On Wed, Mar 22, 2017 at 2:25 PM, David Woodhouse <dwmw2@xxxxxxxxxxxxx> wrote: > From: David Woodhouse <dwmw@xxxxxxxxxxxx> > > Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx> > --- > drivers/pci/proc.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c > index 2d9cfa4..a940f4b 100644 > --- a/drivers/pci/proc.c > +++ b/drivers/pci/proc.c > @@ -17,6 +17,11 @@ > > static int proc_initialized; /* = 0 */ > > +#ifdef __aarch64__ > +/* ARM64 wants to be special and not expose this through /proc like everyone else */ > +#undef HAVE_PCI_MMAP > +#endif I'd still prefer this to be a whitelist of the existing architectures using PCI MMAP in procfs, there is really no reason for arm64 to be special, the one thing we want to control here is whether new architectures (including arm64) that have never had either the sysfs or the procfs interface should get one or both of them. As it seems that there are important use cases for the sysfs interface and your patch series will just make that work everywhere, I'd argue that we should just always provide the sysfs interface now, and use HAVE_PCI_MMAP only control the procfs interface. That way, we turn on the sysfs interface on arc, arm64, frv and tile as well as any future architecture with PCI support, but leave the procfs support as opt-in. Arnd