On Thu, 27 Dec 2012 14:29:07 +0800, Zheng Liu <gnehzuil.liu@xxxxxxxxx> wrote: > On Thu, Dec 27, 2012 at 03:27:04AM +0300, Alexander Beregalov wrote: > > Hello > > > > Let me know if you need more info > > > > EXT4-fs (sda2): INFO: recovery required on readonly filesystem > > EXT4-fs (sda2): write access will be enabled during recovery > > EXT4-fs (sda2): orphan cleanup on readonly fs > > EXT4-fs (sda2): ext4_orphan_cleanup: truncating inode 841849 to 0 bytes > > ------------[ cut here ]------------ > > WARNING: at fs/ext4/page-io.c:232 ext4_flush_unwritten_io+0x6b/0x80() > > Hardware name: P35-DS3 > > Modules linked in: > > Pid: 1, comm: swapper/0 Not tainted 3.8.0-rc1-00004-g637704c #1 > > Call Trace: > > [<ffffffff81038f5a>] warn_slowpath_common+0x7a/0xb0 > > [<ffffffff81038fa5>] warn_slowpath_null+0x15/0x20 > > [<ffffffff81163b8b>] ext4_flush_unwritten_io+0x6b/0x80 > > [<ffffffff8117ac5c>] ext4_ext_truncate+0x2c/0x1f0 > > [<ffffffff8116c6d0>] ? ext4_msg+0x50/0x60 > > [<ffffffff8115e050>] ext4_truncate+0x70/0xb0 > > [<ffffffff8117190b>] ext4_fill_super+0x2bab/0x2ce0 > > [<ffffffff810ef02a>] mount_bdev+0x1aa/0x1f0 > > [<ffffffff8102aec9>] ? default_spin_lock_flags+0x9/0x10 > > [<ffffffff8116ed60>] ? ext4_calculate_overhead+0x3a0/0x3a0 > > [<ffffffff8116a870>] ext4_mount+0x10/0x20 > > [<ffffffff810ef96b>] mount_fs+0x1b/0xd0 > > [<ffffffff81108fc1>] vfs_kern_mount+0x71/0x110 > > [<ffffffff8110b096>] do_mount+0x386/0x980 > > [<ffffffff810b7f43>] ? strndup_user+0x53/0x70 > > [<ffffffff8110b71b>] sys_mount+0x8b/0xe0 > > [<ffffffff816afcc8>] mount_block_root+0xfe/0x298 > > [<ffffffff816afeb8>] mount_root+0x56/0x5a > > [<ffffffff816afff0>] prepare_namespace+0x134/0x16d > > [<ffffffff8147c9c6>] kernel_init+0x196/0x2a0 > > [<ffffffff816af539>] ? loglevel+0x31/0x31 > > [<ffffffff8147c830>] ? rest_init+0x80/0x80 > > [<ffffffff81482a7c>] ret_from_fork+0x7c/0xb0 > > [<ffffffff8147c830>] ? rest_init+0x80/0x80 > > ---[ end trace 425942f4f0ed8d07 ]--- > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 835709 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 835629 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 682715 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 832545 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 677529 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 838885 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 676342 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 832311 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 683216 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 828057 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 847476 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 834769 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 846534 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 842096 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 833886 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 688996 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 1085523 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 524364 > > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 12686 > > EXT4-fs (sda2): 19 orphan inodes deleted > > EXT4-fs (sda2): 1 truncate cleaned up > > EXT4-fs (sda2): recovery complete > > EXT4-fs (sda2): mounted filesystem with ordered data mode. Opts: (null) > > Hi Alexander, > > This warning is from ext4_flush_unwritten_io() because we need to take > i_mutex lock before calling this function. Ohterwise we will trigger a > WARN_ON_ONCE(). But, unfortunately, we don't take this lock in > ext4_orphan_cleanup(). So that is why we will get this warning when > cleaning up orphan list. Could you please test this patch? > > Thanks, > - Zheng > > Subject: [PATCH] ext4: fixup a warning from ext4_flush_unwritten_io() in orphan list cleanup > > From: Zheng Liu <wenqing.lz@xxxxxxxxxx> > > When ext4 tries to clean up orphan list, we will get the following warning from > ext4_flush_unwritten_io() because i_mutex lock doesn't be taken. > > EXT4-fs (sda2): INFO: recovery required on readonly filesystem > EXT4-fs (sda2): write access will be enabled during recovery > EXT4-fs (sda2): orphan cleanup on readonly fs > EXT4-fs (sda2): ext4_orphan_cleanup: truncating inode 841849 to 0 bytes > ------------[ cut here ]------------ > WARNING: at fs/ext4/page-io.c:232 ext4_flush_unwritten_io+0x6b/0x80() > Hardware name: P35-DS3 > Modules linked in: > Pid: 1, comm: swapper/0 Not tainted 3.8.0-rc1-00004-g637704c #1 > Call Trace: > [<ffffffff81038f5a>] warn_slowpath_common+0x7a/0xb0 > [<ffffffff81038fa5>] warn_slowpath_null+0x15/0x20 > [<ffffffff81163b8b>] ext4_flush_unwritten_io+0x6b/0x80 > [<ffffffff8117ac5c>] ext4_ext_truncate+0x2c/0x1f0 > [<ffffffff8116c6d0>] ? ext4_msg+0x50/0x60 > [<ffffffff8115e050>] ext4_truncate+0x70/0xb0 > [<ffffffff8117190b>] ext4_fill_super+0x2bab/0x2ce0 > [<ffffffff810ef02a>] mount_bdev+0x1aa/0x1f0 > [<ffffffff8102aec9>] ? default_spin_lock_flags+0x9/0x10 > [<ffffffff8116ed60>] ? ext4_calculate_overhead+0x3a0/0x3a0 > [<ffffffff8116a870>] ext4_mount+0x10/0x20 > [<ffffffff810ef96b>] mount_fs+0x1b/0xd0 > [<ffffffff81108fc1>] vfs_kern_mount+0x71/0x110 > [<ffffffff8110b096>] do_mount+0x386/0x980 > [<ffffffff810b7f43>] ? strndup_user+0x53/0x70 > [<ffffffff8110b71b>] sys_mount+0x8b/0xe0 > [<ffffffff816afcc8>] mount_block_root+0xfe/0x298 > [<ffffffff816afeb8>] mount_root+0x56/0x5a > [<ffffffff816afff0>] prepare_namespace+0x134/0x16d > [<ffffffff8147c9c6>] kernel_init+0x196/0x2a0 > [<ffffffff816af539>] ? loglevel+0x31/0x31 > [<ffffffff8147c830>] ? rest_init+0x80/0x80 > [<ffffffff81482a7c>] ret_from_fork+0x7c/0xb0 > [<ffffffff8147c830>] ? rest_init+0x80/0x80 > ---[ end trace 425942f4f0ed8d07 ]--- > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 835709 > EXT4-fs (sda2): ext4_orphan_cleanup: deleting unreferenced inode 835629 > > Now we try to take i_mutex lock before orphan list cleanup, although we don't > need to take it in ext4_orphan_cleanup() because no one write this inode. > WARN_ON_ONCE doesn't be removed because this warning could help us to avoid some > ciritcal errors. You can add Ack-by: Dmitry Monakhov <dmonakhov@xxxxxxxxxx> In fact this is my fault that we still not have autotest for that. I'm think of add crash-test to xfstests which should trigger journal abort and forced umount. Later test should mount FS which trigger journal_replay and orphan_cleanup. > > CC: Dmitry Monakhov <dmonakhov@xxxxxxxxxx> > Reported-by: Alexander Beregalov <a.beregalov@xxxxxxxxx> > Signed-off-by: Zheng Liu <wenqing.lz@xxxxxxxxxx> > --- > fs/ext4/super.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/fs/ext4/super.c b/fs/ext4/super.c > index 3cdb0a2..188d6f1 100644 > --- a/fs/ext4/super.c > +++ b/fs/ext4/super.c > @@ -2212,7 +2212,18 @@ static void ext4_orphan_cleanup(struct super_block *sb, > __func__, inode->i_ino, inode->i_size); > jbd_debug(2, "truncating inode %lu to %lld bytes\n", > inode->i_ino, inode->i_size); > + /* > + * Actually we don't need to take i_mutex lock > + * because in orphan list cleanup no one can write > + * this inode. We take it here because in calling > + * ext4_flush_unwritten_io() this lock needs to be > + * taken, and we don't want to remove this > + * WARN_ON_ONCE(). It is useful for us to avoid some > + * critical errors. > + */ > + mutex_lock(&inode->i_mutex); > ext4_truncate(inode); > + mutex_unlock(&inode->i_mutex); > nr_truncates++; > } else { > ext4_msg(sb, KERN_DEBUG, > -- > 1.7.12.rc2.18.g61b472e > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html