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Date: Mon, 8 Sep 2014 20:17:22 +0100
From: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
To: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: bit fields && data tearing
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Cc: Jakub Jelinek <jakub@redhat.com>,
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> > I think the whole "removing Alpha EV5" support is basically bonkers. Just
> > use set_bit in the tty layer. Alpha will continue to work as well as it
> > always has done and you won't design out support for any future processor
> > that turns out not to do byte aligned stores.
> > 
> > Alan
> > 
> 
> Is *that* what we are talking about?  I was added to this conversation
> in the middle where it had already generalized, so I had no idea.
> 
> 	-hpa

Yes there are some flags in the tty layer that are vulnerable to this
(although they've been vulnerable to it and missing a lock since last
century with no known ill effects).

It's not as if this is causing any work to anyone beyond using the
standard API, no API needs to change.

Alan