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 for <linuxppc-dev@ozlabs.org> from <stewart@linux.vnet.ibm.com>;
 Thu, 4 Aug 2016 00:14:48 -0400
From: Stewart Smith <stewart@linux.vnet.ibm.com>
To: Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com>,
 linuxppc-dev <linuxppc-dev@ozlabs.org>,
 Benjamin Herrenschmidt <benh@kernel.crashing.org>,
 Paul Mackerras <paulus@samba.org>, Michael Ellerman <mpe@ellerman.id.au>
Cc: "Shreyas B. Prabhu" <shreyas@linux.vnet.ibm.com>
Subject: Re: [PATCH v2 3/3] powernv: Fix MCE handler to avoid trashing CR0/CR1
 registers.
In-Reply-To: <20160301054817.15714.20605.stgit@mars.in.ibm.com>
References: <20160301054655.15714.48085.stgit@mars.in.ibm.com>
 <20160301054817.15714.20605.stgit@mars.in.ibm.com>
Date: Thu, 04 Aug 2016 14:14:39 +1000
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Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com> writes:
> From: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
>
> The current implementation of MCE early handling modifies CR0/1 registers
> without saving its old values. Fix this by moving early check for
> powersaving mode to machine_check_handle_early().

>>From (internal bug report) it seems as though in a test where one
injects continuous SLB Multi Hit errors, this bug could lead to rebooting
"due to to Platform error" rather than continuing to recover
successfully. It might be a good idea to mention that in commit message
here.

Also, should this go to stable?

-- 
Stewart Smith
OPAL Architect, IBM.