Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759537AbZFXVg1 (ORCPT ); Wed, 24 Jun 2009 17:36:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751721AbZFXVgU (ORCPT ); Wed, 24 Jun 2009 17:36:20 -0400 Received: from kroah.org ([198.145.64.141]:54818 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751971AbZFXVgT (ORCPT ); Wed, 24 Jun 2009 17:36:19 -0400 Date: Wed, 24 Jun 2009 14:32:11 -0700 From: Greg KH To: x86@kernel.org Cc: "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , Kurt Garloff , linux-kernel@vger.kernel.org Subject: [PATCH] x86: sysctl to allow panic on IOCK NMI error Message-ID: <20090624213211.GA11291@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3602 Lines: 111 From: Kurt Garloff This patch introduces a sysctl /proc/sys/kernel/panic_on_io_nmi, which defaults to 0 (off). When enabled, the kernel panics when the kernel receives an NMI caused by an IO error. The IO error triggered NMI indicates a serious system condition, which could result in IO data corruption. Rather than contiuing, panicing and dumping might be a better choice, so one can figure out what's causing the IO error. This could be especially important to companies running IO intensive applications where corruption must be avoided, e.g. a banks databases. Signed-off-by: Kurt Garloff Signed-off-by: Roberto Angelino Signed-off-by: Greg Kroah-Hartman --- I don't know why this wasn't sent to you before now, sorry about that. SuSE has been shipping it for a while, it was done at the request of a large database vendor, for their users. Can you queue it up for .32? - gregkh arch/x86/kernel/dumpstack.c | 1 + arch/x86/kernel/traps.c | 3 +++ include/linux/kernel.h | 1 + include/linux/sysctl.h | 1 + kernel/sysctl.c | 8 ++++++++ kernel/sysctl_check.c | 1 + 6 files changed, 15 insertions(+) --- a/arch/x86/kernel/dumpstack.c +++ b/arch/x86/kernel/dumpstack.c @@ -22,6 +22,7 @@ #include "dumpstack.h" int panic_on_unrecovered_nmi; +int panic_on_io_nmi; unsigned int code_bytes = 64; int kstack_depth_to_print = 3 * STACKSLOTS_PER_LINE; static int die_counter; --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -346,6 +346,9 @@ io_check_error(unsigned char reason, str printk(KERN_EMERG "NMI: IOCK error (debug interrupt?)\n"); show_registers(regs); + if (panic_on_io_nmi) + panic("NMI IOCK error: Not continuing"); + /* Re-enable the IOCK line, wait for a few seconds */ reason = (reason & 0xf) | 8; outb(reason, 0x61); --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -303,6 +303,7 @@ extern int oops_in_progress; /* If set, extern int panic_timeout; extern int panic_on_oops; extern int panic_on_unrecovered_nmi; +extern int panic_on_io_nmi; extern const char *print_tainted(void); extern void add_taint(unsigned flag); extern int test_taint(unsigned flag); --- a/include/linux/sysctl.h +++ b/include/linux/sysctl.h @@ -163,6 +163,7 @@ enum KERN_MAX_LOCK_DEPTH=74, KERN_NMI_WATCHDOG=75, /* int: enable/disable nmi watchdog */ KERN_PANIC_ON_NMI=76, /* int: whether we will panic on an unrecovered */ + KERN_PANIC_ON_IO_NMI=77, /* int: whether we will panic on an io NMI */ }; --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -744,6 +744,14 @@ static struct ctl_table kern_table[] = { .proc_handler = &proc_dointvec, }, { + .ctl_name = KERN_PANIC_ON_IO_NMI, + .procname = "panic_on_io_nmi", + .data = &panic_on_io_nmi, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { .ctl_name = KERN_BOOTLOADER_TYPE, .procname = "bootloader_type", .data = &bootloader_type, --- a/kernel/sysctl_check.c +++ b/kernel/sysctl_check.c @@ -104,6 +104,7 @@ static const struct trans_ctl_table tran { KERN_MAX_LOCK_DEPTH, "max_lock_depth" }, { KERN_NMI_WATCHDOG, "nmi_watchdog" }, { KERN_PANIC_ON_NMI, "panic_on_unrecovered_nmi" }, + { KERN_PANIC_ON_IO_NMI, "panic_on_io_nmi" }, {} }; -- 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/