Created attachment 949580 [details] boot log Description of problem: I was trying to reproduce nirik's suspend/resume hang. I get this instead, which seems unrelated, apart from the fact that it happens during suspend: Oct 22 16:24:42 fedora22 kernel: ====================================================== Oct 22 16:24:42 fedora22 kernel: [ INFO: possible circular locking dependency detected ] Oct 22 16:24:42 fedora22 kernel: 3.18.0-0.rc1.git0.1.fc22.x86_64+debug #1 Not tainted Oct 22 16:24:42 fedora22 kernel: ------------------------------------------------------- Oct 22 16:24:42 fedora22 kernel: systemd-sleep/1268 is trying to acquire lock: Oct 22 16:24:42 fedora22 kernel: (cpuidle_lock){+.+...}, at: [<ffffffff816ad537>] cpuidle_pause_and_lock+0x17/0x20 Oct 22 16:24:42 fedora22 kernel: but task is already holding lock: Oct 22 16:24:42 fedora22 kernel: (cpu_hotplug.lock#2){+.+.+.}, at: [<ffffffff810abf18>] cpu_hotplug_begin+0x58/0x90 Oct 22 16:24:42 fedora22 kernel: which lock already depends on the new lock. Oct 22 16:24:42 fedora22 kernel: the existing dependency chain (in reverse order) is: Oct 22 16:24:42 fedora22 kernel: -> #1 (cpu_hotplug.lock#2){+.+.+.}: Oct 22 16:24:42 fedora22 kernel: [<ffffffff8110d5b1>] lock_acquire+0xd1/0x2b0 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81860c8e>] mutex_lock_nested+0x7e/0x440 Oct 22 16:24:42 fedora22 kernel: [<ffffffff816ad717>] cpuidle_pause+0x17/0x30 Oct 22 16:24:42 fedora22 kernel: [<ffffffff8156dc2f>] dpm_suspend_noirq+0x5f/0x620 Oct 22 16:24:42 fedora22 kernel: [<ffffffff8111583e>] suspend_devices_and_enter+0x27e/0xc90 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81116757>] pm_suspend+0x507/0x580 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81114470>] state_store+0x80/0x100 Oct 22 16:24:42 fedora22 kernel: [<ffffffff8141fc4f>] kobj_attr_store+0xf/0x20 Oct 22 16:24:42 fedora22 kernel: [<ffffffff813046d9>] sysfs_kf_write+0x49/0x60 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81303a19>] kernfs_fop_write+0xf9/0x180 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81274f2a>] vfs_write+0xba/0x200 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81275a7c>] SyS_write+0x5c/0xd0 Oct 22 16:24:42 fedora22 kernel: [<ffffffff818663a9>] system_call_fastpath+0x12/0x17 Oct 22 16:24:42 fedora22 kernel: -> #0 (cpuidle_lock){+.+...}: Oct 22 16:24:42 fedora22 kernel: [<ffffffff8110cb77>] __lock_acquire+0x1c67/0x1df0 Oct 22 16:24:42 fedora22 kernel: [<ffffffff8110d5b1>] lock_acquire+0xd1/0x2b0 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81860c8e>] mutex_lock_nested+0x7e/0x440 Oct 22 16:24:42 fedora22 kernel: [<ffffffff816ad537>] cpuidle_pause_and_lock+0x17/0x20 Oct 22 16:24:42 fedora22 kernel: [<ffffffff814ef86f>] acpi_processor_hotplug+0x4f/0x8d Oct 22 16:24:42 fedora22 kernel: [<ffffffff814ed069>] acpi_cpu_soft_notify+0xc1/0x10b Oct 22 16:24:42 fedora22 kernel: [<ffffffff810d51c2>] notifier_call_chain+0x62/0x100 Oct 22 16:24:42 fedora22 kernel: [<ffffffff810d526e>] __raw_notifier_call_chain+0xe/0x10 Oct 22 16:24:42 fedora22 kernel: [<ffffffff810abde3>] cpu_notify+0x23/0x50 Oct 22 16:24:42 fedora22 kernel: [<ffffffff810ac108>] _cpu_up+0x178/0x190 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81850c07>] enable_nonboot_cpus+0xe7/0x490 Oct 22 16:24:42 fedora22 kernel: [<ffffffff8111599d>] suspend_devices_and_enter+0x3dd/0xc90 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81116757>] pm_suspend+0x507/0x580 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81114470>] state_store+0x80/0x100 Oct 22 16:24:42 fedora22 kernel: [<ffffffff8141fc4f>] kobj_attr_store+0xf/0x20 Oct 22 16:24:42 fedora22 kernel: [<ffffffff813046d9>] sysfs_kf_write+0x49/0x60 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81303a19>] kernfs_fop_write+0xf9/0x180 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81274f2a>] vfs_write+0xba/0x200 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81275a7c>] SyS_write+0x5c/0xd0 Oct 22 16:24:42 fedora22 kernel: [<ffffffff818663a9>] system_call_fastpath+0x12/0x17 Oct 22 16:24:42 fedora22 kernel: other info that might help us debug this: Oct 22 16:24:42 fedora22 kernel: Possible unsafe locking scenario: Oct 22 16:24:42 fedora22 kernel: CPU0 CPU1 Oct 22 16:24:42 fedora22 kernel: ---- ---- Oct 22 16:24:42 fedora22 kernel: lock(cpu_hotplug.lock#2); Oct 22 16:24:42 fedora22 kernel: lock(cpuidle_lock); Oct 22 16:24:42 fedora22 kernel: lock(cpu_hotplug.lock#2); Oct 22 16:24:42 fedora22 kernel: lock(cpuidle_lock); Oct 22 16:24:42 fedora22 kernel: *** DEADLOCK *** Oct 22 16:24:42 fedora22 kernel: 8 locks held by systemd-sleep/1268: Oct 22 16:24:42 fedora22 kernel: #0: (sb_writers#3){.+.+.+}, at: [<ffffffff81275013>] vfs_write+0x1a3/0x200 Oct 22 16:24:42 fedora22 kernel: #1: (&of->mutex){+.+.+.}, at: [<ffffffff813039e7>] kernfs_fop_write+0xc7/0x180 Oct 22 16:24:42 fedora22 kernel: #2: (s_active#107){.+.+.+}, at: [<ffffffff813039f0>] kernfs_fop_write+0xd0/0x180 Oct 22 16:24:42 fedora22 kernel: #3: (pm_mutex){+.+.+.}, at: [<ffffffff8111640c>] pm_suspend+0x1bc/0x580 Oct 22 16:24:42 fedora22 kernel: #4: (acpi_scan_lock){+.+.+.}, at: [<ffffffff814ab14a>] acpi_scan_lock_acquire+0x17/0x19 Oct 22 16:24:42 fedora22 kernel: #5: (cpu_add_remove_lock){+.+.+.}, at: [<ffffffff81850b44>] enable_nonboot_cpus+0x24/0x490 Oct 22 16:24:42 fedora22 kernel: #6: (cpu_hotplug.lock){++++++}, at: [<ffffffff810abec5>] cpu_hotplug_begin+0x5/0x90 Oct 22 16:24:42 fedora22 kernel: #7: (cpu_hotplug.lock#2){+.+.+.}, at: [<ffffffff810abf18>] cpu_hotplug_begin+0x58/0x90 Oct 22 16:24:42 fedora22 kernel: stack backtrace: Oct 22 16:24:42 fedora22 kernel: CPU: 0 PID: 1268 Comm: systemd-sleep Not tainted 3.18.0-0.rc1.git0.1.fc22.x86_64+debug #1 Oct 22 16:24:42 fedora22 kernel: Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Oct 22 16:24:42 fedora22 kernel: 0000000000000000 00000000f1153b98 ffff8800780ab998 ffffffff8185be1d Oct 22 16:24:42 fedora22 kernel: 0000000000000000 ffffffff82a9d600 ffff8800780ab9e8 ffffffff8185939c Oct 22 16:24:42 fedora22 kernel: 00000000001d6a40 ffff8800780aba48 ffff8800785bccc0 ffff8800785bd798 Oct 22 16:24:42 fedora22 kernel: Call Trace: Oct 22 16:24:42 fedora22 kernel: [<ffffffff8185be1d>] dump_stack+0x4e/0x68 Oct 22 16:24:42 fedora22 kernel: [<ffffffff8185939c>] print_circular_bug+0x203/0x214 Oct 22 16:24:42 fedora22 kernel: [<ffffffff8110cb77>] __lock_acquire+0x1c67/0x1df0 Oct 22 16:24:42 fedora22 kernel: [<ffffffff8106ac07>] ? kvm_clock_read+0x27/0x40 Oct 22 16:24:42 fedora22 kernel: [<ffffffff8110d5b1>] lock_acquire+0xd1/0x2b0 Oct 22 16:24:42 fedora22 kernel: [<ffffffff816ad537>] ? cpuidle_pause_and_lock+0x17/0x20 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81860c8e>] mutex_lock_nested+0x7e/0x440 Oct 22 16:24:42 fedora22 kernel: [<ffffffff816ad537>] ? cpuidle_pause_and_lock+0x17/0x20 Oct 22 16:24:42 fedora22 kernel: [<ffffffff814a6f21>] ? acpi_os_wait_semaphore+0xa4/0x17f Oct 22 16:24:42 fedora22 kernel: [<ffffffff816ad537>] ? cpuidle_pause_and_lock+0x17/0x20 Oct 22 16:24:42 fedora22 kernel: [<ffffffff814e923f>] ? acpi_ut_release_mutex+0xb2/0xba Oct 22 16:24:42 fedora22 kernel: [<ffffffff816ad537>] cpuidle_pause_and_lock+0x17/0x20 Oct 22 16:24:42 fedora22 kernel: [<ffffffff814ef86f>] acpi_processor_hotplug+0x4f/0x8d Oct 22 16:24:42 fedora22 kernel: [<ffffffff814ed069>] acpi_cpu_soft_notify+0xc1/0x10b Oct 22 16:24:42 fedora22 kernel: [<ffffffff810d51c2>] notifier_call_chain+0x62/0x100 Oct 22 16:24:42 fedora22 kernel: [<ffffffff810d526e>] __raw_notifier_call_chain+0xe/0x10 Oct 22 16:24:42 fedora22 kernel: [<ffffffff810abde3>] cpu_notify+0x23/0x50 Oct 22 16:24:42 fedora22 kernel: [<ffffffff810ac108>] _cpu_up+0x178/0x190 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81850c07>] enable_nonboot_cpus+0xe7/0x490 Oct 22 16:24:42 fedora22 kernel: [<ffffffff811155b2>] ? arch_suspend_enable_irqs+0x12/0x20 Oct 22 16:24:42 fedora22 kernel: [<ffffffff8111599d>] suspend_devices_and_enter+0x3dd/0xc90 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81116757>] pm_suspend+0x507/0x580 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81114470>] state_store+0x80/0x100 Oct 22 16:24:42 fedora22 kernel: [<ffffffff8141fc4f>] kobj_attr_store+0xf/0x20 Oct 22 16:24:42 fedora22 kernel: [<ffffffff813046d9>] sysfs_kf_write+0x49/0x60 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81303a19>] kernfs_fop_write+0xf9/0x180 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81274f2a>] vfs_write+0xba/0x200 Oct 22 16:24:42 fedora22 kernel: [<ffffffff81275a7c>] SyS_write+0x5c/0xd0 Oct 22 16:24:42 fedora22 kernel: [<ffffffff818663a9>] system_call_fastpath+0x12/0x17 Version-Release number of selected component (if applicable): How reproducible: 100% (during first suspend after boot) Steps to Reproduce: 1. systemctl suspend Actual results: suspend works, just that the warning is printed
Please try the 3.18.0-0.rc2.git1.1 kernel that is current building. There was an upstream RCU issue that was causing hangs for a number of people.
After updates I'm not seeing this anymore.