From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753612AbZIKAa3 (ORCPT ); Thu, 10 Sep 2009 20:30:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753301AbZIKA3L (ORCPT ); Thu, 10 Sep 2009 20:29:11 -0400 Received: from kroah.org ([198.145.64.141]:38090 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751679AbZIKA3H (ORCPT ); Thu, 10 Sep 2009 20:29:07 -0400 X-Mailbox-Line: From gregkh@mini.kroah.org Thu Sep 10 17:24:11 2009 Message-Id: <20090911002410.971758034@mini.kroah.org> User-Agent: quilt/0.48-1 Date: Thu, 10 Sep 2009 17:22:59 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Ryusuke Konishi Subject: [patch 13/22] nilfs2: fix preempt count underflow in nilfs_btnode_prepare_change_key References: <20090911002246.666327880@mini.kroah.org> Content-Disposition: inline; filename=nilfs2-fix-preempt-count-underflow-in-nilfs_btnode_prepare_change_key.patch In-Reply-To: <20090911002616.GA12087@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.30-stable review patch. If anyone has any objections, please let us know. ------------------ From: Ryusuke Konishi commit b1f1b8ce0a1d71cbc72f7540134d52b79bd8f5ac upstream. This will fix the following preempt count underflow reported from users with the title "[NILFS users] segctord problem" (Message-ID: <949415.6494.qm@web58808.mail.re1.yahoo.com> and Message-ID: ): WARNING: at kernel/sched.c:4890 sub_preempt_count+0x95/0xa0() Hardware name: HP Compaq 6530b (KR980UT#ABC) Modules linked in: bridge stp llc bnep rfcomm l2cap xfs exportfs nilfs2 cowloop loop vboxnetadp vboxnetflt vboxdrv btusb bluetooth uvcvideo videodev v4l1_compat v4l2_compat_ioctl32 arc4 snd_hda_codec_analog ecb iwlagn iwlcore rfkill lib80211 mac80211 snd_hda_intel snd_hda_codec ehci_hcd uhci_hcd usbcore snd_hwdep snd_pcm tg3 cfg80211 psmouse snd_timer joydev libphy ohci1394 snd_page_alloc hp_accel lis3lv02d ieee1394 led_class i915 drm i2c_algo_bit video backlight output i2c_core dm_crypt dm_mod Pid: 4197, comm: segctord Not tainted 2.6.30-gentoo-r4-64 #7 Call Trace: [] ? sub_preempt_count+0x95/0xa0 [] warn_slowpath_common+0x78/0xd0 [] warn_slowpath_null+0xf/0x20 [] sub_preempt_count+0x95/0xa0 [] nilfs_btnode_prepare_change_key+0x11b/0x190 [nilfs2] [] nilfs_btree_assign_p+0x19d/0x1e0 [nilfs2] [] nilfs_btree_assign+0xbd/0x130 [nilfs2] [] nilfs_bmap_assign+0x47/0x70 [nilfs2] [] nilfs_segctor_do_construct+0x956/0x20f0 [nilfs2] [] ? _spin_unlock_irqrestore+0x12/0x40 [] ? __up_write+0xe0/0x150 [] ? up_write+0x9/0x10 [] ? nilfs_bmap_test_and_clear_dirty+0x43/0x60 [nilfs2] [] ? nilfs_mdt_fetch_dirty+0x27/0x60 [nilfs2] [] nilfs_segctor_construct+0x8c/0xd0 [nilfs2] [] nilfs_segctor_thread+0x15c/0x3a0 [nilfs2] [] ? nilfs_construction_timeout+0x0/0x10 [nilfs2] [] ? add_timer+0x13/0x20 [] ? __wake_up_common+0x5a/0x90 [] ? autoremove_wake_function+0x0/0x40 [] ? nilfs_segctor_thread+0x0/0x3a0 [nilfs2] [] ? nilfs_segctor_thread+0x0/0x3a0 [nilfs2] [] kthread+0x56/0x90 [] child_rip+0xa/0x20 [] ? kthread+0x0/0x90 [] ? child_rip+0x0/0x20 This problem was caused due to a missing radix_tree_preload() call in the retry path of nilfs_btnode_prepare_change_key() function. Reported-by: Eric A Reported-by: Jerome Poulin Signed-off-by: Ryusuke Konishi Tested-by: Jerome Poulin Signed-off-by: Greg Kroah-Hartman --- fs/nilfs2/btnode.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/nilfs2/btnode.c +++ b/fs/nilfs2/btnode.c @@ -206,6 +206,7 @@ int nilfs_btnode_prepare_change_key(stru * We cannot call radix_tree_preload for the kernels older * than 2.6.23, because it is not exported for modules. */ +retry: err = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM); if (err) goto failed_unlock; @@ -216,7 +217,6 @@ int nilfs_btnode_prepare_change_key(stru (unsigned long long)oldkey, (unsigned long long)newkey); -retry: spin_lock_irq(&btnc->tree_lock); err = radix_tree_insert(&btnc->page_tree, newkey, obh->b_page); spin_unlock_irq(&btnc->tree_lock);