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Subject: Re: question on SMP and read()/write()
To: Oliver.Neukum@lrz.uni-muenchen.de (Oliver Neukum)
Date: Sat, 28 Oct 2000 17:19:18 +0100 (BST)
Cc: linux-kernel@vger.kernel.org
In-Reply-To: <00102816313507.00773@ghanima> from "Oliver Neukum" at Oct 28, 2000 04:31:35 PM
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From: Alan Cox <alan@lxorguk.ukuu.org.uk>
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> I've noticed that sys_read() and sys_write() don't grab the big kernel lock.
> As file descriptors may be shared, must device drivers provide SMP safe
> read() and write() methods ?

Yes. This is true in 2.2 as well although the inode lock provides some protection
on writes.

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