Re: bisected: 4.18-rc* regression: x86-32 troubles (with timers?)

From: Meelis Roos
Date: Tue Jul 24 2018 - 02:11:45 EST


> >> I would be curious as well about that whether revert would make it
> >> work. What's the value of sysctl net.core.bpf_jit_enable ? Does it
> >> change anything if you set it to 0 (only interpreter) or 1 (JIT
> >> enabled). Seems a bit strange to me that bisect ended at this commit
> >> given the issue you have. The JIT itself was also new in this window
> >> fwiw. In any case some more debug info would be great to have.
> >
> > net.core.bpf_jit_enable is 1.
> >
> > Since it breaks bootup, I can not easily change the value at runtime (it
> > would be postfactum). Do you mean changing the
> > CONFIG_BPF_JIT_ALWAYS_ON=y option?
>
> Yeah if you chance it to N, and don't have any fixed /etc/sysctl.conf
> setting, then you'll boot up with interpreter first (net.core.bpf_jit_enable
> as 0). Curious whether that works just fine for you.

Disabled CONFIG_BPF_JIT_ALWAYS_ON on v4.18-rc5 and it works, tested on 2
bootups.

--
Meelis Roos (mroos@xxxxxxxx)