lock order reversal in dmesg?

Hi All,

With one of the snapshots from Friday 1 June, I'm seeing more info in my dmesg
than I typically do. Has some extra debugging been turned on?

lock order reversal:
1st 0xffffff00bb0eecd8 vmmaplk (&map->lock) @ /usr/src/sys/uvm/uvm_fault.c:1441
2nd 0xffff800000081138 drmdevlk (&dev->struct_mutex) @
/usr/src/sys/dev/pci/drm/i915/i915_gem.c:1801
lock order "&dev->struct_mutex"(rwlock) -> "&map->lock"(rwlock) first seen at:
#0 witness_checkorder+0x494
#1 _rw_enter+0x56
#2 vm_map_lock_ln+0xac
#3 uvm_map+0x191
#4 km_alloc+0x15a
#5 bus_space_map+0x13b
#6 i915_alloc_ifp+0x99
#7 intel_gtt_chipset_setup+0x152
#8 intel_enable_gtt+0x18
#9 i915_gem_init_hw+0x36
#10 i915_gem_init+0x23e
#11 i915_driver_load+0xfb1
#12 inteldrm_attach+0x35b
#13 config_attach+0x1fe
#14 pci_probe_device+0x4e1
#15 pci_enumerate_bus+0xa7
#16 config_attach+0x1fe
#17 mainbus_attach+0x237
#18 config_attach+0x1fe
lock order "&map->lock"(rwlock) -> "&dev->struct_mutex"(rwlock) first seen at:
#0 witness_checkorder+0x494
#1 _rw_enter_write+0x53
#2 i915_gem_object_wait_rendering__nonblocking+0x1ea
#3 i915_gem_fault+0x137
#4 drm_fault+0x18a
#5 uvm_fault+0x733
#6 trap+0x509
#7 Xalltraps_untramp+0xec
lock order reversal:
1st 0xffffffff81ce85f8 &sched_lock (&sched_lock) @
/usr/src/sys/kern/kern_synch.c:444
2nd 0xffff80000007e270 &dev_priv->irq_lock (&dev_priv->irq_lock) @
/usr/src/sys/dev/pci/drm/i915/intel_ringbuffer.c:1672
lock order "&dev_priv->irq_lock"(mutex) -> "&sched_lock"(sched_lock) first
seen at:
#0 witness_checkorder+0x494
#1 ___mp_lock+0x70
#2 schedclock+0x30
#3 hardclock+0xd5
#4 lapic_clockintr+0x2f
#5 Xresume_lapic_ltimer+0x22
#6 x86_bus_space_mem_read_4+0x7
#7 i915_irq_handler+0x107
#8 intr_handler+0x68
#9 Xintr_ioapic_level11_untramp+0x141
#10 acpicpu_idle+0x232
#11 cpu_idle_cycle+0x10
lock order "&sched_lock"(sched_lock) -> "&dev_priv->irq_lock"(mutex) first
seen at:
#0 witness_checkorder+0x494
#1 _mtx_enter+0x31
#2 i9xx_ring_put_irq+0x35
#3 __i915_wait_request+0x344
#4 i915_gem_object_wait_rendering__nonblocking+0x1c6
#5 i915_gem_fault+0x137
#6 drm_fault+0x18a
#7 uvm_fault+0x733
#8 trap+0x509
#9 Xalltraps_untramp+0xec


Thanks!