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Date: Thu, 14 Jun 2001 19:47:57 +0200
From: Andrea Arcangeli <andrea@suse.de>
To: Richard Henderson <rth@redhat.com>
Cc: Linus Torvalds <torvalds@transmeta.com>, Ingo Molnar <mingo@elte.hu>,
        linux-kernel@vger.kernel.org
Subject: Re: unregistered changes to the user<->kernel API
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In-Reply-To: <20010614103249.A28852@redhat.com>; from rth@redhat.com on Thu, Jun 14, 2001 at 10:32:49AM -0700
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On Thu, Jun 14, 2001 at 10:32:49AM -0700, Richard Henderson wrote:
> within glibc, and (2) making these accesses slower since they
> will be considered O_DIRECT after the change.

and then read/write will return -EINVAL which is life-threatening.
O_DIRECT like rawio via /dev/raw imposes special buffer size and
alignment (size multiple of softblocksize of the fs and softblocksize
alignment, at max I can turn it down to hardblocksize without intensive
changes and guaranteeing zerocopy [modulo bounce buffers on x86 of
course]).

So in short at least glibc would need to be replaced...

Andrea