On Mon, Nov 13, 2017 at 1:03 PM, Thomas Gleixner <[email protected]> wrote: > On Fri, 10 Nov 2017, Deepa Dinamani wrote: >> >> -#ifdef CONFIG_COMPAT >> - >> COMPAT_SYSCALL_DEFINE2(nanosleep, struct compat_timespec __user *, rqtp, >> struct compat_timespec __user *, rmtp) >> { >> @@ -1574,7 +1572,6 @@ COMPAT_SYSCALL_DEFINE2(nanosleep, struct >> compat_timespec __user *, rqtp, >> current->restart_block.nanosleep.compat_rmtp = rmtp; >> return hrtimer_nanosleep(&tu, HRTIMER_MODE_REL, CLOCK_MONOTONIC); >> } >> -#endif > > So if I'm not missing something important this will make the compat syscall > define available even for > > CONFIG_X86_64=y > CONFIG_IA32_EMULATION=n > CONFIG_X86_X32=n > > which is wrong because in that configuration we don't have any 32bit > executable support. So why would we need a compat syscall in that case?
I was thinking that we would switch the meaning of CONFIG_64BIT_TIME after all architectures have enabled support for 64 bit time_t syscalls. After that, I was going to use the config to mean enable only 64 bit time_t support and so all compat syscalls would have #ifndef CONFIG_64BIT_TIME around them. Compat syscalls do not mean compat anymore for these time syscalls as the data structure is defined in a way that they are the same on 64 bit and 32 bit architectures. But, you are right. It will leave in compat syscalls when it is not required now. I could add a dependency on CONFIG_COMPAT and __BITS_PER_LONG for now if you prefer. I could introduce additional dependencies later on. -Deepa
