Re: [4.14] Failing selftest timer/adjtick

Greg KH
2021-02-11T10:48:09Z

On Thu, Feb 11, 2021 at 11:33:05AM +0100, Joerg Vehlow wrote:
> Hi Miroslav,
>
> On 2/10/2021 2:19 PM, Miroslav Lichvar wrote:
> > That patch cannot be applied alone. It would break the timekeeping in
> > not so obvious ways as there will be unexpected sources of the NTP
> > tracking error. IIRC, at least the following changes would need to be
> > included with it. There may be others.
> >
> > c2cda2a5bda9 ("timekeeping/ntp: Don't align NTP frequency adjustments to ticks")
> > aea3706cfc4d ("timekeeping: Remove CONFIG_GENERIC_TIME_VSYSCALL_OLD")
> > d4d1fc61eb38 ("ia64: Update fsyscall gettime to use modern vsyscall_update")
> >
> > My suggestion for a fix would be to increase the limit in the failing
> > test.
> Thanks, that's what I expected. But I still wonder why the test is failing
> almost 100% of time for me on qemu-arm64 (running on x86). Is this a
> regression in 4.14, that was working at some point or was it never tested on
> arm?

Does it work on a real system? That's the proper test...