From: Janice M. Girouard <jgirouar@redhat.com>
Subject: RHEL 5.0 PPC PATCH] DLPAR virtual CPU removal failure - cppr bits
Date: Mon, 18 Dec 2006 17:42:06 -0500 (Eastern Standard Time)
Bugzilla: 218058
Message-Id: <Pine.WNT.4.64.0612181739410.2100@IBM-3MTQI3AXJFW>
Changelog: ppc64: DLPAR virtual CPU removal failure - cppr bits


RHBZ#: 218058
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=218058

Description:
------------
drslot tools do not correctly handle a RTAS failure.  The end result is that customers are unable to remove virtual CPU's. 

Currently,the drslot tool returns "success" even when the RTAS call fails.  This leaves the HMC and the partition in one state, while phyp is in 
another.  The tool should return a failure code, and the HMC will display the reason for the failure.  

RHEL Version Found:
-------------------
RHEL 5.0 alpha

Upstream Status:
----------------
This patch is not upstream.  The real fix for this bug more complicated and risky than what is suitable for acceptance at this stage in a release.  
This patch has been informally approved by benh who will also be writing the larger (and much more complicated) fix that will be submitted 
upstream.


Test Status:
------------
This patch was tested by Nathan Fontenot of IBM.  This patch builds 
cleanly against kernel-2.6.18-1.2839.el5.

Proposed Patch:
----------------
Please review and ACK for RHEL 5.0

--- linux-2.6.18.ppc64/arch/powerpc/platforms/pseries/.xics.c	2006-11-30 15:35:22.000000000 -0600
+++ linux-2.6.18.ppc64/arch/powerpc/platforms/pseries/xics.c	2006-11-30 15:35:51.000000000 -0600
@@ -788,8 +788,10 @@ void xics_teardown_cpu(int secondary)
 	if (ipi == XICS_IRQ_SPURIOUS)
 		return;
 	desc = get_irq_desc(ipi);
-	if (desc->chip && desc->chip->eoi)
+	if (desc->chip && desc->chip->eoi) {
 		desc->chip->eoi(ipi);
+		xics_set_cpu_priority(cpu, 0);
+	}
 
 	/*
 	 * Some machines need to have at least one cpu in the GIQ,