Re: Dirtiable inode bdi default != sb bdi btrfs

[Andrew Morton <akpm@linux-foundation.org>]

(Cc stable@kernel.org)

On Wed, 22 Sep 2010 21:54:30 -0300
Cesar Eduardo Barros <cesarb@cesarb.net> wrote:

> This started appearing for me on v2.6.36-rc5-49-gc79bd89; it did not 
> happen on v2.6.36-rc5-33-g1ce1e41, probably because it does not have 
> commit 692ebd17c2905313fff3c504c249c6a0faad16ec which introduces the 
> warning.
> 
> [...]
> device fsid 44d595920ddedfa-3ece6b56e80f689e devid 1 transid 22342 
> /dev/mapper/vg_cesarbinspiro-lv_home
> SELinux: initialized (dev dm-3, type btrfs), uses xattr
> ------------[ cut here ]------------
> WARNING: at fs/fs-writeback.c:87 inode_to_bdi+0x62/0x6d()
> Hardware name: Inspiron N4010
> Dirtiable inode bdi default != sb bdi btrfs
> Modules linked in: ipv6 kvm_intel kvm uinput arc4 ecb 
> snd_hda_codec_intelhdmi snd_hda_codec_realtek iwlagn snd_hda_intel 
> iwlcore snd_hda_codec uvcvideo snd_hwdep mac80211 videodev snd_seq 
> snd_seq_device v4l1_compat snd_pcm atl1c v4l2_compat_ioctl32 btusb 
> cfg80211 snd_timer i2c_i801 bluetooth iTCO_wdt dell_wmi dell_laptop snd 
> pcspkr wmi dcdbas shpchp iTCO_vendor_support soundcore snd_page_alloc 
> rfkill joydev microcode btrfs zlib_deflate libcrc32c cryptd aes_x86_64 
> aes_generic xts gf128mul dm_crypt usb_storage i915 drm_kms_helper drm 
> i2c_algo_bit i2c_core video output [last unloaded: scsi_wait_scan]
> Pid: 1073, comm: find Not tainted 2.6.36-rc5+ #8
> Call Trace:
>   [<ffffffff8104d0e4>] warn_slowpath_common+0x85/0x9d
>   [<ffffffff8104d19f>] warn_slowpath_fmt+0x46/0x48
>   [<ffffffff811308b7>] inode_to_bdi+0x62/0x6d
>   [<ffffffff81131b48>] __mark_inode_dirty+0xd0/0x177
>   [<ffffffff81127168>] touch_atime+0x107/0x12a
>   [<ffffffff81122384>] ? filldir+0x0/0xd0
>   [<ffffffff8112259b>] vfs_readdir+0x8d/0xb4
>   [<ffffffff8112270b>] sys_getdents+0x81/0xd1
>   [<ffffffff81009c72>] system_call_fastpath+0x16/0x1b

Thanks.  692ebd17c2905313fff3c504c249c6a0faad16ec had a cc:stable in
the changelog.  I'd suggest it not be merged into -stable until this
regression is sorted out!

>
> ...
> 
> These are only the first two; they keep happening, with several 
> different processes (it is not only find), but always btrfs (I have / 
> and /home on btrfs and /boot on ext4). In case it makes any difference, 
> /dev seems to be on devtmpfs, and everything uses relatime.
> 
> There is also the following one which is not on vfs_readdir:
> 
> ------------[ cut here ]------------
> WARNING: at fs/fs-writeback.c:87 inode_to_bdi+0x62/0x6d()
> Hardware name: Inspiron N4010
> Dirtiable inode bdi default != sb bdi btrfs
> Modules linked in: ipv6 kvm_intel kvm uinput arc4 ecb 
> snd_hda_codec_intelhdmi snd_hda_codec_realtek iwlagn snd_hda_intel 
> iwlcore snd_hda_codec uvcvideo snd_hwdep mac80211 videodev snd_seq 
> snd_seq_device v4l1_compat snd_pcm atl1c v4l2_compat_ioctl32 btusb 
> cfg80211 snd_timer i2c_i801 bluetooth iTCO_wdt dell_wmi dell_laptop snd 
> pcspkr wmi dcdbas shpchp iTCO_vendor_support soundcore snd_page_alloc 
> rfkill joydev microcode btrfs zlib_deflate libcrc32c cryptd aes_x86_64 
> aes_generic xts gf128mul dm_crypt usb_storage i915 drm_kms_helper drm 
> i2c_algo_bit i2c_core video output [last unloaded: scsi_wait_scan]
> Pid: 1104, comm: mkdir Tainted: G        W   2.6.36-rc5+ #8
> Call Trace:
>   [<ffffffff8104d0e4>] warn_slowpath_common+0x85/0x9d
>   [<ffffffff8104d19f>] warn_slowpath_fmt+0x46/0x48
>   [<ffffffff811308b7>] inode_to_bdi+0x62/0x6d
>   [<ffffffff81131b48>] __mark_inode_dirty+0xd0/0x177
>   [<ffffffffa01408c6>] btrfs_setattr+0x210/0x23a [btrfs]
>   [<ffffffff8112865e>] notify_change+0x1a2/0x29d
>   [<ffffffff81113794>] sys_fchmod+0xac/0xfd
>   [<ffffffff811188e2>] ? sys_newfstat+0x2e/0x39
>   [<ffffffff81009c72>] system_call_fastpath+0x16/0x1b