On Thu, Oct 19, 2017 at 01:29:40PM +0200, Michał Koc wrote:
> ------ Wiadomość oryginalna ------
> *Temat: *Re: Openbsd 6.1 and Current Console Freezes and lockup Proxmox
> PVE5.0
> *Nadawca: *Mike Larkin <mlar...@azathoth.net>
> *Adresat: *Michał Koc <m...@prime.pl>
> *Kopia: *misc@openbsd.org
> *Data: *19.10.2017 08:36
> > On Fri, Oct 13, 2017 at 11:05:12PM +0200, Michał Koc wrote:
> > > > On Thu, Oct 12, 2017 at 03:11:31PM -0700, Mike Larkin wrote:
> > > > > On Thu, Oct 12, 2017 at 10:36:42PM +0200, Michał Koc wrote:
> > > > > > > On Thu, Oct 12, 2017 at 01:23:36PM +0200, Michał Koc wrote:
> > > > > > > > On Sun, Oct 08, 2017 at 11:59:52PM +0200, Oliver Marugg wrote:
> > > > > > > > > > On 7 Oct 2017, at 22:01, Mike Larkin wrote:
> > > > > > > > > > 
> > > > > > > > > > > On Sat, Oct 07, 2017 at 02:19:58PM +0200, Oliver Marugg 
> > > > > > > > > > > wrote:
> > > > > > > > > > > > Just to add a 4th situation of hangs: Login via proxmox 
> > > > > > > > > > > > (pve)/kvm
> > > > > > > > > > > > serial
> > > > > > > > > > > > console (via noVNC), login successful: Vm guest in pve 
> > > > > > > > > > > > hangs, cpu
> > > > > > > > > > > > usage at
> > > > > > > > > > > > above 102%. Only way is to hard stop the Vm guest. 
> > > > > > > > > > > > -oliver
> > > > > > > > > > > > 
> > > > > > > > > > > sounds like a kvm bug. Ask your provider to investigate 
> > > > > > > > > > > the host side
> > > > > > > > > > > when this
> > > > > > > > > > > happens.
> > > > > > > > > > Thanks Mike, will do so. The proxmox guys have also the 
> > > > > > > > > > idea that it could
> > > > > > > > > > be a bug in kvm hypervisor (which is the hypervisor part 
> > > > > > > > > > for proxmox) and
> > > > > > > > > > will affect OpenBSD since 4.9, they wrote me in their 
> > > > > > > > > > public forum. As far
> > > > > > > > > > as I understood they do not know what OpenBSD needs in kvm 
> > > > > > > > > > or what/where
> > > > > > > > > > should be fixed in kvm run OpenBSD without that freezes.
> > > > > > > > > > 
> > > > > > > > > > -oliver
> > > > > > > > > >From what I read, the cpu spins to 100%, which means 
> > > > > > > > > >somewhere on the host it's
> > > > > > > > > likely spinning also. Start with 
> > > > > > > > > systrace/ptrace/ktrace/whatever on the host
> > > > > > > > > qemu-kvm and go from there...
> > > > > > > > > 
> > > > > > > > > -ml
> > > > > > > > > 
> > > > > > > > > 
> > > > > > > > > 
> > > > > > > > Hi,
> > > > > > > > 
> > > > > > > > it looks like the cpu process of kvm (CPU 0/KVM) is issuing 
> > > > > > > > 1500+ of
> > > > > > > > ioctl(15, KVM_RUN, 0)  per second while running OpenBSD 6.2 
> > > > > > > > guest.
> > > > > > > > 
> > > > > > > What CPU profile is being presented to the OpenBSD guest?
> > > > > > > 
> > > > > > > I've seen things like this happen when a vCPU is claimed to have 
> > > > > > > monitor/mwait
> > > > > > > support, but the hypervisor implements those as NOPs, which just 
> > > > > > > results in
> > > > > > > spinning like this.
> > > > > > > 
> > > > > > > In short - try changing the type of CPU presented to the guest 
> > > > > > > and see if that
> > > > > > > changes behaviour. At least then you'll have more data points to 
> > > > > > > work with.
> > > > > > > 
> > > > > > > -ml
> > > > > > Okey,
> > > > > > How would You disable monitor/mwait support in KVM to be presented 
> > > > > > to guest
> > > > > > ?
> > > > > > 
> > > > > Well, monitor/mwait was just what I recall contributing to something 
> > > > > *like*
> > > > > this.
> > > > > 
> > > > PS, IIRC qemu -cpu ? will show you a list of recognized cpuid flags, 
> > > > from
> > > > which you can subtract off things you don't want.
> > > Hi Mike,
> > > 
> > > Guest OpenBSD has those flags presented:
> > > cpu0: FPU,VME,DE,PSE,TSC,MSR,MCE,CX8,APIC,MMX,HV,PERF
> > > 
> > > What else should I switch off to get desired effect ?
> > > 
> > Those flags are completely bizarre. Compare to vmm(4):
> > 
> > cpu0: 
> > FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,SEP,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,MMX,FXSR,SSE,SSE2,SSE3,PCLMUL,SSSE3,CX16,SSE4.1,SSE4.2,POPCNT,AES,XSAVE,AVX,F16C,RDRAND,HV,NXE,RDTSCP,LONG,LAHF,ITSC,FSGSBASE,SMEP,ERMS
> > 
> > >From what you said above, proxmox doesn't even expose PAE or PGE, which 
> > >means
> > it's emulating something like a 1990s era 80486 CPU. It doesn't even claim 
> > to
> > support LONG, which means no 64 bit mode either.
> > 
> > It sounds like whatever hypervisor you are using is completely messed up. 
> > You
> > need to take this up with the proxmox or KVM people.
> > 
> > -ml
> > 
> > 
> Hi Mike,
> 
> after some fiddling around with various setting it looks like setting
> machine in <type arch='x86_64' machine='pc-q35-2.8'>hvm</type> to q35 solves
> the problem at least partially.
> 
> The host cpu consumption in below 2% and I cannot see any hangs. Even under
> heavy cpu load.
> 
> BR
> M.K.
> 
> 

That's good to know. Thanks.

-ml

Reply via email to