvm_arch_destroy_vm(gzvm->vm_id);
> +
> +	mutex_lock(&gzvm_list_lock);
> +	list_del(&gzvm->vm_list);
> +	mutex_unlock(&gzvm_list_lock);
> +
> +	mutex_unlock(&gzvm->lock);
> +
> +	kfree(gzvm);
> +}
...
> +
> +void gzvm_destroy_all_vms(void)
> +{
> +	struct gzvm *gzvm, *tmp;
> +
> +	mutex_lock(&gzvm_list_lock);
> +	if (list_empty(&gzvm_list))
> +		goto out;
> +
> +	list_for_each_entry_safe(gzvm, tmp, &gzvm_list, vm_list)
> +		gzvm_destroy_vm(gzvm);
> +

You add a fking deadlock by invoking gzvm_destroy_vm() with gzvm_list_lock held.

> +out:
> +	mutex_unlock(&gzvm_list_lock);
> +}