Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932792AbXASRMd (ORCPT ); Fri, 19 Jan 2007 12:12:33 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932684AbXASRMd (ORCPT ); Fri, 19 Jan 2007 12:12:33 -0500 Received: from usea-naimss1.unisys.com ([192.61.61.103]:2951 "EHLO usea-naimss1.unisys.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932792AbXASRMc (ORCPT ); Fri, 19 Jan 2007 12:12:32 -0500 Subject: [PATCH 2.6.19.2 1/1] kexec: update IO-APIC dest field to 8-bit for xAPIC From: Benjamin Romer To: LKML Cc: "Eric W. Biederman" , Vivek Goyal Content-Type: text/plain Organization: Unisys Corporation Date: Fri, 19 Jan 2007 12:12:28 -0500 Message-Id: <1169226749.6467.14.camel@ustr-romerbm-2.na.uis.unisys.com> Mime-Version: 1.0 X-Mailer: Evolution 2.8.2.1 (2.8.2.1-3.fc6) Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 19 Jan 2007 17:12:29.0845 (UTC) FILETIME=[001BAC50:01C73BED] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6005 Lines: 178 On the Unisys ES7000/ONE system, we encountered a problem where performing a kexec reboot or dump on any cell other than cell 0 causes the system timer to stop working, resulting in a hang during timer calibration in the new kernel. We traced the problem to one line of code in disable_IO_APIC(), which needs to restore the timer's IO-APIC configuration before rebooting. The code is currently using the 4-bit physical destination field, rather than using the 8-bit logical destination field, and it cuts off the upper 4 bits of the timer's APIC ID. If we change this to use the logical destination field, the timer works and we can kexec on the upper cells. This was tested on two different cells (0 and 2) in an ES7000/ONE system. For reference, the relevant Intel xAPIC spec is kept at ftp://download.intel.com/design/chipsets/e8501/datashts/30962001.pdf, specifically on page 334. Signed-off-by: Benjamin M Romer --- arch/x86_64/kernel/io_apic.c | 24 +++++++++++------------- include/asm-x86_64/io_apic.h | 38 ++++++++++++++------------------------ 2 files changed, 25 insertions(+), 37 deletions(-) diff -ru linux-2.6.19.2-orig/arch/x86_64/kernel/io_apic.c linux-2.6.19.2/arch/x86_64/kernel/io_apic.c --- linux-2.6.19.2-orig/arch/x86_64/kernel/io_apic.c 2007-03-18 12:29:52.000000000 -0400 +++ linux-2.6.19.2/arch/x86_64/kernel/io_apic.c 2007-03-18 13:15:26.000000000 -0400 @@ -814,7 +814,7 @@ entry.delivery_mode = INT_DELIVERY_MODE; entry.dest_mode = INT_DEST_MODE; entry.mask = 0; /* enable IRQ */ - entry.dest.logical.logical_dest = cpu_mask_to_apicid(TARGET_CPUS); + entry.dest = cpu_mask_to_apicid(TARGET_CPUS); idx = find_irq_entry(apic,pin,mp_INT); if (idx == -1) { @@ -832,7 +832,7 @@ if (irq_trigger(idx)) { entry.trigger = 1; entry.mask = 1; - entry.dest.logical.logical_dest = cpu_mask_to_apicid(TARGET_CPUS); + entry.dest = cpu_mask_to_apicid(TARGET_CPUS); } irq = pin_2_irq(idx, apic, pin); @@ -847,7 +847,7 @@ if (vector < 0) continue; - entry.dest.logical.logical_dest = cpu_mask_to_apicid(mask); + entry.dest = cpu_mask_to_apicid(mask); entry.vector = vector; ioapic_register_intr(irq, vector, IOAPIC_AUTO); @@ -888,7 +888,7 @@ */ entry.dest_mode = INT_DEST_MODE; entry.mask = 0; /* unmask IRQ now */ - entry.dest.logical.logical_dest = cpu_mask_to_apicid(TARGET_CPUS); + entry.dest = cpu_mask_to_apicid(TARGET_CPUS); entry.delivery_mode = INT_DELIVERY_MODE; entry.polarity = 0; entry.trigger = 0; @@ -988,18 +988,17 @@ printk(KERN_DEBUG ".... IRQ redirection table:\n"); - printk(KERN_DEBUG " NR Log Phy Mask Trig IRR Pol" - " Stat Dest Deli Vect: \n"); + printk(KERN_DEBUG " NR Dst Mask Trig IRR Pol" + " Stat Dmod Deli Vect: \n"); for (i = 0; i <= reg_01.bits.entries; i++) { struct IO_APIC_route_entry entry; entry = ioapic_read_entry(apic, i); - printk(KERN_DEBUG " %02x %03X %02X ", + printk(KERN_DEBUG " %02x %03X ", i, - entry.dest.logical.logical_dest, - entry.dest.physical.physical_dest + entry.dest ); printk("%1d %1d %1d %1d %1d %1d %1d %02X\n", @@ -1261,8 +1260,7 @@ entry.dest_mode = 0; /* Physical */ entry.delivery_mode = dest_ExtINT; /* ExtInt */ entry.vector = 0; - entry.dest.logical.logical_dest = - GET_APIC_ID(apic_read(APIC_ID)); + entry.dest = GET_APIC_ID(apic_read(APIC_ID)); /* * Add it to the IO-APIC irq-routing table: @@ -1524,7 +1522,7 @@ entry1.dest_mode = 0; /* physical delivery */ entry1.mask = 0; /* unmask IRQ now */ - entry1.dest.physical.physical_dest = hard_smp_processor_id(); + entry1.dest = hard_smp_processor_id(); entry1.delivery_mode = dest_ExtINT; entry1.polarity = entry0.polarity; entry1.trigger = 0; @@ -2092,7 +2090,7 @@ entry.delivery_mode = INT_DELIVERY_MODE; entry.dest_mode = INT_DEST_MODE; - entry.dest.logical.logical_dest = cpu_mask_to_apicid(mask); + entry.dest = cpu_mask_to_apicid(mask); entry.trigger = triggering; entry.polarity = polarity; entry.mask = 1; /* Disabled (masked) */ diff -ru linux-2.6.19.2-orig/include/asm-x86_64/io_apic.h linux-2.6.19.2/include/asm-x86_64/io_apic.h --- linux-2.6.19.2-orig/include/asm-x86_64/io_apic.h 2007-03-18 12:30:07.000000000 -0400 +++ linux-2.6.19.2/include/asm-x86_64/io_apic.h 2007-03-18 12:58:37.000000000 -0400 @@ -72,31 +72,21 @@ }; struct IO_APIC_route_entry { - __u32 vector : 8, - delivery_mode : 3, /* 000: FIXED - * 001: lowest prio - * 111: ExtINT - */ - dest_mode : 1, /* 0: physical, 1: logical */ - delivery_status : 1, - polarity : 1, - irr : 1, - trigger : 1, /* 0: edge, 1: level */ - mask : 1, /* 0: enabled, 1: disabled */ - __reserved_2 : 15; - - union { struct { __u32 - __reserved_1 : 24, - physical_dest : 4, - __reserved_2 : 4; - } physical; - - struct { __u32 - __reserved_1 : 24, - logical_dest : 8; - } logical; - } dest; + __u32 vector : 8, + delivery_mode : 3, /* 000: FIXED + * 001: lowest prio + * 111: ExtINT + */ + dest_mode : 1, /* 0: physical, 1: logical */ + delivery_status : 1, + polarity : 1, + irr : 1, + trigger : 1, /* 0: edge, 1: level */ + mask : 1, /* 0: enabled, 1: disabled */ + __reserved_2 : 15; + __u32 __reserved_3 : 24, + dest : 8; } __attribute__ ((packed)); /* - 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/