On Fri, Apr 22, 2022 at 02:29:41PM -0700, Axel Rasmussen wrote: [...] > --- a/include/uapi/linux/userfaultfd.h > +++ b/include/uapi/linux/userfaultfd.h > @@ -12,6 +12,10 @@ > > #include <linux/types.h> > > +/* ioctls for /dev/userfaultfd */ > +#define USERFAULTFD_IOC 0xAA > +#define USERFAULTFD_IOC_NEW _IOWR(USERFAULTFD_IOC, 0x00, int) Why this new ioctl is defined using _IOWR()? Since it neither reads from user memory nor writes into user memory, it should rather be defined using _IO(), shouldn't it? -- ldv
