linux-kernel - Re: [PATCH 4/6] x86-mce: Add spinlocks to prevent duplicated MCP and CMCI reports.

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Message-ID: <20140710191224.GF5603@pd.tnic>
Date:	Thu, 10 Jul 2014 21:12:24 +0200
From:	Borislav Petkov <bp@...en8.de>
To:	Tony Luck <tony.luck@...il.com>
Cc:	Havard Skinnemoen <hskinnemoen@...gle.com>,
	Linux Kernel <linux-kernel@...r.kernel.org>,
	Ewout van Bekkum <ewout@...gle.com>
Subject: Re: [PATCH 4/6] x86-mce: Add spinlocks to prevent duplicated MCP and
 CMCI reports.

On Thu, Jul 10, 2014 at 11:57:06AM -0700, Tony Luck wrote:
> You don't know if the bank is shared or not. If it is not shared, then
> the above code might skip reading the bank because some other cpu is
> busy reading that bank number - and seeing its own private bank.

Grrr, I see what you mean.

Hmm, can we serialize machine_check_poll per CPU in a cheaper way?
Disabling interrupts around the reads is certainly fine but still too
heavy-handed IMO.

I'll think about it more tomorrow - my brain is twisted enough for
today. :-)

-- 
Regards/Gruss,
    Boris.

Sent from a fat crate under my desk. Formatting is fine.
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