From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e36.co.us.ibm.com (e36.co.us.ibm.com [32.97.110.154]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e36.co.us.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTP id 08BB1DDF1E for ; Wed, 7 Mar 2007 00:58:19 +1100 (EST) Received: from westrelay02.boulder.ibm.com (westrelay02.boulder.ibm.com [9.17.195.11]) by e36.co.us.ibm.com (8.13.8/8.13.8) with ESMTP id l26DwGKR011717 for ; Tue, 6 Mar 2007 08:58:16 -0500 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by westrelay02.boulder.ibm.com (8.13.8/8.13.8/NCO v8.3) with ESMTP id l26DwG0A554396 for ; Tue, 6 Mar 2007 06:58:16 -0700 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id l26DwFas010895 for ; Tue, 6 Mar 2007 06:58:16 -0700 Date: Tue, 6 Mar 2007 19:27:54 +0530 From: Mohan Kumar M To: Paul Mackerras Subject: Re: [PATCH] Fix interrupt distribution in ppc970 Message-ID: <20070306135754.GB7476@in.ibm.com> References: <20061208045537.GA14626@in.ibm.com> <17798.6928.378248.28903@cargo.ozlabs.ibm.com> <20061218105706.GB3911@in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20061218105706.GB3911@in.ibm.com> Cc: ppcdev , fastboot@lists.osdl.org Reply-To: mohan@in.ibm.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi, Here comes the revised version of patch to fix the interrupt missing problem when a kdump kernel is booted with "maxcpus=1" kernel parameter. In the xics initialization code a check is made to detemine whether maxcpus kernel parameter is present and if its present then default_distrib_server variable is initialized to the current boot cpu id (by default_server variable). So that when ever a kernel is booted with maxcpus kernel parameter all interrupts are routed to the boot cpu only. Tested on POWER5 and JS20 systems. Any comment? Signed-off-by: Mohan Kumar M --- arch/powerpc/platforms/pseries/xics.c | 7 +++++++ 1 file changed, 7 insertions(+) Index: linux-2.6.20/arch/powerpc/platforms/pseries/xics.c =================================================================== --- linux-2.6.20.orig/arch/powerpc/platforms/pseries/xics.c +++ linux-2.6.20/arch/powerpc/platforms/pseries/xics.c @@ -734,6 +734,13 @@ void __init xics_init_IRQ(void) skip_gserver_check: of_node_put(np); + /* Kdump with maxcpus parameter in PPC970xx creates interrupt + * distribution problems. So assign current boot cpu id to + * interrupt distribution server + */ + if (strstr(saved_command_line, "maxcpus=")) + default_distrib_server = default_server; + if (firmware_has_feature(FW_FEATURE_LPAR)) ppc_md.get_irq = xics_get_irq_lpar; else