<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - [CI] igt@* - dmesg-warn - WARNING: possible circular locking dependency detected" href="https://bugs.freedesktop.org/show_bug.cgi?id=103950#c2">Comment # 2</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - [CI] igt@* - dmesg-warn - WARNING: possible circular locking dependency detected" href="https://bugs.freedesktop.org/show_bug.cgi?id=103950">bug 103950</a> from <a class="email" href="mailto:marta.lofstedt@intel.com" title="Marta Löfstedt <marta.lofstedt@intel.com>"> Marta Löfstedt</a> <pre><a href="https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_3397/shard-hsw1/igt@pm_rpm@system-suspend-modeset.html">https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_3397/shard-hsw1/igt@pm_rpm@system-suspend-modeset.html</a> [ 82.002286] Suspending console(s) (use no_console_suspend to debug) [ 82.012503] sd 1:0:0:0: [sda] Synchronizing SCSI cache [ 82.021134] sd 1:0:0:0: [sda] Stopping disk [ 82.162690] ====================================================== [ 82.162690] WARNING: possible circular locking dependency detected [ 82.162692] 4.15.0-rc1-CI-CI_DRM_3397+ #1 Tainted: G U [ 82.162692] ------------------------------------------------------ [ 82.162693] watchdog/1/15 is trying to acquire lock: [ 82.162693] (&cpuctx_mutex){+.+.}, at: [<ffffffff8116071c>] perf_event_ctx_lock_nested+0xbc/0x1d0 [ 82.162698] but now in release context of a crosslock acquired at the following: [ 82.162699] ((completion)&self->parked){+.+.}, at: [<ffffffff8109d69d>] kthread_park+0x3d/0x50 [ 82.162702] which lock already depends on the new lock. [ 82.162702] the existing dependency chain (in reverse order) is: [ 82.162702] -> #3 ((completion)&self->parked){+.+.}: [ 82.162707] wait_for_common+0x54/0x210 [ 82.162707] kthread_park+0x3d/0x50 [ 82.162742] i915_gem_reset_prepare_engine+0x1d/0x90 [i915] [ 82.162764] i915_gem_reset_prepare+0x2c/0x60 [i915] [ 82.162780] i915_reset+0x66/0x230 [i915] [ 82.162796] i915_reset_device+0x1cb/0x230 [i915] [ 82.162812] i915_handle_error+0x2d3/0x430 [i915] [ 82.162835] hangcheck_declare_hang+0xc0/0xd0 [i915] [ 82.162857] i915_hangcheck_elapsed+0x275/0x2f0 [i915] [ 82.162859] process_one_work+0x227/0x650 [ 82.162860] worker_thread+0x48/0x3a0 [ 82.162861] kthread+0x139/0x170 [ 82.162862] ret_from_fork+0x24/0x30 [ 82.162863] -> #2 (&dev->struct_mutex){+.+.}: [ 82.162866] __mutex_lock+0x81/0x9b0 [ 82.162886] i915_mutex_lock_interruptible+0x47/0x130 [i915] [ 82.162907] i915_gem_fault+0x201/0x760 [i915] [ 82.162909] __do_fault+0x15/0x70 [ 82.162910] __handle_mm_fault+0x9ab/0xda0 [ 82.162912] handle_mm_fault+0x14f/0x2f0 [ 82.162913] __do_page_fault+0x2d1/0x560 [ 82.162914] page_fault+0x22/0x30 [ 82.162914] -> #1 (&mm->mmap_sem){++++}: [ 82.162917] __might_fault+0x63/0x90 [ 82.162919] _copy_to_user+0x1e/0x70 [ 82.162920] perf_read+0x1aa/0x290 [ 82.162921] __vfs_read+0x1e/0x120 [ 82.162922] vfs_read+0xa1/0x150 [ 82.162923] SyS_read+0x40/0xa0 [ 82.162924] entry_SYSCALL_64_fastpath+0x1c/0x89 [ 82.162924] -> #0 (&cpuctx_mutex){+.+.}: [ 82.162926] perf_event_ctx_lock_nested+0xbc/0x1d0 [ 82.162926] other info that might help us debug this: [ 82.162927] Chain exists of: &cpuctx_mutex --> &dev->struct_mutex --> (completion)&self->parked [ 82.162929] Possible unsafe locking scenario by crosslock: [ 82.162929] CPU0 CPU1 [ 82.162930] ---- ---- [ 82.162930] lock(&dev->struct_mutex); [ 82.162931] lock((completion)&self->parked); [ 82.162932] lock(&cpuctx_mutex); [ 82.162932] unlock((completion)&self->parked); [ 82.162933] *** DEADLOCK *** [ 82.162934] 1 lock held by watchdog/1/15: [ 82.162934] #0: (&x->wait){....}, at: [<ffffffff810c7b03>] complete+0x13/0x50 [ 82.162938] stack backtrace: [ 82.162939] CPU: 1 PID: 15 Comm: watchdog/1 Tainted: G U 4.15.0-rc1-CI-CI_DRM_3397+ #1 [ 82.162940] Hardware name: MSI MS-7924/Z97M-G43(MS-7924), BIOS V1.12 02/15/2016 [ 82.162940] Call Trace: [ 82.162944] dump_stack+0x5f/0x86 [ 82.162947] print_circular_bug+0x230/0x3b0 [ 82.162949] check_prev_add+0x439/0x7b0 [ 82.162951] ? HARDIRQ_verbose+0x10/0x10 [ 82.162954] ? lock_commit_crosslock+0x3e8/0x640 [ 82.162955] lock_commit_crosslock+0x3e8/0x640 [ 82.162956] ? __kthread_parkme+0x39/0x90 [ 82.162958] ? smpboot_thread_fn+0x184/0x270 [ 82.162960] complete+0x1f/0x50 [ 82.162961] ? __kthread_parkme+0x39/0x90 [ 82.162962] __kthread_parkme+0x63/0x90 [ 82.162964] ? smpboot_thread_fn+0x2c/0x270 [ 82.162965] smpboot_thread_fn+0xaa/0x270 [ 82.162966] kthread+0x139/0x170 [ 82.162968] ? sort_range+0x20/0x20 [ 82.162969] ? kthread_create_on_node+0x40/0x40 [ 82.162970] ret_from_fork+0x24/0x30 [ 82.196456] IRQ 31: no longer affine to CPU3</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> <li>You are the assignee for the bug.</li> <li>You are on the CC list for the bug.</li> </ul> </body> </html>