Am 04.06.19 um 13:44 schrieb Andrey Konovalov: > Architectures that support memory tagging have a need to perform untagging > (stripping the tag) in various parts of the kernel. This patch adds an > untagged_addr() macro, which is defined as noop for architectures that do > not support memory tagging. The oncoming patch series will define it at > least for sparc64 and arm64. > > Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx> > Reviewed-by: Khalid Aziz <khalid.aziz@xxxxxxxxxx> > Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> > --- > include/linux/mm.h | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 0e8834ac32b7..949d43e9c0b6 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -99,6 +99,10 @@ extern int mmap_rnd_compat_bits __read_mostly; > #include <asm/pgtable.h> > #include <asm/processor.h> > > +#ifndef untagged_addr > +#define untagged_addr(addr) (addr) > +#endif > + Maybe add a comment what tagging actually is? Cause that is not really obvious from the context. Christian. > #ifndef __pa_symbol > #define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0)) > #endif