Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965270Ab1C3VJ7 (ORCPT ); Wed, 30 Mar 2011 17:09:59 -0400 Received: from mga02.intel.com ([134.134.136.20]:44838 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965229Ab1C3VJv (ORCPT ); Wed, 30 Mar 2011 17:09:51 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.63,270,1299484800"; d="scan'208";a="621238913" From: Andi Kleen References: <20110330203.501921634@firstfloor.org> In-Reply-To: <20110330203.501921634@firstfloor.org> To: stuart_hayes@yahoo.com, douglas_warzecha@dell.com, ak@linux.intel.com, cebbert@redhat.com, jkosina@suse.cz, gregkh@suse.de, linux-kernel@vger.kernel.org, stable@kernel.org, tim.bird@am.sony.com Subject: [PATCH] [242/275] dcdbas: force SMI to happen when expected Message-Id: <20110330210808.823D93E1A05@tassilo.jf.intel.com> Date: Wed, 30 Mar 2011 14:08:08 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1786 Lines: 45 2.6.35-longterm review patch. If anyone has any objections, please let me know. ------------------ From: Stuart Hayes commit dd65c736d1b5312c80c88a64bf521db4959eded5 upstream. The dcdbas driver can do an I/O write to cause a SMI to occur. The SMI handler looks at certain registers and memory locations, so the SMI needs to happen immediately. On some systems I/O writes are posted, though, causing the SMI to happen well after the "outb" occurred, which causes random failures. Following the "outb" with an "inb" forces the write to go through even if it is posted. Signed-off-by: Stuart Hayes Acked-by: Doug Warzecha Signed-off-by: Andi Kleen Cc: Chuck Ebbert Signed-off-by: Jiri Kosina Signed-off-by: Greg Kroah-Hartman --- drivers/firmware/dcdbas.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) Index: linux-2.6.35.y/drivers/firmware/dcdbas.c =================================================================== --- linux-2.6.35.y.orig/drivers/firmware/dcdbas.c 2011-03-29 22:50:16.283841755 -0700 +++ linux-2.6.35.y/drivers/firmware/dcdbas.c 2011-03-29 23:03:03.249217032 -0700 @@ -268,8 +268,10 @@ } /* generate SMI */ + /* inb to force posted write through and make SMI happen now */ asm volatile ( - "outb %b0,%w1" + "outb %b0,%w1\n" + "inb %w1" : /* no output args */ : "a" (smi_cmd->command_code), "d" (smi_cmd->command_address), -- 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/