[PATCH v10 1/3] arm64: Add __NR_* definitions for compat syscalls

Arnd Bergmann arnd at arndb.de
Wed Jan 28 13:35:01 PST 2015

On Wednesday 28 January 2015 15:31:49 Timur Tabi wrote:
> On Fri, Jul 4, 2014 at 2:28 AM, AKASHI Takahiro
> <takahiro.akashi at linaro.org> wrote:
> > +#define __ARM_NR_COMPAT_BASE           0x0f0000
> > +#define __ARM_NR_compat_cacheflush     (__ARM_NR_COMPAT_BASE+2)
> > +#define __ARM_NR_compat_set_tls                (__ARM_NR_COMPAT_BASE+5)
> I know this patch is six months old, but I was wondering if anyone
> knows of any plans to make these syscalls available to 64-bit apps?
> We have a 32-bit app that uses __ARM_NR_compat_cacheflush, and we'd
> like to port that app to 64-bit.  I'm just not sure how to start doing
> that, since there don't appear to be any 64-bit ARM-specific syscalls.

You can add architecture specific syscalls by using the 16 numbers following
__NR_arch_specific_syscall. Whether it makes sense to have a cacheflush
syscall on arm64, I have no idea.

I believe that we should not need a set_tls syscall though.


More information about the linux-arm-kernel mailing list