kernel_optimize_test/drivers
Daniel Vetter 5c6c201ccb drm: Paper over locking inversion after registration rework
drm_connector_register_all requires a few too many locks because our
connector_list locking is busted. Add another FIXME+hack to work
around this. This should address the below lockdep splat:

======================================================
[ INFO: possible circular locking dependency detected ]
4.7.0-rc5+ #524 Tainted: G           O
-------------------------------------------------------
kworker/u8:0/6 is trying to acquire lock:
 (&dev->mode_config.mutex){+.+.+.}, at: [<ffffffff815afde0>] drm_modeset_lock_all+0x40/0x120

but task is already holding lock:
 ((fb_notifier_list).rwsem){++++.+}, at: [<ffffffff810ac195>] __blocking_notifier_call_chain+0x35/0x70

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 ((fb_notifier_list).rwsem){++++.+}:
       [<ffffffff810df611>] lock_acquire+0xb1/0x200
       [<ffffffff819a55b4>] down_write+0x44/0x80
       [<ffffffff810abf91>] blocking_notifier_chain_register+0x21/0xb0
       [<ffffffff814c7448>] fb_register_client+0x18/0x20
       [<ffffffff814c6c86>] backlight_device_register+0x136/0x260
       [<ffffffffa0127eb2>] intel_backlight_device_register+0xa2/0x160 [i915]
       [<ffffffffa00f46be>] intel_connector_register+0xe/0x10 [i915]
       [<ffffffffa0112bfb>] intel_dp_connector_register+0x1b/0x80 [i915]
       [<ffffffff8159dfea>] drm_connector_register+0x4a/0x80
       [<ffffffff8159fe44>] drm_connector_register_all+0x64/0xf0
       [<ffffffff815a2a64>] drm_modeset_register_all+0x174/0x1c0
       [<ffffffff81599b72>] drm_dev_register+0xc2/0xd0
       [<ffffffffa00621d7>] i915_driver_load+0x1547/0x2200 [i915]
       [<ffffffffa006d80f>] i915_pci_probe+0x4f/0x70 [i915]
       [<ffffffff814a2135>] local_pci_probe+0x45/0xa0
       [<ffffffff814a349b>] pci_device_probe+0xdb/0x130
       [<ffffffff815c07e3>] driver_probe_device+0x223/0x440
       [<ffffffff815c0ad5>] __driver_attach+0xd5/0x100
       [<ffffffff815be386>] bus_for_each_dev+0x66/0xa0
       [<ffffffff815c002e>] driver_attach+0x1e/0x20
       [<ffffffff815bf9be>] bus_add_driver+0x1ee/0x280
       [<ffffffff815c1810>] driver_register+0x60/0xe0
       [<ffffffff814a1a10>] __pci_register_driver+0x60/0x70
       [<ffffffffa01a905b>] i915_init+0x5b/0x62 [i915]
       [<ffffffff8100042d>] do_one_initcall+0x3d/0x150
       [<ffffffff811a935b>] do_init_module+0x5f/0x1d9
       [<ffffffff81124416>] load_module+0x20e6/0x27e0
       [<ffffffff81124d63>] SYSC_finit_module+0xc3/0xf0
       [<ffffffff81124dae>] SyS_finit_module+0xe/0x10
       [<ffffffff819a83a9>] entry_SYSCALL_64_fastpath+0x1c/0xac

-> #0 (&dev->mode_config.mutex){+.+.+.}:
       [<ffffffff810df0ac>] __lock_acquire+0x10fc/0x1260
       [<ffffffff810df611>] lock_acquire+0xb1/0x200
       [<ffffffff819a3097>] mutex_lock_nested+0x67/0x3c0
       [<ffffffff815afde0>] drm_modeset_lock_all+0x40/0x120
       [<ffffffff8158f79b>] drm_fb_helper_restore_fbdev_mode_unlocked+0x2b/0x80
       [<ffffffff8158f81d>] drm_fb_helper_set_par+0x2d/0x50
       [<ffffffffa0105f7a>] intel_fbdev_set_par+0x1a/0x60 [i915]
       [<ffffffff814c13c6>] fbcon_init+0x586/0x610
       [<ffffffff8154d16a>] visual_init+0xca/0x130
       [<ffffffff8154e611>] do_bind_con_driver+0x1c1/0x3a0
       [<ffffffff8154eaf6>] do_take_over_console+0x116/0x180
       [<ffffffff814bd3a7>] do_fbcon_takeover+0x57/0xb0
       [<ffffffff814c1e48>] fbcon_event_notify+0x658/0x750
       [<ffffffff810abcae>] notifier_call_chain+0x3e/0xb0
       [<ffffffff810ac1ad>] __blocking_notifier_call_chain+0x4d/0x70
       [<ffffffff810ac1e6>] blocking_notifier_call_chain+0x16/0x20
       [<ffffffff814c748b>] fb_notifier_call_chain+0x1b/0x20
       [<ffffffff814c86b1>] register_framebuffer+0x251/0x330
       [<ffffffff8158fa9f>] drm_fb_helper_initial_config+0x25f/0x3f0
       [<ffffffffa0106b48>] intel_fbdev_initial_config+0x18/0x30 [i915]
       [<ffffffff810adfd8>] async_run_entry_fn+0x48/0x150
       [<ffffffff810a3947>] process_one_work+0x1e7/0x750
       [<ffffffff810a3efb>] worker_thread+0x4b/0x4f0
       [<ffffffff810aad4f>] kthread+0xef/0x110
       [<ffffffff819a85ef>] ret_from_fork+0x1f/0x40

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock((fb_notifier_list).rwsem);
                               lock(&dev->mode_config.mutex);
                               lock((fb_notifier_list).rwsem);
  lock(&dev->mode_config.mutex);

 *** DEADLOCK ***

6 locks held by kworker/u8:0/6:
 #0:  ("events_unbound"){.+.+.+}, at: [<ffffffff810a38c9>] process_one_work+0x169/0x750
 #1:  ((&entry->work)){+.+.+.}, at: [<ffffffff810a38c9>] process_one_work+0x169/0x750
 #2:  (registration_lock){+.+.+.}, at: [<ffffffff814c8487>] register_framebuffer+0x27/0x330
 #3:  (console_lock){+.+.+.}, at: [<ffffffff814c86ce>] register_framebuffer+0x26e/0x330
 #4:  (&fb_info->lock){+.+.+.}, at: [<ffffffff814c78dd>] lock_fb_info+0x1d/0x40
 #5:  ((fb_notifier_list).rwsem){++++.+}, at: [<ffffffff810ac195>] __blocking_notifier_call_chain+0x35/0x70

stack backtrace:
CPU: 2 PID: 6 Comm: kworker/u8:0 Tainted: G           O    4.7.0-rc5+ #524
Hardware name: Intel Corp. Broxton P/NOTEBOOK, BIOS APLKRVPA.X64.0138.B33.1606250842 06/25/2016
Workqueue: events_unbound async_run_entry_fn
 0000000000000000 ffff8800758577f0 ffffffff814507a5 ffffffff828b9900
 ffffffff828b9900 ffff880075857830 ffffffff810dc6fa ffff880075857880
 ffff88007584d688 0000000000000005 0000000000000006 ffff88007584d6b0
Call Trace:
 [<ffffffff814507a5>] dump_stack+0x67/0x92
 [<ffffffff810dc6fa>] print_circular_bug+0x1aa/0x200
 [<ffffffff810df0ac>] __lock_acquire+0x10fc/0x1260
 [<ffffffff810df611>] lock_acquire+0xb1/0x200
 [<ffffffff815afde0>] ? drm_modeset_lock_all+0x40/0x120
 [<ffffffff815afde0>] ? drm_modeset_lock_all+0x40/0x120
 [<ffffffff819a3097>] mutex_lock_nested+0x67/0x3c0
 [<ffffffff815afde0>] ? drm_modeset_lock_all+0x40/0x120
 [<ffffffff810fa85f>] ? rcu_read_lock_sched_held+0x7f/0x90
 [<ffffffff81208218>] ? kmem_cache_alloc_trace+0x248/0x2b0
 [<ffffffff815afdc5>] ? drm_modeset_lock_all+0x25/0x120
 [<ffffffff815afde0>] drm_modeset_lock_all+0x40/0x120
 [<ffffffff8158f79b>] drm_fb_helper_restore_fbdev_mode_unlocked+0x2b/0x80
 [<ffffffff8158f81d>] drm_fb_helper_set_par+0x2d/0x50
 [<ffffffffa0105f7a>] intel_fbdev_set_par+0x1a/0x60 [i915]
 [<ffffffff814c13c6>] fbcon_init+0x586/0x610
 [<ffffffff8154d16a>] visual_init+0xca/0x130
 [<ffffffff8154e611>] do_bind_con_driver+0x1c1/0x3a0
 [<ffffffff8154eaf6>] do_take_over_console+0x116/0x180
 [<ffffffff814bd3a7>] do_fbcon_takeover+0x57/0xb0
 [<ffffffff814c1e48>] fbcon_event_notify+0x658/0x750
 [<ffffffff810abcae>] notifier_call_chain+0x3e/0xb0
 [<ffffffff810ac1ad>] __blocking_notifier_call_chain+0x4d/0x70
 [<ffffffff810ac1e6>] blocking_notifier_call_chain+0x16/0x20
 [<ffffffff814c748b>] fb_notifier_call_chain+0x1b/0x20
 [<ffffffff814c86b1>] register_framebuffer+0x251/0x330
 [<ffffffff815b7e8d>] ? vga_switcheroo_client_fb_set+0x5d/0x70
 [<ffffffff8158fa9f>] drm_fb_helper_initial_config+0x25f/0x3f0
 [<ffffffffa0106b48>] intel_fbdev_initial_config+0x18/0x30 [i915]
 [<ffffffff810adfd8>] async_run_entry_fn+0x48/0x150
 [<ffffffff810a3947>] process_one_work+0x1e7/0x750
 [<ffffffff810a38c9>] ? process_one_work+0x169/0x750
 [<ffffffff810a3efb>] worker_thread+0x4b/0x4f0
 [<ffffffff810a3eb0>] ? process_one_work+0x750/0x750
 [<ffffffff810aad4f>] kthread+0xef/0x110
 [<ffffffff819a85ef>] ret_from_fork+0x1f/0x40
 [<ffffffff810aac60>] ? kthread_stop+0x2e0/0x2e0

v2: Rebase onto the right branch (hand-editing patches ftw) and add more
reporters.

Reported-by: Imre Deak <imre.deak@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Reported-by: Jiri Kosina <jikos@kernel.org>
Cc: Jiri Kosina <jikos@kernel.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-08-08 16:08:25 +10:00
..
accessibility
acpi More ACPI updates for v4.8-rc1 2016-08-05 23:29:05 -04:00
amba
android
ata New LED class driver: 2016-07-27 14:03:52 -07:00
atm drivers: atm: nicstar: Use the correct function to free some resources 2016-07-19 11:30:26 -07:00
auxdisplay
base More power management updates for v4.8-rc1 2016-08-05 23:26:16 -04:00
bcma wireless-drivers-next patches for 4.8 2016-07-25 11:09:19 -07:00
block block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
bluetooth Bluetooth: btmrvl: reset is_suspending flag in failure path 2016-07-18 10:13:02 +02:00
bus ARM: SoC driver updates for v4.8 2016-08-01 18:36:01 -04:00
cdrom
char RTC for 4.8 2016-08-05 09:48:22 -04:00
clk treewide: replace obsolete _refok by __ref 2016-08-02 17:31:41 -04:00
clocksource ARM: SoC driver updates for v4.8 2016-08-01 18:36:01 -04:00
connector
cpufreq More power management updates for v4.8-rc1 2016-08-05 23:26:16 -04:00
cpuidle powerpc updates for 4.8 # 1 2016-07-30 21:01:36 -07:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2016-08-01 14:28:42 -04:00
dax
dca
devfreq
dio
dma dmaengine updates for 4.8-rc1 2016-07-28 15:45:17 -07:00
dma-buf dma-buf: Release module reference on creation failure 2016-07-18 14:10:49 +02:00
edac * Altera Arria10 ethernet FIFO buffer support (Thor Thayer) 2016-07-27 13:40:47 -07:00
eisa
extcon
firewire
firmware tree-wide: replace config_enabled() with IS_ENABLED() 2016-08-04 08:50:07 -04:00
fmc
fpga drivers/fpga/Kconfig: fix build failure 2016-08-04 08:50:07 -04:00
gpio This is the bulk of GPIO changes for the v4.8 kernel cycle. 2016-07-26 19:16:01 -07:00
gpu drm: Paper over locking inversion after registration rework 2016-08-08 16:08:25 +10:00
hid Merge branch 'for-4.8/hid-led' into for-linus 2016-07-28 10:49:23 +02:00
hsi
hv
hwmon hwmon updates for v4.8 (take 2) 2016-08-01 16:49:13 -04:00
hwspinlock
hwtracing Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-07-29 13:55:30 -07:00
i2c powerpc updates for 4.8 # 1 2016-07-30 21:01:36 -07:00
ide Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide 2016-07-29 13:29:06 -07:00
idle Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-07-30 12:56:26 -07:00
iio
infiniband Second round of merge items for 4.8 2016-08-04 20:26:31 -04:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2016-08-05 23:24:15 -04:00
iommu dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
ipack
irqchip tree-wide: replace config_enabled() with IS_ENABLED() 2016-08-04 08:50:07 -04:00
isdn
leds powerpc updates for 4.8 # 1 2016-07-30 21:01:36 -07:00
lguest
lightnvm block: get rid of bio_rw and READA 2016-07-20 17:37:01 -06:00
macintosh powerpc updates for 4.8 # 1 2016-07-30 21:01:36 -07:00
mailbox mailbox: Fix format and type mismatches in Broadcom PDC driver 2016-07-28 21:27:31 +05:30
mcb
md block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
media media updates for v4.8-rc1 2016-08-04 09:59:37 -04:00
memory MTD updates for v4.8: 2016-08-02 17:05:11 -04:00
memstick memstick: don't allocate unused major for ms_block 2016-08-02 17:31:41 -04:00
message
mfd ARM: SoC driver updates for v4.8 2016-08-01 18:36:01 -04:00
misc virtio/vhost: new features for 4.8 2016-08-06 09:20:13 -04:00
mmc MMC core: 2016-07-31 21:36:58 -04:00
mtd This pull request contains mostly cleanups and minor 2016-08-04 19:51:49 -04:00
net virtio/vhost: new features for 4.8 2016-08-06 09:20:13 -04:00
nfc NFC 4.8 pull request 2016-07-20 23:39:36 -07:00
ntb NTB: ntb_hw_intel: use local variable pdev 2016-08-05 10:34:13 -04:00
nubus
nvdimm block: rename bio bi_rw to bi_opf 2016-08-07 14:41:02 -06:00
nvme PCI changes for the v4.8 merge window: 2016-08-02 17:12:29 -04:00
nvmem
of ramoops: use DT reserved-memory bindings 2016-08-05 11:21:36 -07:00
oprofile
parisc dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
parport
pci ACPI / hotplug / PCI: Runtime resume bridges before bus rescans 2016-08-04 21:33:58 -04:00
pcmcia
perf Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-07-29 13:55:30 -07:00
phy MMC core: 2016-07-31 21:36:58 -04:00
pinctrl This is the bulk of pin control changes for the v4.8 kernel cycle. 2016-07-28 17:06:51 -07:00
platform pwm: Changes for v4.8-rc1 2016-08-06 00:01:33 -04:00
pnp PNP: pnpbios: add header file to fix build errors 2016-07-27 18:52:54 +02:00
power ARM: SoC driver updates for v4.8 2016-08-01 18:36:01 -04:00
powercap
pps pps: do not crash when failed to register 2016-07-23 10:25:54 +09:00
ps3
ptp
pwm pwm: Changes for v4.8-rc1 2016-08-06 00:01:33 -04:00
rapidio rapidio/switches: add driver for IDT gen3 switches 2016-08-02 19:35:38 -04:00
ras
regulator pwm: Changes for v4.8-rc1 2016-08-06 00:01:33 -04:00
remoteproc dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
reset
rpmsg
rtc RTC for 4.8 2016-08-05 09:48:22 -04:00
s390 - ARM: GICv3 ITS emulation and various fixes. Removal of the old 2016-08-02 16:11:27 -04:00
sbus
scsi SCSI misc on 20160805 2016-08-05 23:47:27 -04:00
sfi
sh
sn
soc ARM: SoC driver updates for v4.8 2016-08-01 18:36:01 -04:00
spi ARM: DT updates for v4.8 2016-08-01 18:37:45 -04:00
spmi
ssb
staging Merge branch 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-08-07 10:01:14 -04:00
target target: iblock_execute_sync_cache() should use bio_set_op_attrs() 2016-08-07 14:41:02 -06:00
tc
thermal
thunderbolt
tty tree-wide: replace config_enabled() with IS_ENABLED() 2016-08-04 08:50:07 -04:00
uio
usb More USB patches for 4.8-rc1 2016-08-05 23:07:43 -04:00
uwb
vfio vfio: platform: check reset call return code during release 2016-07-19 10:54:45 -06:00
vhost virtio/vhost: new features for 4.8 2016-08-06 09:20:13 -04:00
video dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
virt
virtio virtio/vhost: new features for 4.8 2016-08-06 09:20:13 -04:00
vlynq
vme
w1 w1:omap_hdq: fix regression 2016-08-02 19:35:40 -04:00
watchdog watchdog: gpio_wdt: Fix missing platform_set_drvdata() in gpio_wdt_probe() 2016-07-27 10:47:43 +02:00
xen dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
zorro
Kconfig
Makefile virtio/vhost: new features for 4.8 2016-08-06 09:20:13 -04:00