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Date: Mon, 13 Oct 2008 16:40:00 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Ingo Molnar <mingo@elte.hu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
       Karel Zak <kzak@redhat.com>, Arjan van de Ven <arjan@infradead.org>,
       Andrew Morton <akpm@linux-foundation.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Nick Piggin <nickpiggin@yahoo.com.au>,
       Thomas Gleixner <tglx@linutronix.de>, "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [kerneloops] regression in 2.6.27 wrt "lock_page" and the
 "hwclock" program
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> The warning occurs because hwclock uses this dubious sequence of
> code to run "atomic" code:

Nobody should be using old versions of hwclock that do this as they are
not SMP safe.

> So instead just enable interrupts in the pagefault path unconditionally
> if we come from user-space, and handle the fault.

This should definitely also log an error to get users to remove that
rubbish from their PC