On Wed, Jan 15, 2020 at 2:38 PM Pali Rohár <pali.rohar@xxxxxxxxx> wrote: > On Wednesday 15 January 2020 22:30:59 Namjae Jeon wrote: > > 2020-01-15 19:10 GMT+09:00, Arnd Bergmann <arnd@xxxxxxxx>: > > It is not described in the specification. I don't know exactly what > > the problem is because sys_tz.tz_minuteswest seems to work fine to me. > > It can be random garbage value ? > > > > > so if there is a choice, falling back to UTC would > > > be nicer. > > > > Okay. > > Arnd, what is the default value of sys_tz.tz_minuteswest? What is the > benefit of not using it? > > I though that timezone mount option is just an old hack when userspace > does not correctly set kernel's timezone and that this timezone mount > option should be in most cases avoided. The main problem is that it is system-wide and initialized at boot time through settimeofday() to a timezone picked by the system administrator. However, in user space, every user may set their own timezone with the 'TZ' variable, and the default timezone may be different inside of a container based on the contents of /etc/timezone in its root directory. > So also another question, what is benefit of having fs specific timezone > mount option? As it is fs specific it means that it would be used so > much. You can use it to access removable media that were written in a different timezone, or a partition that is shared with another OS running on the same machine but with different timezone settings. Arnd