Subject: Re: [PATCH] cryptoapi: Fix sleeping
From: Robert Love <rml@tech9.net>
To: Matt Mackall <mpm@selenic.com>
Cc: Jeff Garzik <jgarzik@pobox.com>, James Morris <jmorris@intercode.com.au>,
       "David S. Miller" <davem@redhat.com>,
       linux-kernel <linux-kernel@vger.kernel.org>
In-Reply-To: <20030814015820.GH325@waste.org>
References: <20030813233957.GE325@waste.org> <3F3AD5F1.8000901@pobox.com>
	 <1060821251.4709.449.camel@lettuce>  <20030814015820.GH325@waste.org>
Content-Type: text/plain
Message-Id: <1060878560.4709.474.camel@lettuce>
Mime-Version: 1.0
Date: Thu, 14 Aug 2003 09:29:20 -0700
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 901
Lines: 24

On Wed, 2003-08-13 at 18:58, Matt Mackall wrote:

> This is part of cryptoapi and given the large chunks of work you could
> potentially hand to it, it's probably a good idea for it to work this
> way. You hand it a long list of sg segments, it does the transform and
> reschedules if it thinks it's safe. But its test of when it was safe
> was not complete.

Right.  My concern is that you said sometimes it is called when
preemption is disabled.

I assume because it is accessing per-processor data.

It is illegal to reschedule -- regardless of kernel preemption -- while
in the middle of a critical section accessing per-processor data.

	Robert Love


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/