[PATCH 3.12 198/206] powerpc: use device_online/offline() instead of cpu_up/down()

From: Jiri Slaby
Date: Tue Nov 18 2014 - 09:13:16 EST

From: Dan Streetman <ddstreet@xxxxxxxx>

3.12-stable review patch. If anyone has any objections, please let me know.


commit 10ccaf178b2b961d8bca252d647ed7ed8aae2a20 upstream.

In powerpc pseries platform dlpar operations, use device_online() and
device_offline() instead of cpu_up() and cpu_down().

Calling cpu_up/down() directly does not update the cpu device offline
field, which is used to online/offline a cpu from sysfs. Calling
device_online/offline() instead keeps the sysfs cpu online value
correct. The hotplug lock, which is required to be held when calling
device_online/offline(), is already held when dlpar_online/offline_cpu()
are called, since they are called only from cpu_probe|release_store().

This patch fixes errors on phyp (PowerVM) systems that have cpu(s)
added/removed using dlpar operations; without this patch, the
/sys/devices/system/cpu/cpuN/online nodes do not correctly show the
online state of added/removed cpus.

Signed-off-by: Dan Streetman <ddstreet@xxxxxxxx>
Cc: Nathan Fontenot <nfont@xxxxxxxxxxxxxxxxxx>
Fixes: 0902a9044fa5 ("Driver core: Use generic offline/online for CPU offline/online")
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
arch/powerpc/platforms/pseries/dlpar.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
index 7cfdaae1721a..679df556f4ab 100644
--- a/arch/powerpc/platforms/pseries/dlpar.c
+++ b/arch/powerpc/platforms/pseries/dlpar.c
@@ -380,7 +380,7 @@ static int dlpar_online_cpu(struct device_node *dn)
- rc = cpu_up(cpu);
+ rc = device_online(get_cpu_device(cpu));
if (rc)
goto out;
@@ -471,7 +471,7 @@ static int dlpar_offline_cpu(struct device_node *dn)
if (get_cpu_current_state(cpu) == CPU_STATE_ONLINE) {
set_preferred_offline_state(cpu, CPU_STATE_OFFLINE);
- rc = cpu_down(cpu);
+ rc = device_offline(get_cpu_device(cpu));
if (rc)
goto out;

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