Patch "powerpc/pseries: Release DRC when configure_connector fails" has been added to the 4.2-stable tree

Patch "powerpc/pseries: Release DRC when configure_connector fails" has been added to the 4.2-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    powerpc/pseries: Release DRC when configure_connector fails

to the 4.2-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     powerpc-pseries-release-drc-when-configure_connector-fails.patch
and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From daebaabb5cfbe4a6f09ca0e0f8b7673efc704960 Mon Sep 17 00:00:00 2001
From: Bharata B Rao <bharata@linux.vnet.ibm.com>
Date: Mon, 7 Sep 2015 15:52:40 +0530
Subject: powerpc/pseries: Release DRC when configure_connector fails

From: Bharata B Rao <bharata@linux.vnet.ibm.com>

commit daebaabb5cfbe4a6f09ca0e0f8b7673efc704960 upstream.

Commit f32393c943e2 ("powerpc/pseries: Correct cpu affinity for
dlpar added cpus") moved dlpar_acquire_drc() call to before
dlpar_configure_connector() call in dlpar_cpu_probe(), but missed
to release the DRC if dlpar_configure_connector() failed.
During CPU hotplug, if configure-connector fails for any reason,
then this will result in subsequent CPU hotplug attempts to fail.

Release the acquired DRC if dlpar_configure_connector() call fails
so that the DRC is left in right isolation and allocation state
for the subsequent hotplug operation to succeed.

Fixes: f32393c943e2 ("powerpc/pseries: Correct cpu affinity for dlpar added cpus")
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/powerpc/platforms/pseries/dlpar.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/arch/powerpc/platforms/pseries/dlpar.c
+++ b/arch/powerpc/platforms/pseries/dlpar.c
@@ -422,8 +422,10 @@ static ssize_t dlpar_cpu_probe(const cha
 
 	dn = dlpar_configure_connector(cpu_to_be32(drc_index), parent);
 	of_node_put(parent);
-	if (!dn)
+	if (!dn) {
+		dlpar_release_drc(drc_index);
 		return -EINVAL;
+	}
 
 	rc = dlpar_attach_node(dn);
 	if (rc) {


Patches currently in stable-queue which might be from bharata@linux.vnet.ibm.com are

queue-4.2/powerpc-pseries-release-drc-when-configure_connector-fails.patch