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In-Reply-To: <20171124035102.28051-1-mpe@ellerman.id.au>
To: Michael Ellerman <mpe@ellerman.id.au>, linuxppc-dev@ozlabs.org
From: Michael Ellerman <patch-notifications@ellerman.id.au>
Cc: yilzhang@redhat.com, david@gibson.dropbear.id.au
Subject: Re: powerpc/kexec: Fix kexec/kdump in P9 guest kernels
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Date: Fri, 24 Nov 2017 20:46:41 +1100 (AEDT)
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On Fri, 2017-11-24 at 03:51:02 UTC, Michael Ellerman wrote:
> The code that cleans up the IAMR/AMOR before kexec'ing failed to
> remember that when we're running as a guest AMOR is not writable, it's
> hypervisor privileged.
> 
> They symptom is that the kexec stops before entering purgatory and
> nothing else is seen on the console. If you examine the state of the
> system all threads will be in the 0x700 program check handler.
> 
> Fix it by making the write to AMOR dependent on HV mode.
> 
> Fixes: 1e2a516e89fc ("powerpc/kexec: Fix radix to hash kexec due to IAMR/AMOR")
> Cc: stable@vger.kernel.org # v4.10+
> Reported-by: Yilin Zhang <yilzhang@redhat.com>
> Debugged-by: David Gibson <david@gibson.dropbear.id.au>
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
> Acked-by: Balbir Singh <bsingharora@gmail.com>
> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> Tested-by: David Gibson <david@gibson.dropbear.id.au>

Applied to powerpc fixes.

https://git.kernel.org/powerpc/c/2621e945fbf1d6df5f3f0ba7be5bae

cheers