On Thu, Oct 13, 2022 at 03:03:14PM +1000, Nicholas Piggin wrote: > On Thu Oct 13, 2022 at 10:21 AM AEST, Guenter Roeck wrote: > > On Thu, Oct 13, 2022 at 11:03:34AM +1100, Michael Ellerman wrote: > > > Guenter Roeck <li...@roeck-us.net> writes: > > > > On Wed, Oct 12, 2022 at 11:20:38AM -0600, Jason A. Donenfeld wrote: > > > >> > > > >> I've also managed to not hit this bug a few times. When it triggers, > > > >> after "kprobes: kprobe jump-optimization is enabled. All kprobes are > > > >> optimized if possible.", there's a long hang - tens seconds before it > > > >> continues. When it doesn't trigger, there's no hang at that point in > > > >> the > > > >> boot process. > > > >> > > > > > > > > I managed to bisect the problem. See below for results. Reverting the > > > > offending patch fixes the problem for me. > > > > > > Thanks. > > > > > > This is probably down to me/us not testing with PREEMPT enabled enough. > > > > > Not sure. My configuration has > > > > CONFIG_PREEMPT_NONE=y > > # CONFIG_PREEMPT_VOLUNTARY is not set > > # CONFIG_PREEMPT is not set > > Thanks very much for helping with this. The config snippet you posted here > https://lists.ozlabs.org/pipermail/linuxppc-dev/2022-October/249758.html > has CONFIG_PREEMPT=y. How do you turn that into a .config, olddefconfig? > > I can't reproduce this so far using your config and qemu command line, > but the patch you've bisected it to definitely could cause this. I'll > keep trying...
Voila https://xn--4db.cc/dt00j0mt this repros it for me. > > Thanks, > Nick > > [...] > > > > # first bad commit: [e485f6c751e0a969327336c635ca602feea117f0] > > > > powerpc/64/interrupt: Fix return to masked context after hard-mask irq > > > > becomes pending >
