From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: [PATCH] seqlock: serialize against writers
Date: Fri, 29 Aug 2008 19:08:51 +0200
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Cc: Andi Kleen <andi@firstfloor.org>,
	Gregory Haskins <gregory.haskins@gmail.com>, mingo@elte.hu,
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No idea on the problem itself because I don't understand it, just:

> Given that, we either need to address the const requirement
> for userspace, alter userspace's usage, or find another way to address
> the deadlock.  Any ideas?

In the worst case you can always disable the vsyscall gtod() and
thus the need for a user space safe seqlock_t, but it will
hurt some workloads significantly. 

-Andi