Commit 20020f4c authored by Oliver Upton's avatar Oliver Upton Committed by Paolo Bonzini
Browse files

KVM: Get an fd before creating the VM 



Allocate a VM's fd at the very beginning of kvm_dev_ioctl_create_vm() so
that KVM can use the fd value to generate strigns, e.g. for debugfs,
when creating and initializing the VM.

Signed-off-by: default avatarOliver Upton <oupton@google.com>
Message-Id: <20220720092259.3491733-4-oliver.upton@linux.dev>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 58fc1166

virt/kvm/kvm_main.c

+17 −13
Original line number Diff line number Diff line
@@ -4889,25 +4889,27 @@ EXPORT_SYMBOL_GPL(file_is_kvm); 


static int kvm_dev_ioctl_create_vm(unsigned long type)

{

	int r;

	int r, fd;

	struct kvm *kvm;

	struct file *file;



	fd = get_unused_fd_flags(O_CLOEXEC);

	if (fd < 0)

		return fd;



	kvm = kvm_create_vm(type);

	if (IS_ERR(kvm))

		return PTR_ERR(kvm);

	if (IS_ERR(kvm)) {

		r = PTR_ERR(kvm);

		goto put_fd;

	}



#ifdef CONFIG_KVM_MMIO

	r = kvm_coalesced_mmio_init(kvm);

	if (r < 0)

		goto put_kvm;

#endif

	r = get_unused_fd_flags(O_CLOEXEC);

	if (r < 0)

		goto put_kvm;



	file = anon_inode_getfile("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);

	if (IS_ERR(file)) {

		put_unused_fd(r);

		r = PTR_ERR(file);

		goto put_kvm;

	}
@@ -4918,18 +4920,20 @@ static int kvm_dev_ioctl_create_vm(unsigned long type) 
	 * cases it will be called by the final fput(file) and will take

	 * care of doing kvm_put_kvm(kvm).

	 */

	if (kvm_create_vm_debugfs(kvm, r) < 0) {

		put_unused_fd(r);

	if (kvm_create_vm_debugfs(kvm, fd) < 0) {

		fput(file);

		return -ENOMEM;

		r = -ENOMEM;

		goto put_fd;

	}

	kvm_uevent_notify_change(KVM_EVENT_CREATE_VM, kvm);



	fd_install(r, file);

	return r;

	fd_install(fd, file);

	return fd;



put_kvm:

	kvm_put_kvm(kvm);

put_fd:

	put_unused_fd(fd);

	return r;

}