I tried to suspend a computer running linux 3.11.1 while a scrub was going, and I got this: Oct 2 20:15:12 caper kernel: [ 1237.472716] PM: Preparing system for mem sleep Oct 2 20:15:12 caper kernel: [ 1237.472856] Freezing user space processes ... Oct 2 20:15:12 caper kernel: [ 1257.474848] Freezing of tasks failed after 20.004 seconds (2 tasks refusing to freeze, wq_busy=0): Oct 2 20:15:12 caper kernel: [ 1257.474947] btrfs D 0000000000000000 0 4709 1 0x00000004 Oct 2 20:15:12 caper kernel: [ 1257.474951] ffff8800888b9888 0000000000000002 ffff8800888b9888 0000000000000296 Oct 2 20:15:12 caper kernel: [ 1257.474953] ffff8800888b9fd8 ffff8800888b9fd8 ffff8800888b9fd8 0000000000014580 Oct 2 20:15:12 caper kernel: [ 1257.474956] ffffffff81c14440 ffff880134161770 ffff8800888b9898 ffff8800bf8f5300 Oct 2 20:15:12 caper kernel: [ 1257.474958] Call Trace: Oct 2 20:15:12 caper kernel: [ 1257.474965] [<ffffffff8172d3b9>] schedule+0x29/0x70 Oct 2 20:15:12 caper kernel: [ 1257.474994] [<ffffffffa014fa15>] scrub_add_page_to_rd_bio+0x1e5/0x2d0 [btrfs] Oct 2 20:15:12 caper kernel: [ 1257.474999] [<ffffffff81089ab0>] ? add_wait_queue+0x60/0x60 Oct 2 20:15:12 caper kernel: [ 1257.475012] [<ffffffffa0150b3c>] scrub_pages+0x1fc/0x2a0 [btrfs] Oct 2 20:15:12 caper kernel: [ 1257.475024] [<ffffffffa0150f35>] scrub_extent+0x115/0x230 [btrfs] Oct 2 20:15:12 caper kernel: [ 1257.475036] [<ffffffffa0151b01>] scrub_stripe+0xab1/0xd30 [btrfs] Oct 2 20:15:12 caper kernel: [ 1257.475046] [<ffffffffa00d84c7>] ? read_block_for_search.isra.47+0xa7/0x1d0 [btrfs] Oct 2 20:15:12 caper kernel: [ 1257.475058] [<ffffffffa0151ea3>] scrub_chunk.isra.14+0x123/0x150 [btrfs] Oct 2 20:15:12 caper kernel: [ 1257.475060] [<ffffffff8172e7de>] ? _raw_spin_lock+0xe/0x20 Oct 2 20:15:12 caper kernel: [ 1257.475072] [<ffffffffa0152150>] scrub_enumerate_chunks+0x280/0x5b0 [btrfs] Oct 2 20:15:12 caper kernel: [ 1257.475075] [<ffffffff81089a00>] ? add_wait_queue_exclusive+0x10/0x60 Oct 2 20:15:12 caper kernel: [ 1257.475087] [<ffffffffa0153378>] btrfs_scrub_dev+0x1a8/0x520 [btrfs] Oct 2 20:15:12 caper kernel: [ 1257.475099] [<ffffffffa012c2b8>] ? btrfs_ioctl_scrub+0x58/0x110 [btrfs] Oct 2 20:15:12 caper kernel: [ 1257.475102] [<ffffffff811d3018>] ? __mnt_want_write+0x58/0x70 Oct 2 20:15:12 caper kernel: [ 1257.475104] [<ffffffff811d30d1>] ? __mnt_want_write_file+0x51/0x60 Oct 2 20:15:12 caper kernel: [ 1257.475116] [<ffffffffa012c311>] btrfs_ioctl_scrub+0xb1/0x110 [btrfs] Oct 2 20:15:12 caper kernel: [ 1257.475129] [<ffffffffa013128c>] btrfs_ioctl+0x87c/0xa90 [btrfs] Oct 2 20:15:12 caper kernel: [ 1257.475132] [<ffffffff8109caf6>] ? account_user_time+0xa6/0xc0 Oct 2 20:15:12 caper kernel: [ 1257.475134] [<ffffffff8109d134>] ? vtime_account_user+0x74/0x90 Oct 2 20:15:12 caper kernel: [ 1257.475136] [<ffffffff811c5b7c>] do_vfs_ioctl+0x7c/0x2f0 Oct 2 20:15:12 caper kernel: [ 1257.475140] [<ffffffff810210a9>] ? syscall_trace_enter+0x29/0x270 Oct 2 20:15:12 caper kernel: [ 1257.475141] [<ffffffff811c5e81>] SyS_ioctl+0x91/0xb0 Oct 2 20:15:12 caper kernel: [ 1257.475144] [<ffffffff81737e2f>] tracesys+0xe1/0xe6 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html