Hi, Doing some testing on CFQ, I ran into this 100% reproducible report:
======================================================= [ INFO: possible circular locking dependency detected ] 2.6.21-rc7 #5 ------------------------------------------------------- fio/9741 is trying to acquire lock: (&mm->mmap_sem){----}, at: [<b018cb34>] dio_get_page+0x54/0x161 but task is already holding lock: (&inode->i_mutex){--..}, at: [<b038c6e5>] mutex_lock+0x1c/0x1f which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&inode->i_mutex){--..}: [<b013e3fb>] __lock_acquire+0xdee/0xf9c [<b013e600>] lock_acquire+0x57/0x70 [<b038c4a5>] __mutex_lock_slowpath+0x73/0x297 [<b038c6e5>] mutex_lock+0x1c/0x1f [<b01b17e9>] reiserfs_file_release+0x54/0x447 [<b016afe7>] __fput+0x53/0x101 [<b016b0ee>] fput+0x19/0x1c [<b015bcd5>] remove_vma+0x3b/0x4d [<b015c659>] do_munmap+0x17f/0x1cf [<b015c6db>] sys_munmap+0x32/0x42 [<b0103f04>] sysenter_past_esp+0x5d/0x99 [<ffffffff>] 0xffffffff -> #0 (&mm->mmap_sem){----}: [<b013e259>] __lock_acquire+0xc4c/0xf9c [<b013e600>] lock_acquire+0x57/0x70 [<b0137b92>] down_read+0x3a/0x4c [<b018cb34>] dio_get_page+0x54/0x161 [<b018d7a9>] __blockdev_direct_IO+0x514/0xe2a [<b01cf449>] ext3_direct_IO+0x98/0x1e5 [<b014e8df>] generic_file_direct_IO+0x63/0x133 [<b01500e9>] generic_file_aio_read+0x16b/0x222 [<b017f8b6>] aio_rw_vect_retry+0x5a/0x116 [<b0180147>] aio_run_iocb+0x69/0x129 [<b0180a78>] io_submit_one+0x194/0x2eb [<b0181331>] sys_io_submit+0x92/0xe7 [<b0103f90>] syscall_call+0x7/0xb [<ffffffff>] 0xffffffff other info that might help us debug this: 1 lock held by fio/9741: #0: (&inode->i_mutex){--..}, at: [<b038c6e5>] mutex_lock+0x1c/0x1f stack backtrace: [<b0104f54>] show_trace_log_lvl+0x1a/0x30 [<b0105626>] show_trace+0x12/0x14 [<b01056ad>] dump_stack+0x16/0x18 [<b013c48d>] print_circular_bug_tail+0x68/0x71 [<b013e259>] __lock_acquire+0xc4c/0xf9c [<b013e600>] lock_acquire+0x57/0x70 [<b0137b92>] down_read+0x3a/0x4c [<b018cb34>] dio_get_page+0x54/0x161 [<b018d7a9>] __blockdev_direct_IO+0x514/0xe2a [<b01cf449>] ext3_direct_IO+0x98/0x1e5 [<b014e8df>] generic_file_direct_IO+0x63/0x133 [<b01500e9>] generic_file_aio_read+0x16b/0x222 [<b017f8b6>] aio_rw_vect_retry+0x5a/0x116 [<b0180147>] aio_run_iocb+0x69/0x129 [<b0180a78>] io_submit_one+0x194/0x2eb [<b0181331>] sys_io_submit+0x92/0xe7 [<b0103f90>] syscall_call+0x7/0xb ======================= The test run was fio, the job file used is: # fio job file snip below [global] bs=4k buffered=0 ioengine=libaio iodepth=4 thread [readers] numjobs=8 size=128m rw=read # fio job file snip above Filesystem was ext3, default mkfs and mount options. Kernel was 2.6.21-rc7 as of this morning, with some CFQ patches applied. -- Jens Axboe - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/