To allow arm64 syscalls to accept tagged pointers from userspace, we must untag them when they are passed to the kernel. Since untagging is done in generic parts of the kernel, the untagged_addr macro needs to be defined for all architectures.
Define it as a noop for architectures other than arm64.
Acked-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Andrey Konovalov andreyknvl@google.com --- include/linux/mm.h | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/include/linux/mm.h b/include/linux/mm.h index 6b10c21630f5..44041df804a6 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 + #ifndef __pa_symbol #define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0)) #endif