Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751225AbWADJdk (ORCPT ); Wed, 4 Jan 2006 04:33:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751228AbWADJdk (ORCPT ); Wed, 4 Jan 2006 04:33:40 -0500 Received: from e31.co.us.ibm.com ([32.97.110.149]:26567 "EHLO e31.co.us.ibm.com") by vger.kernel.org with ESMTP id S1751225AbWADJdj (ORCPT ); Wed, 4 Jan 2006 04:33:39 -0500 Date: Wed, 4 Jan 2006 15:03:20 +0530 From: Vivek Goyal To: Morton Andrew Morton Cc: "Eric W. Biederman" , linux kernel mailing list , Fastboot mailing list , Andi Kleen Subject: [PATCH 1/2] x86_64: ioapic virtual wire mode fix Message-ID: <20060104093320.GA4995@in.ibm.com> Reply-To: vgoyal@in.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1651 Lines: 38 o Currently, during kexec reboot, IOAPIC is re-programmed back to virtual wire mode if there was an i8259 connected to it. This enables getting timer interrupts in second kernel in legacy mode. o After putting into virtual wire mode, IOAPIC delivers the i8259 interrupts to CPU0. This works well for kexec but not for kdump as we might crash on a different CPU and second kernel will not see timer interrupts. o This patch modifies the redirection table entry to deliver the timer interrupts to the cpu we are rebooting (instead of hardcoding to zero). This ensures that second kernel receives timer interrupts even on a non-boot cpu. Signed-off-by: Vivek Goyal --- diff -puN arch/x86_64/kernel/io_apic.c~kdump-x86_64-program-ioapic-non-boot-cpu-timer-interrupts arch/x86_64/kernel/io_apic.c --- linux-2.6.15/arch/x86_64/kernel/io_apic.c~kdump-x86_64-program-ioapic-non-boot-cpu-timer-interrupts 2006-01-04 05:12:48.000000000 -0800 +++ linux-2.6.15-root/arch/x86_64/kernel/io_apic.c 2006-01-04 06:55:42.000000000 -0800 @@ -1245,8 +1245,8 @@ void disable_IO_APIC(void) entry.dest_mode = 0; /* Physical */ entry.delivery_mode = 7; /* ExtInt */ entry.vector = 0; - entry.dest.physical.physical_dest = 0; - + entry.dest.physical.physical_dest = + GET_APIC_ID(apic_read(APIC_ID)); /* * Add it to the IO-APIC irq-routing table: _ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/