From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shaohua Li Subject: [PATCH 2/2]cpuidle: makes AMD C1E works in suspend/resume path Date: Tue, 19 May 2009 16:09:54 +0800 Message-ID: <20090519080954.GB12117@sli10-desk.sh.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mga11.intel.com ([192.55.52.93]:18638 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754142AbZESIJy (ORCPT ); Tue, 19 May 2009 04:09:54 -0400 Content-Disposition: inline Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org Cc: mingo@redhat.com, thisistempbox@yahoo.com, lenb@kernel.org When AMD C1E is enabled, local APIC timer will stop even in C1. To avoid suspend/resume hang, this patch removes C1 and replace it with a cpu_relax() in suspend/resume path. This hasn't any impact in runtime path. http://bugzilla.kernel.org/show_bug.cgi?id=13233 [ impact: avoid suspend/resume hang in AMD CPU with C1E enabled ] Tested-by: Dmitry Lyzhyn Signed-off-by: Shaohua Li --- drivers/acpi/processor_idle.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Index: linux/drivers/acpi/processor_idle.c =================================================================== --- linux.orig/drivers/acpi/processor_idle.c 2009-05-19 09:56:59.000000000 +0800 +++ linux/drivers/acpi/processor_idle.c 2009-05-19 10:01:23.000000000 +0800 @@ -834,8 +834,8 @@ static int acpi_idle_enter_c1(struct cpu /* Do not access any ACPI IO ports in suspend path */ if (acpi_idle_suspend) { - acpi_safe_halt(); local_irq_enable(); + cpu_relax(); return 0; }