From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752075AbbJGIUK (ORCPT ); Wed, 7 Oct 2015 04:20:10 -0400 Received: from gate.crashing.org ([63.228.1.57]:59600 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751275AbbJGIUG (ORCPT ); Wed, 7 Oct 2015 04:20:06 -0400 Date: Wed, 7 Oct 2015 02:19:11 -0500 From: Segher Boessenkool To: Michael Ellerman Cc: Laura Abbott , Paul Mackerras , "linuxppc-dev@lists.ozlabs.org" , Linux Kernel Mailing List Subject: Re: Missing operand for tlbie instruction on Power7 Message-ID: <20151007071911.GA31002@gate.crashing.org> References: <560EA623.1040300@redhat.com> <1444102518.16909.3.camel@ellerman.id.au> <56141237.2040403@redhat.com> <1444197649.6794.7.camel@ellerman.id.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1444197649.6794.7.camel@ellerman.id.au> User-Agent: Mutt/1.4.2.3i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 07, 2015 at 05:00:49PM +1100, Michael Ellerman wrote: > > It's also worth noting that the __flush_power7 uses tlbiel instead of tlbie. > > Yeah that's a good point. It's not clear if the swsusp code wants to a local or > a global invalidate. If I read the code right, this is called on the boot CPU when all the non-boot CPUs are still (potentially) down, so if you would do a global invalidate the non-boot CPUs might not even notice, so those need to do a (local) invalidate after being brought up anyway? Or they probably need it before being brought down at all? You figure it out, it makes my brain hurt :-) > As an alternative, can you try adding a .machine push / .machine "power4" / > .machine pop, around the tlbie. That should tell the assembler to drop back to > power4 mode for that instruction, which should then do the right thing. There > are some examples in that file. That will get the assembler to not complain, but it will assemble the wrong instruction: the power7 instruction has the same opcode (but different semantics). So if you assemble a "tlbie r4" in power4 mode, a newer CPU will see it as a "tlbie r4,r0" and do the wrong thing. Segher