On Mon, Nov 13, 2017 at 1:03 PM, Thomas Gleixner tglx@linutronix.de 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