Re: Linux kernel: powerpc: KVM guest can trigger host crash on Power8

Hi Michael!

Sorry for the long time without any responses. Shall we continue debugging this?

We're currently running 5.15.x on the host system and the guests and the testsuite
for gcc-9 still reproducibly kills the KVM host.

Adrian

On 11/1/21 07:53, Michael Ellerman wrote:

Sure, will give that a try.

I was able to crash my machine over the weekend, building openjdk, but I
haven't been able to reproduce it for ~24 hours now (I didn't change
anything).


Can you try running your guests with no SMT threads?

I think one of your guests was using:

  -smp 32,sockets=1,dies=1,cores=8,threads=4

Can you change that to:

  -smp 8,sockets=1,dies=1,cores=8,threads=1


And something similar for the other guest(s).

If the system is stable with those settings that would be useful
information, and would also mean you could use the system without it
crashing semi regularly.

cheers

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer - glaubitz@debian.org
`. `'   Freie Universitaet Berlin - glaubitz@physik.fu-berlin.de
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