sys_gettimeofday racy or not?

[Wichert Akkerman]

This just happened to catch my eye and it's probably perfectly
valid, but if so please educate me on why it is. In kernel/time.c
sys_gettimeofday() there is this code:

        if (unlikely(tz != NULL)) {
                if (copy_to_user(tz, &sys_tz, sizeof(sys_tz)))
                        return -EFAULT;
        }

what prevents sys_tz from being changed while this code runs?

Wichert.

-- 
Wichert Akkerman <wichert@xxxxxxxxx>    It is simple to make things.
http://www.wiggy.net/                   It is hard to make things simple.
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