[PATCH] powerpc/pseries: dynamically added OF nodes need to call of_node_init

[PATCH] powerpc/pseries: dynamically added OF nodes need to call of_node_init

[Tyrel Datwyler]

Commit 75b57ecf9 refactored device tree nodes to use kobjects such that they
can be exposed via /sysfs. A secondary commit 0829f6d1f furthered this rework
by moving the kobect initialization logic out of of_node_add into its own
of_node_init function. The inital commit removed the existing kref_init calls
in the pseries dlpar code with the assumption kobject initialization would
occur in of_node_add. The second commit had the side effect of triggering a
BUG_ON as a result of dynamically added nodes being uninitialized.

This patch fixes this by adding of_node_init calls in place of the previously
removed kref_init calls.

Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/pseries/dlpar.c    | 1 +
 arch/powerpc/platforms/pseries/reconfig.c | 1 +
 2 files changed, 2 insertions(+)

diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
index 022b38e..2d0b4d6 100644
--- a/arch/powerpc/platforms/pseries/dlpar.c
+++ b/arch/powerpc/platforms/pseries/dlpar.c
@@ -86,6 +86,7 @@ static struct device_node *dlpar_parse_cc_node(struct cc_workarea *ccwa,
 	}
 
 	of_node_set_flag(dn, OF_DYNAMIC);
+	of_node_init(dn);
 
 	return dn;
 }
diff --git a/arch/powerpc/platforms/pseries/reconfig.c b/arch/powerpc/platforms/pseries/reconfig.c
index 0435bb6..1c0a60d 100644
--- a/arch/powerpc/platforms/pseries/reconfig.c
+++ b/arch/powerpc/platforms/pseries/reconfig.c
@@ -69,6 +69,7 @@ static int pSeries_reconfig_add_node(const char *path, struct property *proplist
 
 	np->properties = proplist;
 	of_node_set_flag(np, OF_DYNAMIC);
+	of_node_init(np);
 
 	np->parent = derive_parent(path);
 	if (IS_ERR(np->parent)) {
-- 
1.7.12.4

Re: [PATCH] powerpc/pseries: dynamically added OF nodes need to call of_node_init

[Michael Ellerman]

On Wed, 2014-07-09 at 21:20 -0400, Tyrel Datwyler wrote:
> Commit 75b57ecf9 refactored device tree nodes to use kobjects such that they
> can be exposed via /sysfs. A secondary commit 0829f6d1f furthered this rework
> by moving the kobect initialization logic out of of_node_add into its own
> of_node_init function. The inital commit removed the existing kref_init calls
> in the pseries dlpar code with the assumption kobject initialization would
> occur in of_node_add. The second commit had the side effect of triggering a
> BUG_ON as a result of dynamically added nodes being uninitialized.

So does this mean DLPAR is broken since 0829f6d1f (3.15-rc1)?

If so this should have a Cc: stable@kernel.org shouldn't it?

And the latest trend is to also add:

Fixes: 0829f6d1f69e ("of: device_node kobject lifecycle fixes")

cheers

Re: [PATCH] powerpc/pseries: dynamically added OF nodes need to call of_node_init

[Nathan Fontenot]

On 07/09/2014 09:33 PM, Michael Ellerman wrote:
> On Wed, 2014-07-09 at 21:20 -0400, Tyrel Datwyler wrote:
>> Commit 75b57ecf9 refactored device tree nodes to use kobjects such that they
>> can be exposed via /sysfs. A secondary commit 0829f6d1f furthered this rework
>> by moving the kobect initialization logic out of of_node_add into its own
>> of_node_init function. The inital commit removed the existing kref_init calls
>> in the pseries dlpar code with the assumption kobject initialization would
>> occur in of_node_add. The second commit had the side effect of triggering a
>> BUG_ON as a result of dynamically added nodes being uninitialized.
> 
> So does this mean DLPAR is broken since 0829f6d1f (3.15-rc1)?

Yes. Partition migration would also be affected by this.

-Nathan

> 
> If so this should have a Cc: stable@kernel.org shouldn't it?
> 
> And the latest trend is to also add:
> 
> Fixes: 0829f6d1f69e ("of: device_node kobject lifecycle fixes")
> 
> cheers
> 
> 

Re: [PATCH] powerpc/pseries: dynamically added OF nodes need to call of_node_init

[Tyrel Datwyler]

On 07/09/2014 07:33 PM, Michael Ellerman wrote:
> On Wed, 2014-07-09 at 21:20 -0400, Tyrel Datwyler wrote:
>> Commit 75b57ecf9 refactored device tree nodes to use kobjects such that they
>> can be exposed via /sysfs. A secondary commit 0829f6d1f furthered this rework
>> by moving the kobect initialization logic out of of_node_add into its own
>> of_node_init function. The inital commit removed the existing kref_init calls
>> in the pseries dlpar code with the assumption kobject initialization would
>> occur in of_node_add. The second commit had the side effect of triggering a
>> BUG_ON as a result of dynamically added nodes being uninitialized.
> 
> So does this mean DLPAR is broken since 0829f6d1f (3.15-rc1)?

Yes, as well as suspend and migration.

> 
> If so this should have a Cc: stable@kernel.org shouldn't it?

Doh, right you are.

> 
> And the latest trend is to also add:
> 
> Fixes: 0829f6d1f69e ("of: device_node kobject lifecycle fixes")

Got it. Will resend v2.

-Tyrel

> 
> cheers
> 
> 
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