Hi, I and some others hit a similiar problem in Linux-Next (next-20130118), please see [1] and [2]. [3] has a interim analyze of my problems. After suspecting the problem was caused by TTY-NEXT, it turned out to be a JBD2 problem finally. The freezer/pm_test was helpful to hit the issue (Thanks Rafael for the hint!). So, the issue has two faces: TTY and JBD2. [4] gives a list and URLs of the patches I had to apply to have a clean system again. After applying the two TTY patches (without Eric's JBD2-fix!) the call-trace after freezer/pm_test looked like this; [ 433.527986] PM: Syncing filesystems ... done. [ 433.843761] PM: Preparing system for mem sleep [ 436.306002] Freezing user space processes ... [ 456.304956] Freezing of tasks failed after 20.01 seconds (1 tasks refusing to freeze, wq_busy=0): [ 456.305060] Cache I/O D ffffffff8180d780 0 2132 1 0x00000004 [ 456.305065] ffff88007b9dfe18 0000000000000046 ffff88007b9dfdc8 0000000300000001 [ 456.305069] ffff880097e21720 ffff88007b9dffd8 ffff88007b9dffd8 ffff88007b9dffd8 [ 456.305072] ffff880119b32e40 ffff880097e21720 ffff88007b9dfe28 ffff880118077800 [ 456.305076] Call Trace: [ 456.305085] [<ffffffff816b7469>] schedule+0x29/0x70 [ 456.305089] [<ffffffff8129067d>] jbd2_log_wait_commit+0xcd/0x1a0 [ 456.305094] [<ffffffff8107eac0>] ? add_wait_queue+0x60/0x60 [ 456.305098] [<ffffffff812307a5>] ext4_sync_file+0x205/0x380 [ 456.305103] [<ffffffff811c43ad>] do_fsync+0x5d/0x90 [ 456.305108] [<ffffffff8119442b>] ? sys_write+0x6b/0xa0 [ 456.305111] [<ffffffff811c4790>] sys_fsync+0x10/0x20 [ 456.305114] [<ffffffff816c0edd>] system_call_fastpath+0x1a/0x1f [ 456.305122] [ 456.305124] Restarting tasks ... done. [ 456.315056] video LNXVIDEO:00: Restoring backlight state After applying Eric's patch [5], I could not hit the call-trace again. NOTE: The patch is from December 2012 and is not shipped in latest Linux-Next. The attached testcase script was helpful to force the call-trace. I have run 50 loops of it w/o an issue! Feel free to add a Reported-by/Tested-by. ( The issue kept me busy for the last days. ) Regards, - Sedat - [1] http://marc.info/?t=135283664600002&r=1&w=2 [2] http://marc.info/?t=135862023700004&r=1&w=2 [3] http://marc.info/?l=linux-kernel&m=135862010419101&w=2 [4] http://marc.info/?l=linux-next&m=135863550923093&w=2 [5] http://patchwork.ozlabs.org/patch/207237/
Attachment:
run_pm-test_v2.sh
Description: Bourne shell script
