On Tue, Nov 21, 2017 at 10:22 PM, Ingo Molnar <[email protected]> wrote: > > * Andy Lutomirski <[email protected]> wrote: > >> This sets up stack switching, including for SYSCALL. I think it's >> in decent shape. >> >> Known issues: >> - I think we're going to want a way to turn the stack switching on and >> off either at boot time or at runtime. It should be fairly >> straightforward >> to make it work. >> >> - I think the ORC unwinder isn't so good at dealing with stack overflows. >> It bails too early (I think), resulting in lots of ? entries. This >> isn't a regression with this series -- it's just something that could >> be improved. >> >> Ingo, patch 1 may be tip/urgent material. It fixes what I think is >> a bug in Xen. I'm having a hard time testing because it's being >> masked by a bigger unrelated bug that's keeping Xen from booting >> when configured to hit the bug I'm fixing. (The latter bug goes at >> least back to v4.13, I think I know roughtly what's wrong, and I've >> reported it to the maintainers.) > > Hm, with this series the previous IRQ vector bug appears again: > > [ 51.156370] do_IRQ: 16.34 No irq handler for vector > [ 57.511030] do_IRQ: 16.34 No irq handler for vector > [ 57.528335] do_IRQ: 16.34 No irq handler for vector > [ 57.533256] do_IRQ: 16.34 No irq handler for vector > [ 63.991913] do_IRQ: 16.34 No irq handler for vector > [ 63.996810] do_IRQ: 16.34 No irq handler for vector > > I've attached the reproducer config. Note that the system appears to be > working to > a certain extent (I could ssh to it and extract its config), but produces > these > warnings sporadically.
I'll try to reproduce this, but this is weird. This is vector 34, which is, or could be, a genuine IRQ vector. The only way I can think of that my series would have caused this is if I very severely broke common_interrupt, but I don't see how that could have happened without breaking everything. It's also weird that you're seeing this only on CPU 16. Maybe it's worth adding a WARN_ON to that warning to get a stack trace just in case. Thomas, any insight here? > but don't get the IRQ vector warnings. Ingo, are you saying that you only get the IRQ vector warnings with the SYSCALL hwframe fix applied? That's bizarre. Anyway, I booted your config (more or less -- I munged it through virtme-configkernel --update first) with 17 vCPUs and it seems fine. Is the issue reliable enough to bisect?
