From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH 00/14] Fix issues with ARMv6+v6k+v7 kernels Date: Fri, 11 Feb 2011 21:07:33 +0000 Message-ID: <20110211210733.GC31529@n2100.arm.linux.org.uk> References: <20110117192050.GE23331@n2100.arm.linux.org.uk> <0557426516de482c1769a50fa0b5f17a@mail.gmail.com> <20110208164747.GD6188@n2100.arm.linux.org.uk> <20110210130430.GB3652@n2100.arm.linux.org.uk> <1297343555.9306.9.camel@e102109-lin.cambridge.arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from caramon.arm.linux.org.uk ([78.32.30.218]:47310 "EHLO caramon.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758107Ab1BKVHw (ORCPT ); Fri, 11 Feb 2011 16:07:52 -0500 Content-Disposition: inline In-Reply-To: Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Nicolas Pitre Cc: Catalin Marinas , Santosh Shilimkar , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org On Fri, Feb 11, 2011 at 03:45:51PM -0500, Nicolas Pitre wrote: > The patch below is making the code more straight forward regardless of > any swp emulation issues. I don't know where you get that idea from. What it does is make a kernel built with a standard set of options have differing behaviour on v7 and pre-v7 architectures. On v7 architectures, the vectors page and user pages all become read only to SVC mode. On pre-v7 architectures on the same kernel, they are read- write to SVC mode. What we have now is that these pages are only read-only when CPU domains are turned off - for everything. So we know that if CPU domains are enabled, it's read/write, otherwise it's read only. That's more straight forward than what this patch creates IMHO. From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@arm.linux.org.uk (Russell King - ARM Linux) Date: Fri, 11 Feb 2011 21:07:33 +0000 Subject: [PATCH 00/14] Fix issues with ARMv6+v6k+v7 kernels In-Reply-To: References: <20110117192050.GE23331@n2100.arm.linux.org.uk> <0557426516de482c1769a50fa0b5f17a@mail.gmail.com> <20110208164747.GD6188@n2100.arm.linux.org.uk> <20110210130430.GB3652@n2100.arm.linux.org.uk> <1297343555.9306.9.camel@e102109-lin.cambridge.arm.com> Message-ID: <20110211210733.GC31529@n2100.arm.linux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Feb 11, 2011 at 03:45:51PM -0500, Nicolas Pitre wrote: > The patch below is making the code more straight forward regardless of > any swp emulation issues. I don't know where you get that idea from. What it does is make a kernel built with a standard set of options have differing behaviour on v7 and pre-v7 architectures. On v7 architectures, the vectors page and user pages all become read only to SVC mode. On pre-v7 architectures on the same kernel, they are read- write to SVC mode. What we have now is that these pages are only read-only when CPU domains are turned off - for everything. So we know that if CPU domains are enabled, it's read/write, otherwise it's read only. That's more straight forward than what this patch creates IMHO.