Messages in this thread | | | Date | Fri, 30 Oct 2020 16:43:37 +0100 | From | Lukasz Majewski <> | Subject | Re: [Y2038][time namespaces] Question regarding CLOCK_REALTIME support plans in Linux time namespaces |
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Hi Thomas,
> Lukasz, > > On Fri, Oct 30 2020 at 11:02, Lukasz Majewski wrote: > > I do have a question regarding the Linux time namespaces in respect > > of adding support for virtualizing the CLOCK_REALTIME. > > > > According to patch description [1] and time_namespaces documentation > > [2] the CLOCK_REALTIME is not supported (for now?) to avoid > > complexity and overhead in the kernel. > > > > Is there any plan to add support for it in a near future? > > Not really. Just having an offset on clock realtime would be incorrect > in a number of ways. Doing it correct is a massive trainwreck. > > For a debug aid, which is what you are looking for, the correctness > would not really matter, but providing that is a really slippery > slope. > > If at all we could hide it under a debug option which depends on > CONFIG_BROKEN and emitting a big fat warning in dmesg with a clear > statement that it _is_ broken, stays so forever and any attempt to > "fix" it results in a permanent ban from all kernel lists. > > Preferrably we don't go there.
I see. Thanks for the explanation.
Now, I do use QEMU to emulate ARM 32 bit system with recent kernel (5.1+). It works.
Another option would be to give a shoot to QEMU with the "user mode" to run cross-compiled tests (with using a cross-compiled glibc in earlier CI stage). The problem with above is the reliance on QEMU emulation of ARM syscalls (and if 64 bit time supporting syscalls - i.e. clock_settime64 - are available).
> > Thanks, > > tglx > >
Best regards,
Lukasz Majewski
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