Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267446AbUIJOxl (ORCPT ); Fri, 10 Sep 2004 10:53:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267447AbUIJOxl (ORCPT ); Fri, 10 Sep 2004 10:53:41 -0400 Received: from fw-us-hou19.bmc.com ([198.207.223.240]:46060 "EHLO mangrove.bmc.com") by vger.kernel.org with ESMTP id S267446AbUIJOxe (ORCPT ); Fri, 10 Sep 2004 10:53:34 -0400 Message-ID: <1094828013.19339.1000.camel@levlinux.boston.bmc.com> From: "Makhlis, Lev" To: Andrew Morton Cc: "Makhlis, Lev" , linux-kernel@vger.kernel.org Subject: [PATCH 2.6.9-rc1-mm4] fix BUG in do_task_stat() Date: Fri, 10 Sep 2004 09:53:25 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2088 Lines: 65 > > kernel BUG in next_thread at kernel/exit.c:852! > cpu 0x2: Vector: 700 (Program Check) at [c00000027bcf3770] > pc: c000000000058454: .next_thread+0x14/0x48 > lr: c0000000000f1a84: .do_task_stat+0x238/0x53c > I've been able to reproduce this. This patch makes sure next_thread() is only called while holding ->sighand->siglock. Ran it overnight with a load, and no problems so far. Signed-off-by: Lev Makhlis diff -pruN linux-2.6.9-rc1-mm4/fs/proc/array.c linux/fs/proc/array.c --- linux-2.6.9-rc1-mm4/fs/proc/array.c 2004-09-09 18:06:19.265831912 -0400 +++ linux/fs/proc/array.c 2004-09-09 18:01:34.221165288 -0400 @@ -336,6 +336,16 @@ static int do_task_stat(struct task_stru spin_lock_irq(&task->sighand->siglock); num_threads = atomic_read(&task->signal->count); collect_sigign_sigcatch(task, &sigign, &sigcatch); + if (whole) { + t = task; + do { + min_flt += t->min_flt; + maj_flt += t->maj_flt; + utime += t->utime; + stime += t->stime; + t = next_thread(t); + } while (t != task); + } spin_unlock_irq(&task->sighand->siglock); } if (task->signal) { @@ -350,22 +360,12 @@ static int do_task_stat(struct task_stru cutime = task->signal->cutime; cstime = task->signal->cstime; if (whole) { - min_flt = task->signal->min_flt; - maj_flt = task->signal->maj_flt; - utime = task->signal->utime; - stime = task->signal->stime; + min_flt += task->signal->min_flt; + maj_flt += task->signal->maj_flt; + utime += task->signal->utime; + stime += task->signal->stime; } } - if (whole) { - t = task; - do { - min_flt += t->min_flt; - maj_flt += t->maj_flt; - utime += t->utime; - stime += t->stime; - t = next_thread(t); - } while (t != task); - } ppid = task->pid ? task->real_parent->pid : 0; read_unlock(&tasklist_lock); - 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/