Commits
Bjørn Mork committed 42bf7b46a5d
drm/i915: fix deadlock on lid open
commit e2c8b8701e2d moved modeset locking inside resume/suspend
functions, but missed a code path only executed on lid close/open
on older hardware. The result was a deadlock when closing and
opening the lid without suspending on such hardware:
=============================================
[ INFO: possible recursive locking detected ]
4.6.0-rc1 #385 Not tainted
---------------------------------------------
kworker/0:3/88 is trying to acquire lock:
(&dev->mode_config.mutex){+.+.+.}, at: [<ffffffffa063e6a4>] intel_display_resume+0x4a/0x12f [i915]
but task is already holding lock:
(&dev->mode_config.mutex){+.+.+.}, at: [<ffffffffa02d0d4f>] drm_modeset_lock_all+0x3e/0xa6 [drm]
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&dev->mode_config.mutex);
lock(&dev->mode_config.mutex);
*** DEADLOCK ***
May be due to missing lock nesting notation
7 locks held by kworker/0:3/88:
#0: ("kacpi_notify"){++++.+}, at: [<ffffffff81068dfc>] process_one_work+0x14a/0x50b
#1: ((&dpc->work)#2){+.+.+.}, at: [<ffffffff81068dfc>] process_one_work+0x14a/0x50b
#2: ((acpi_lid_notifier).rwsem){++++.+}, at: [<ffffffff8106f874>] __blocking_notifier_call_chain+0x34/0x65
#3: (&dev_priv->modeset_restore_lock){+.+.+.}, at: [<ffffffffa0664cf6>] intel_lid_notify+0x3c/0xd9 [i915]
#4: (&dev->mode_config.mutex){+.+.+.}, at: [<ffffffffa02d0d4f>] drm_modeset_lock_all+0x3e/0xa6 [drm]
#5: (crtc_ww_class_acquire){+.+.+.}, at: [<ffffffffa02d0d59>] drm_modeset_lock_all+0x48/0xa6 [drm]
#6: (crtc_ww_class_mutex){+.+.+.}, at: [<ffffffffa02d0b2a>] modeset_lock+0x13c/0x1cd [drm]
stack backtrace:
CPU: 0 PID: 88 Comm: kworker/0:3 Not tainted 4.6.0-rc1 #385
Hardware name: LENOVO 2776LEG/2776LEG, BIOS 6EET55WW (3.15 ) 12/19/2011
Workqueue: kacpi_notify acpi_os_execute_deferred
0000000000000000 ffff88022fd5f990 ffffffff8124af06 ffffffff825b39c0
ffffffff825b39c0 ffff88022fd5fa60 ffffffff8108f547 ffff88022fd5fa70
000000008108e817 ffff880230236cc0 0000000000000000 ffffffff825b39c0
Call Trace:
[<ffffffff8124af06>] dump_stack+0x67/0x90
[<ffffffff8108f547>] __lock_acquire+0xdb5/0xf71
[<ffffffff8108bd2c>] ? look_up_lock_class+0xbe/0x10a
[<ffffffff8108fae2>] lock_acquire+0x137/0x1cb
[<ffffffff8108fae2>] ? lock_acquire+0x137/0x1cb
[<ffffffffa063e6a4>] ? intel_display_resume+0x4a/0x12f [i915]
[<ffffffff8148202f>] mutex_lock_nested+0x7e/0x3a4
[<ffffffffa063e6a4>] ? intel_display_resume+0x4a/0x12f [i915]
[<ffffffffa063e6a4>] ? intel_display_resume+0x4a/0x12f [i915]
[<ffffffffa02d0b2a>] ? modeset_lock+0x13c/0x1cd [drm]
[<ffffffffa063e6a4>] intel_display_resume+0x4a/0x12f [i915]
[<ffffffffa063e6a4>] ? intel_display_resume+0x4a/0x12f [i915]
[<ffffffffa02d0b2a>] ? modeset_lock+0x13c/0x1cd [drm]
[<ffffffffa02d0b2a>] ? modeset_lock+0x13c/0x1cd [drm]
[<ffffffffa02d0bf7>] ? drm_modeset_lock+0x17/0x24 [drm]
[<ffffffffa02d0c8b>] ? drm_modeset_lock_all_ctx+0x87/0xa1 [drm]
[<ffffffffa0664d6a>] intel_lid_notify+0xb0/0xd9 [i915]
[<ffffffff8106f4c6>] notifier_call_chain+0x4a/0x6c
[<ffffffff8106f88d>] __blocking_notifier_call_chain+0x4d/0x65
[<ffffffff8106f8b9>] blocking_notifier_call_chain+0x14/0x16
[<ffffffffa0011215>] acpi_lid_send_state+0x83/0xad [button]
[<ffffffffa00112a6>] acpi_button_notify+0x41/0x132 [button]
[<ffffffff812b07df>] acpi_device_notify+0x19/0x1b
[<ffffffff812c8570>] acpi_ev_notify_dispatch+0x49/0x64
[<ffffffff812ab9fb>] acpi_os_execute_deferred+0x14/0x20
[<ffffffff81068f17>] process_one_work+0x265/0x50b
[<ffffffff810696f5>] worker_thread+0x1fc/0x2dd
[<ffffffff810694f9>] ? rescuer_thread+0x309/0x309
[<ffffffff810694f9>] ? rescuer_thread+0x309/0x309
[<ffffffff8106e2d6>] kthread+0xe0/0xe8
[<ffffffff8107bc47>] ? local_clock+0x19/0x22
[<ffffffff81484f42>] ret_from_fork+0x22/0x40
[<ffffffff8106e1f6>] ? kthread_create_on_node+0x1b5/0x1b5
Fixes: e2c8b8701e2d ("drm/i915: Use atomic helpers for suspend, v2.")
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1459328913-13719-1-git-send-email-bjorn@mork.no
(cherry picked from commit 9f54d4bd5808b5c892a44c539c126b71d299f341)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>