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Subject: Re: Linux kernel: powerpc: KVM guest can trigger host crash on Power8
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To: Michael Ellerman <mpe@ellerman.id.au>
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From: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
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Hi Michael!

On 1/6/22 11:58, Michael Ellerman wrote:
>> 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.
> 
> Have you been able to try the different -smp options I suggested?
> 
> Can you separately test with (on the host):
> 
>  # echo 0 > /sys/module/kvm_hv/parameters/dynamic_mt_modes

I'm trying to turn off "dynamic_mt_modes" first and see if that makes any difference.

I will report back.

Adrian

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