Hi Arnd, On Mon, 19 Nov 2018 at 21:22, Arnd Bergmann <arnd@xxxxxxxx> wrote: > > On Thu, Nov 15, 2018 at 7:14 AM Firoz Khan <firoz.khan@xxxxxxxxxx> wrote: > > > > The 2nd option will be the recommended one. For that, I > > added the __NR_syscalls macro in uapi/asm/unistd.h along > > with __NR_Linux_syscalls. The macro __NR_syscalls also > > added for making the name convention same across all > > architecture. While __NR_syscalls isn't strictly part of > > the uapi, having it as part of the generated header to > > simplifies the implementation. We also need to enclose > > this macro with #ifdef __KERNEL__ to avoid side effects. > > I fear this doesn't work the way you hoped: > > > --- a/arch/mips/include/uapi/asm/unistd.h > > +++ b/arch/mips/include/uapi/asm/unistd.h > > @@ -391,16 +391,19 @@ > > #define __NR_rseq (__NR_Linux + 367) > > #define __NR_io_pgetevents (__NR_Linux + 368) > > > > +#ifdef __KERNEL__ > > +#define __NR_syscalls 368 > > +#endif > > We now have three different definitions of __NR_syscalls, > one for each ABI. User space previously saw the correct > one (now it doesn't see any, but that's ok). > > > /* > > * Offset of the last Linux o32 flavoured syscall > > */ > > -#define __NR_Linux_syscalls 368 > > +#define __NR_Linux_syscalls __NR_syscalls > > so this part part again is ok. > > > #endif /* _MIPS_SIM == _MIPS_SIM_ABI32 */ > > > > #define __NR_O32_Linux 4000 > > -#define __NR_O32_Linux_syscalls 368 > > +#define __NR_O32_Linux_syscalls __NR_syscalls > > but this part is not: Now __NR_O32_Linux_syscalls is defined > to __NR_syscalls, which may be one of the three values. > Any usage of __NR_O32_Linux_syscalls in a 64-bit kernel > is then clearly wrong. > > > #endif /* _MIPS_SIM == _MIPS_SIM_NABI32 */ > > > > #define __NR_N32_Linux 6000 > > -#define __NR_N32_Linux_syscalls 332 > > +#define __NR_N32_Linux_syscalls __NR_syscalls > > Same for this one. Thanks for the feedback. Will address all the comments. Firoz > > Arnd
