Greetings, 0day kernel testing robot got the below dmesg and the first bad commit is https://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-next.git kill-btree-inode commit ab7724daa909923e8dd5baca685ccc1dfa3fa413 Author: Josef Bacik <jbacik(a)fb.com&gt; AuthorDate: Wed Aug 17 16:56:35 2016 -0400 Commit: Josef Bacik <jbacik(a)fb.com&gt; CommitDate: Mon Aug 22 09:18:45 2016 -0400 writeback: introduce super_operations->write_metadata Now that we have metadata counters in the VM, we need to provide a way to kick writeback on dirty metadata. Introduce super_operations->write_metadata. This allows file systems to deal with writing back any dirty metadata we need based on the writeback needs of the system. Since there is no inode to key off of we need a list in the bdi for dirty super blocks to be added. From there we can find any dirty sb's on the bdi we are currently doing writeback on and call into their ->write_metadata callback. Signed-off-by: Josef Bacik <jbacik(a)fb.com&gt; +---------------------------------------+------------+------------+------------+ | | ac04c3c6a3 | ab7724daa9 | bfcea1e771 | +---------------------------------------+------------+------------+------------+ | boot_successes | 83 | 2 | 6 | | boot_failures | 0 | 31 | 21 | | BUG:spinlock_bad_magic_on_CPU | 0 | 31 | 21 | | message:BUG:spinlock_bad_magic_on_CPU | 0 | 0.0 | 0.0 | | pattern:BUG:spinlock_bad_magic_on_CPU | 0 | 0 | 0 | +---------------------------------------+------------+------------+------------+ Kernel tests: Boot OK! Kernel tests: Boot OK! udevd[343]: failed to execute '/sbin/modprobe' '/sbin/modprobe -bv acpi:PNP0A06:': No such file or directory [ 5.957606] BUG: spinlock bad magic on CPU#0, umount/354 [ 5.958745] lock: 0xffffffff81e57d28, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0 [ 5.960425] CPU: 0 PID: 354 Comm: umount Not tainted 4.7.0-11586-gab7724d #2 [ 5.961893] 0000000000000000 ffff88001f35fcd8 ffffffff8134902b ffff88001f35fcf8 [ 5.963530] ffffffff81108bd2 ffffffff81e57d28 ffffffff81cc22e0 ffff88001f35fd18 [ 5.966585] ffffffff81108c4e ffffffff81e57d28 0000000000000001 ffff88001f35fd48 [ 5.968219] Call Trace: [ 5.968757] [<ffffffff8134902b>] dump_stack+0x19/0x1b [ 5.969816] [<ffffffff81108bd2>] spin_dump+0x8e/0xcc [ 5.970853] [<ffffffff81108c4e>] spin_bug+0x3e/0x43 [ 5.971875] [<ffffffff81108fef>] do_raw_spin_lock+0x1cb/0x1ec [ 5.973095] [<ffffffff818654a4>] _raw_spin_lock+0x14/0x16 [ 5.974224] [<ffffffff8122b8a7>] deactivate_locked_super+0x93/0xd9 [ 5.975512] [<ffffffff8122c360>] deactivate_super+0xf0/0x100 [ 5.978605] [<ffffffff8125bfbd>] cleanup_mnt+0xad/0xe0 [ 5.979686] [<ffffffff8125d867>] __cleanup_mnt+0x12/0x14 [ 5.980808] [<ffffffff810e8fa6>] task_work_run+0xbf/0x115 [ 5.981930] [<ffffffff81002055>] exit_to_usermode_loop+0x1bc/0x1e3 [ 5.983229] [<ffffffff8125c20c>] ? mntput_no_expire+0x21c/0x2b5 [ 5.984451] [<ffffffff8100232e>] syscall_return_slowpath+0xb6/0xd6 [ 5.985734] [<ffffffff81865690>] entry_SYSCALL_64_fastpath+0xb6/0xb8 Elapsed time: 20 git bisect start bfcea1e771f165038364750f04524e9a8f44da51 3eab887a55424fc2c27553b7bfe32330df83f7b8 -- git bisect bad b37d27e813bead1516a24524e8cd1f186a5512dd # 04:11 0- 1 Merge 'arm-integrator/apq8060-dragonboard-ethernet' into devel-spot-201609010131 git bisect bad 2a9a76818d4f84c59a8911d85b7198e9012f9185 # 04:16 0- 3 Merge 'char-misc/char-misc-testing' into devel-spot-201609010131 git bisect bad b598532f8700e90bc8d35c0e0d5f02775bbec39e # 04:22 0- 15 Merge 'cryptodev/master' into devel-spot-201609010131 git bisect bad ac86ab4d064cb69d471ccc6e8d40542f578264d3 # 04:29 0- 20 Merge 'slave-dma/topic/err_reporting' into devel-spot-201609010131 git bisect good d94ba5efdad7b30cea41b6d83091576a56df8588 # 04:40 27+ 0 Merge 'iio/testing' into devel-spot-201609010131 git bisect good b9d75b82497aceb03d11b54569955c1725714d02 # 04:45 25+ 0 Merge 'abelloni/rtc-next' into devel-spot-201609010131 git bisect bad d46d323639c89f5faec5fe487a315a086a98b853 # 04:53 0- 5 Merge 'josef-btrfs/kill-btree-inode' into devel-spot-201609010131 git bisect good ac04c3c6a3ed07c0a3a0b0d89337c08ccb3e9886 # 05:00 27+ 0 writeback: allow for dirty metadata accounting git bisect bad 3fef71185041c3f81e1c10159add01f3312a51a7 # 05:05 0- 3 Btrfs: fix em leak in find_first_block_group git bisect bad ab7724daa909923e8dd5baca685ccc1dfa3fa413 # 05:07 0- 9 writeback: introduce super_operations->write_metadata # first bad commit: [ab7724daa909923e8dd5baca685ccc1dfa3fa413] writeback: introduce super_operations->write_metadata git bisect good ac04c3c6a3ed07c0a3a0b0d89337c08ccb3e9886 # 05:11 79+ 0 writeback: allow for dirty metadata accounting # extra tests with CONFIG_DEBUG_INFO_REDUCED git bisect bad ab7724daa909923e8dd5baca685ccc1dfa3fa413 # 05:20 0- 3 writeback: introduce super_operations->write_metadata # extra tests on HEAD of linux-devel/devel-spot-201609010131 git bisect bad bfcea1e771f165038364750f04524e9a8f44da51 # 05:20 0- 21 0day head guard for 'devel-spot-201609010131' # extra tests on tree/branch josef-btrfs/kill-btree-inode git bisect bad 47763aed48f76b160b3ad555f9202c9c69bc28ec # 05:26 0- 6 Bpf: allow access into map value arrays # extra tests with first bad commit reverted git bisect good 4673c1393e7544aead75b0e9573b64486f60cc77 # 05:36 82+ 0 Revert "writeback: introduce super_operations->write_metadata" # extra tests on tree/branch linus/master git bisect good 071e31e254e0e0c438eecba3dba1d6e2d0da36c2 # 05:43 82+ 0 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 # extra tests on tree/branch linux-next/master git bisect good 0f98f121e1670eaa2a2fbb675e07d6ba7f0e146f # 05:49 80+ 3 Add linux-next specific files for 20160825 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/lkp Intel Corporation