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Date: Sat, 21 Apr 2001 10:18:06 -0700 (PDT)
From: Linus Torvalds <torvalds@transmeta.com>
To: Russell King <rmk@arm.linux.org.uk>
cc: Andrea Arcangeli <andrea@suse.de>,
        "D . W . Howells" <dhowells@astarte.free-online.co.uk>,
        <dhowells@redhat.com>, <linux-kernel@vger.kernel.org>
Subject: Re: x86 rwsem in 2.4.4pre[234] are still buggy [was Re: rwsem
 benchmarks [Re: generic rwsem [Re: Alpha "process table hang"]]]
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On Sat, 21 Apr 2001, Russell King wrote:
>
> Erm, spin_lock()?  What if up_read or up_write gets called from interrupt
> context (is this allowed)?

Currently that is not allowed.

We allow it for regular semaphores, but not for rw-semaphores.

We may some day have to revisit that issue, but I suspect we won't have
much reason to.

		Linus

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