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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

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.
--
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/