lkml.org 
[lkml]   [2014]   [Apr]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v4 3/5] acpi_processor: do not mark present at boot but not onlined CPU as onlined
Date
acpi_processor_add() assumes that present at boot CPUs
are always onlined, it is not so if a CPU failed to become
onlined. As result acpi_processor_add() will mark such CPU
device as onlined in sysfs and following attempts to
online/offline it using /sys/device/system/cpu/cpuX/online
attribute will fail.

Do not poke into device internals in acpi_processor_add()
and touch "struct device { .offline }" attribute, since
for CPUs onlined at boot it's set by:
topology_init() -> arch_register_cpu() -> register_cpu()
before ACPI device tree is parsed, and for hotplugged
CPUs it's set when userspace onlines CPU via sysfs.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
---
v2:
- fix regression in v1 leading to NULL pointer dereference
on CPU unplug, do not remove "pr->dev = dev;"
---
drivers/acpi/acpi_processor.c | 1 -
1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index c29c2c3..42d66f8 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -404,7 +404,6 @@ static int acpi_processor_add(struct acpi_device *device,
goto err;

pr->dev = dev;
- dev->offline = pr->flags.need_hotplug_init;

/* Trigger the processor driver's .probe() if present. */
if (device_attach(dev) >= 0)
--
1.7.1


\
 
 \ /
  Last update: 2014-04-14 19:21    [W:0.142 / U:42.512 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site