Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754632AbZDOEoX (ORCPT ); Wed, 15 Apr 2009 00:44:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752201AbZDOEoO (ORCPT ); Wed, 15 Apr 2009 00:44:14 -0400 Received: from ozlabs.org ([203.10.76.45]:51866 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752328AbZDOEoN (ORCPT ); Wed, 15 Apr 2009 00:44:13 -0400 From: Rusty Russell To: Hugh Dickins Subject: Re: [PATCH] x86 microcode: revert some work_on_cpu Date: Wed, 15 Apr 2009 14:14:07 +0930 User-Agent: KMail/1.11.2 (Linux/2.6.28-11-generic; KDE/4.2.2; i686; ; ) Cc: Linus Torvalds , Andrew Morton , Ingo Molnar , Dmitry Adamushko , Peter Oruba , Arjan van de Ven , linux-kernel@vger.kernel.org References: In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200904151414.09119.rusty@rustcorp.com.au> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1254 Lines: 30 On Wed, 15 Apr 2009 03:55:42 am Hugh Dickins wrote: > Revert part of af5c820a3169e81af869c113e18ec7588836cd50 > x86: cpumask: use work_on_cpu in arch/x86/kernel/microcode_core.c > > That change is causing only one Intel CPU's microcode to be updated e.g. > microcode: CPU3 updated from revision 0x9 to 0x17, date = 2005-04-22 > where before it announced that also for CPU0 and CPU1 and CPU2. > > We cannot use work_on_cpu() in the CONFIG_MICROCODE_OLD_INTERFACE code, > because Intel's request_microcode_user() involves a copy_from_user() from > /sbin/microcode_ctl, which therefore needs to be on that CPU at the time. Erk. Ack the reversion, but this needs to be fixed properly. We can't just mug a process's affinity. I'll look at this code again and see what I can do. > May be not the only problem with that commit: I've seen lockdep > warnings from s2ram when suspending; but I think there have been other > work_on_cpu() lockdep issues, and you may already be on to them? Yep. Thanks, Rusty. -- 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/