The code looks correct, but I think it would be nicer to change
hrtimer_nanosleep to take a kernel pointer and have all three
callers (common_nsleep, sys_nanosleep and compat_sys_nanosleep)
do the copy_to_user/put_compat_timespec in the caller.
This would also make it possible to get rid of set_fs() in
compat_sys_clock_nanosleep().
Arnd <><
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