[patch 40/87] cpuidle: fix AMD C1E suspend hang

Greg KH
2009-06-09T10:26:33Z

[-- Attachment #1: cpuidle-fix-amd-c1e-suspend-hang.patch --]
[-- Type: text/plain, Size: 1123 bytes --]

2.6.29-stable review patch. If anyone has any objections, please let us know.

------------------

From: Shaohua Li <shaohua.li@intel.com>

commit 7d60e8ab0d5507229dfbdf456501cc378610fa01 upstream.

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 <thisistempbox@yahoo.com>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/acpi/processor_idle.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -870,8 +870,8 @@ 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;
}