On 2025-01-22 08:23:35-0800, Richard Cochran wrote:
> On Wed, Jan 22, 2025 at 08:30:51AM +0100, Arnd Bergmann wrote:
> > On Tue, Jan 21, 2025, at 23:41, Thomas Weißschuh wrote:
> > > Pointer arguments passed to ioctls need to pass through compat_ptr() to
> > > work correctly on s390; as explained in Documentation/driver-api/ioctl.rst.
> > > Plumb the compat_ioctl callback through 'struct posix_clock_operations'
> > > and handle the different ioctls cmds in the new ptp_compat_ioctl().
> > >
> > > Using compat_ptr_ioctl is not possible.
> > > For the commands PTP_ENABLE_PPS/PTP_ENABLE_PPS2 on s390
> > > it would corrupt the argument 0x80000000, aka BIT(31) to zero.
> > >
> > > Fixes: 0606f422b453 ("posix clocks: Introduce dynamic clocks")
> > > Fixes: d94ba80ebbea ("ptp: Added a brand new class driver for ptp clocks.")
> > > Cc: stable@xxxxxxxxxxxxxxx
> > > Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
> >
> > This looks correct to me,
>
> I'm not familiar with s390, but I can remember that the compat ioctl
> was nixed during review.
