Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751442Ab3CAGAP (ORCPT ); Fri, 1 Mar 2013 01:00:15 -0500 Received: from mail-da0-f50.google.com ([209.85.210.50]:59672 "EHLO mail-da0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750884Ab3CAGAN (ORCPT ); Fri, 1 Mar 2013 01:00:13 -0500 From: Yong Zhang To: linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org Cc: Thomas Gleixner , Steven Rostedt Subject: [V2 PATCH -rt] futex: fix unbalanced spin_lock/spin_unlock() in exit_pi_state_list() Date: Fri, 1 Mar 2013 14:00:03 +0800 Message-Id: <1362117603-9480-1-git-send-email-yong.zhang0@gmail.com> X-Mailer: git-send-email 1.7.9.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2024 Lines: 58 From: Yong Zhang Otherwise, below warning is shown somtimes when running some test: WARNING: at kernel/sched/core.c:3423 migrate_disable+0xbf/0xd0() Hardware name: OptiPlex 755 Modules linked in: floppy parport parport_pc minix Pid: 1800, comm: tst-robustpi8 Tainted: G W 3.4.28-rt40 #1 Call Trace: [] warn_slowpath_common+0x7f/0xc0 [] warn_slowpath_null+0x1a/0x20 [] migrate_disable+0xbf/0xd0 [] exit_pi_state_list+0xa5/0x170 [] mm_release+0x12f/0x170 [] exit_mm+0x26/0x140 [] ? acct_collect+0x186/0x1c0 [] do_exit+0x146/0x930 [] ? get_parent_ip+0x11/0x50 [] do_group_exit+0x4d/0xc0 [] get_signal_to_deliver+0x23f/0x6a0 [] do_signal+0x65/0x5e0 [] ? group_send_sig_info+0x76/0x80 [] do_notify_resume+0x98/0xd0 [] int_signal+0x12/0x17 ---[ end trace 0000000000000004 ]--- The reason is that spin_lock() is taken in atomic context, but spin_unlock() is not. Signed-off-by: Yong Zhang Cc: Thomas Gleixner Cc: Steven Rostedt --- kernel/futex.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/futex.c b/kernel/futex.c index 9e26e87..daada3d 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -568,7 +568,9 @@ void exit_pi_state_list(struct task_struct *curr) * task still owns the PI-state: */ if (head->next != next) { + raw_spin_unlock_irq(&curr->pi_lock); spin_unlock(&hb->lock); + raw_spin_lock_irq(&curr->pi_lock); continue; } -- 1.7.9.5 -- 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/