Well, I've cherry-picked this series for current upstream/master branch, and got this while performing another suspend try: === [ 62.415890] Freezing of tasks failed after 20.007 seconds (1 tasks refusing to freeze, wq_busy=0): [ 62.421150] xfsaild/dm-7 D 0 289 2 0x80000000 [ 62.425800] Call Trace: [ 62.428902] __schedule+0x239/0x870 [ 62.431834] schedule+0x33/0x90 [ 62.434156] _xfs_log_force+0x143/0x280 [xfs] [ 62.438767] ? schedule_timeout+0x188/0x390 [ 62.443592] ? wake_up_q+0x80/0x80 [ 62.446545] ? xfsaild+0x18d/0x780 [xfs] [ 62.449702] xfs_log_force+0x2c/0x90 [xfs] [ 62.453217] xfsaild+0x18d/0x780 [xfs] [ 62.456717] kthread+0x124/0x140 [ 62.459237] ? kthread+0x124/0x140 [ 62.461818] ? xfs_trans_ail_cursor_first+0x90/0x90 [xfs] [ 62.465146] ? kthread_create_on_node+0x70/0x70 [ 62.467331] ret_from_fork+0x25/0x30 [ 62.474386] Restarting kernel threads ... done. === After this it looks like the system tried to freeze anyway: === [ 62.478290] OOM killer enabled. [ 62.481711] Restarting tasks ... done. [ 62.488931] PM: suspend exit [ 62.491497] PM: suspend entry (s2idle) [ 62.493445] PM: Syncing filesystems ... done. [ 63.774220] Freezing user space processes ... (elapsed 0.001 seconds) done. [ 63.782707] OOM killer disabled. [ 63.785226] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done. [ 63.861548] sd 1:0:0:0: [sdb] Synchronizing SCSI cache [ 63.868153] sd 0:0:0:0: [sda] Synchronizing SCSI cache [ 63.868463] sd 1:0:0:0: [sdb] Stopping disk [ 63.873216] sd 0:0:0:0: [sda] Stopping disk === but got hung completely. After some time hung task was detected: === [ 247.531069] INFO: task systemd-sleep:663 blocked for more than 120 seconds. [ 247.535307] Not tainted 4.14.0-pf0 #1 [ 247.537820] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 247.541015] systemd-sleep D 0 663 1 0x00000000 [ 247.542706] Call Trace: [ 247.543386] __schedule+0x239/0x870 [ 247.544351] schedule+0x33/0x90 [ 247.545197] suspend_devices_and_enter+0x61b/0x890 [ 247.546539] ? wait_woken+0x80/0x80 [ 247.547517] pm_suspend+0x340/0x3b0 [ 247.548550] state_store+0x5a/0x90 [ 247.549646] kobj_attr_store+0xf/0x20 [ 247.550649] sysfs_kf_write+0x37/0x40 [ 247.551640] kernfs_fop_write+0x11c/0x1a0 [ 247.552708] __vfs_write+0x37/0x150 [ 247.553641] ? SYSC_newfstat+0x44/0x70 [ 247.554628] vfs_write+0xb1/0x1a0 [ 247.555509] SyS_write+0x55/0xc0 [ 247.556366] entry_SYSCALL_64_fastpath+0x1a/0xa5 [ 247.557667] RIP: 0033:0x7f56b74ec8d4 [ 247.558616] RSP: 002b:00007fff141c7738 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 247.560667] RAX: ffffffffffffffda RBX: 000055dd61863290 RCX: 00007f56b74ec8d4 [ 247.562639] RDX: 0000000000000007 RSI: 000055dd61864eb0 RDI: 0000000000000004 [ 247.564874] RBP: 00007f56b77b3240 R08: 000055dd61863370 R09: 00007f56b79c88c0 [ 247.566875] R10: 000000000000000a R11: 0000000000000246 R12: 0000000000000000 [ 247.569213] R13: 000055dd61863290 R14: 000055dd61863d08 R15: 00000000ffffffea === P.S. Current Ming's series is enough for 4.13 to not experience any issues like this. On středa 18. října 2017 17:27:14 CEST Bart Van Assche wrote: > I think this version (v10) has significant advantages over the most recent > patch series posted by Ming Lei to address suspend, resume and SPI domain > validation. So it would be appreciated if you could switch to this series > for testing suspend and resume.