From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@arm.linux.org.uk (Russell King - ARM Linux) Date: Fri, 27 Jul 2012 22:06:37 +0100 Subject: [PATCH 1/1 v2] ARM: only call smp_send_stop() on SMP In-Reply-To: <20120727204447.GA10024@mudshark.cambridge.arm.com> References: <1340533690-4049-1-git-send-email-javier@dowhile0.org> <20120625005134.GA2342@S2101-09.ap.freescale.net> <20120625084905.GD19226@n2100.arm.linux.org.uk> <5012CC98.60206@ti.com> <20120727204447.GA10024@mudshark.cambridge.arm.com> Message-ID: <20120727210637.GA16377@n2100.arm.linux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Jul 27, 2012 at 09:44:47PM +0100, Will Deacon wrote: > On Fri, Jul 27, 2012 at 06:15:04PM +0100, Jon Hunter wrote: > > Hi Javier, > > > > On 06/25/2012 05:31 AM, Javier Martinez Canillas wrote: > > > On Mon, Jun 25, 2012 at 10:49 AM, Russell King - ARM Linux > > > wrote: > > >> On Mon, Jun 25, 2012 at 08:51:37AM +0800, Shawn Guo wrote: > > >>> It seems the same patch has been there for a while. > > >>> > > >>> http://thread.gmane.org/gmane.linux.kernel/1303115 > > >> > > >> Bah, why doesn't stuff like this get resent if nothing has happened for > > >> a while? > > > > > > Indeed. At least other people that face the same issue (like me) sends > > > similar patches to remind you :-) > > > > I checked with Russell but this one is not in his patch tracking system > > [1] and so still not queued. Can you submit this? Would be great to get > > this one in. > > I did comment on this one: > > http://thread.gmane.org/gmane.linux.kernel/1303115 > > and I really think we should fix the cause of the problem, rather than > point patching this instance of it. What do you think needs fixing there? We support booting a kernel on systems with or without SMP support, even with a SMP kernel. When the kernel is booted on such a system, it is undefined whether smp_cross_call() is a valid function pointer. In any case, when we have only one CPU online in the system, it is pointless even calling smp_cross_call(). That is why I explicitly suggested this solution. This is the solution _I_ want, because it is the most sane solution all round.