Hi Jan, Here is another warning for the fs freeze series. tree: git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git fsfreeze head: 7aff72a61f45337d83ab2b7fb16d7b542db16ad8 commit: bc875c078f72993e6c44925cdedef5a304ca7429 [37/51] fs: Improve filesystem freezing handling The warning shows up reliably since commit bc875c0. The 2nd commit 51205f9 triggers the same warning as the previous email. 36: b 4a55c10 GOOD 37: B bc875c0 kvm-xgwo [ 995.982449] BUG: sleeping function called from invalid context 38: B 51205f9 kvm-stoakley [ 7.209014] [ INFO: possible circular locking dependency detected ] [mnt_want_write vfs_readdir __lock_acquire lock_acquire mutex_lock_nested do_last path_openat do_filp_open do_sys_open sys_open system_call_fastpath validate_chain __lock_acquire lock_acquire __sb_start_write mnt_want_write touch_atime vfs_readdir sys_getdents system_call_fastpath vfs_readdir print_circular_bug validate_chain __lock_acquire lock_acquire __sb_start_write mnt_want_write touch_atime vfs_readdir sys_getdents system_call_fastpath] 39: B 5bc2ab9 kvm-stoakley [ 737.432929] BUG: sleeping function called from invalid context 40: B f7df8ce kvm-waimea [ 178.809146] BUG: sleeping function called from invalid context 41: B e681724 kvm-waimea [ 174.246222] BUG: sleeping function called from invalid context 42: B 3b6be95 kvm-waimea [ 227.717663] BUG: sleeping function called from invalid context 43: B 770324a kvm-slim [ 978.365294] BUG: sleeping function called from invalid context 44: B 412c18b kvm-xgwo [ 941.146711] BUG: sleeping function called from invalid context 45: B bc20d4d kvm-waimea [ 158.598232] BUG: sleeping function called from invalid context 46: B 34daaf5 kvm-waimea [ 162.483310] BUG: sleeping function called from invalid context 47: B 1e8b839 kvm-waimea [ 197.966631] BUG: sleeping function called from invalid context 48: B 3720c99 kvm-waimea [ 173.272378] BUG: sleeping function called from invalid context 49: B 0a82c22 kvm-waimea [ 165.639282] BUG: sleeping function called from invalid context 50: B 76fd41e kvm-xgwo [ 1236.146262] BUG: sleeping function called from invalid context 51: B 7aff72a kvm-slim [ 1052.894214] BUG: sleeping function called from invalid context 51: B 7aff72a kvm-waimea [ 318.361556] BUG: sleeping function called from invalid context 51: B 7aff72a kvm-waimea [ 319.006427] BUG: sleeping function called from invalid context 51: B 7aff72a kvm-waimea [ 316.651432] BUG: sleeping function called from invalid context 51: B 7aff72a kvm-waimea [ 324.405158] BUG: sleeping function called from invalid context 51: B 7aff72a kvm-waimea [ 322.427800] BUG: sleeping function called from invalid context 51: B 7aff72a kvm-waimea [ 318.240169] BUG: sleeping function called from invalid context 51: B 7aff72a kvm-waimea [ 249.749861] BUG: sleeping function called from invalid context 51: B 7aff72a kvm-xgwo [ 1215.732446] BUG: sleeping function called from invalid context case-small-allocs-mt case-truncate [ 995.982449] BUG: sleeping function called from invalid context at /c/kernel-tests/src/stable/kernel/mutex.c:269 [ 995.993807] in_atomic(): 1, irqs_disabled(): 0, pid: 4795, name: umount [ 996.001491] 1 lock held by umount/4795: [ 996.006358] #0: (sb_lock){+.+.-.}, at: [] put_super+0x1a/0x32 [ 996.013847] Pid: 4795, comm: umount Not tainted 3.5.0-rc6+ #63 [ 996.017888] Call Trace: [ 996.020450] [] __might_sleep+0x107/0x10c [ 996.024074] [] mutex_lock_nested+0x41/0x315 [ 996.027416] [] ? _raw_spin_unlock_irqrestore+0x47/0x65 [ 996.031181] [] ? trace_hardirqs_on_caller+0x125/0x181 [ 996.035415] [] percpu_counter_destroy+0x1e/0x48 [ 996.039401] [] destroy_sb_writers+0x1b/0x37 [ 996.043161] [] __put_super+0x36/0x7b [ 996.046590] [] ? put_super+0x1a/0x32 [ 996.050098] [] put_super+0x22/0x32 [ 996.053322] [] deactivate_locked_super+0x47/0x57 [ 996.056870] [] deactivate_super+0x41/0x45 [ 996.060170] [] mntput_no_expire+0x112/0x11b [ 996.063529] [] sys_umount+0x2f4/0x30f [ 996.066975] [] tracesys+0xdd/0xe2 Thanks, Fengguang