Daniel J Blueman
2013-Jan-03 12:56 UTC
[Nouveau] 3.8-rc2: EFI framebuffer lock inversion...
On 3.8-rc2 with lockdep enabled and dual-GPU setup (Macbook Pro
Retina), I see two releated lock inversion issues with the EFI
framebuffer, leading to possible deadlock: when X takes over from the
EFI framebuffer [1] and when nouveau releases the framebuffer when
being vgaswitcherood [2].
Let me know if you'd like any testing or analysis when I can get the time.
Many thanks,
Daniel
--- [1]
init: lightdm main process (950) terminated with status 1
=====================================================[ INFO: possible circular
locking dependency detected ]
3.8.0-rc2-expert #1 Not tainted
-------------------------------------------------------
Xorg/1193 is trying to acquire lock:
((fb_notifier_list).rwsem){++++.+}, at: [<ffffffff810697c1>]
__blocking_notifier_call_chain+0x51/0xc0
but task is already holding lock:
(console_lock){+.+.+.}, at: [<ffffffff81263f95>] do_fb_ioctl+0x2e5/0x5f0
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (console_lock){+.+.+.}:
[<ffffffff81090a61>] __lock_acquire+0x3a1/0xb60
[<ffffffff810916ea>] lock_acquire+0x5a/0x70
[<ffffffff810407a7>] console_lock+0x77/0x80
[<ffffffff812c6d84>] register_con_driver+0x34/0x140
[<ffffffff812c84e9>] take_over_console+0x29/0x60
[<ffffffff8126e76b>] fbcon_takeover+0x5b/0xb0
[<ffffffff81272bb5>] fbcon_event_notify+0x715/0x820
[<ffffffff810693a5>] notifier_call_chain+0x55/0x110
[<ffffffff810697d7>] __blocking_notifier_call_chain+0x67/0xc0
[<ffffffff81069841>] blocking_notifier_call_chain+0x11/0x20
[<ffffffff81262a16>] fb_notifier_call_chain+0x16/0x20
[<ffffffff81264c1d>] register_framebuffer+0x1bd/0x2f0
[<ffffffff81ac2bd4>] efifb_probe+0x40f/0x496
[<ffffffff81308dfe>] platform_drv_probe+0x3e/0x70
[<ffffffff81306dc6>] driver_probe_device+0x76/0x240
[<ffffffff81307033>] __driver_attach+0xa3/0xb0
[<ffffffff8130503d>] bus_for_each_dev+0x4d/0x90
[<ffffffff81306929>] driver_attach+0x19/0x20
[<ffffffff813064e0>] bus_add_driver+0x1a0/0x270
[<ffffffff813076c2>] driver_register+0x72/0x170
[<ffffffff81308671>] platform_driver_register+0x41/0x50
[<ffffffff81308696>] platform_driver_probe+0x16/0xa0
[<ffffffff81ac2ece>] efifb_init+0x273/0x292
[<ffffffff810002da>] do_one_initcall+0x11a/0x170
[<ffffffff8154187c>] kernel_init+0x11c/0x290
[<ffffffff8155acac>] ret_from_fork+0x7c/0xb0
-> #0 ((fb_notifier_list).rwsem){++++.+}:
[<ffffffff8108ff10>] validate_chain.isra.33+0x1000/0x10d0
[<ffffffff81090a61>] __lock_acquire+0x3a1/0xb60
[<ffffffff810916ea>] lock_acquire+0x5a/0x70
[<ffffffff81557ad7>] down_read+0x47/0x5c
[<ffffffff810697c1>] __blocking_notifier_call_chain+0x51/0xc0
[<ffffffff81069841>] blocking_notifier_call_chain+0x11/0x20
[<ffffffff81262a16>] fb_notifier_call_chain+0x16/0x20
[<ffffffff81263196>] fb_blank+0x36/0xc0
[<ffffffff81263fa7>] do_fb_ioctl+0x2f7/0x5f0
[<ffffffff812646e1>] fb_ioctl+0x41/0x50
[<ffffffff811209d7>] do_vfs_ioctl+0x97/0x580
[<ffffffff81120f0b>] sys_ioctl+0x4b/0x90
[<ffffffff8155ad56>] system_call_fastpath+0x1a/0x1f
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(console_lock);
lock((fb_notifier_list).rwsem);
lock(console_lock);
lock((fb_notifier_list).rwsem);
*** DEADLOCK ***
2 locks held by Xorg/1193:
#0: (&fb_info->lock){+.+.+.}, at: [<ffffffff81262ef1>]
lock_fb_info+0x21/0x60
#1: (console_lock){+.+.+.}, at: [<ffffffff81263f95>]
do_fb_ioctl+0x2e5/0x5f0
stack backtrace:
Pid: 1193, comm: Xorg Not tainted 3.8.0-rc2-expert #1
Call Trace:
[<ffffffff8154f6c6>] print_circular_bug+0x28e/0x29f
[<ffffffff8108ff10>] validate_chain.isra.33+0x1000/0x10d0
[<ffffffff81090a61>] __lock_acquire+0x3a1/0xb60
[<ffffffff8108d3a4>] ? __lock_is_held+0x54/0x80
[<ffffffff810916ea>] lock_acquire+0x5a/0x70
[<ffffffff810697c1>] ? __blocking_notifier_call_chain+0x51/0xc0
[<ffffffff81557ad7>] down_read+0x47/0x5c
[<ffffffff810697c1>] ? __blocking_notifier_call_chain+0x51/0xc0
[<ffffffff810697c1>] __blocking_notifier_call_chain+0x51/0xc0
[<ffffffff81069841>] blocking_notifier_call_chain+0x11/0x20
[<ffffffff81262a16>] fb_notifier_call_chain+0x16/0x20
[<ffffffff81263196>] fb_blank+0x36/0xc0
[<ffffffff81263fa7>] do_fb_ioctl+0x2f7/0x5f0
[<ffffffff810e8d1a>] ? mmap_region+0x1aa/0x620
[<ffffffff812646e1>] fb_ioctl+0x41/0x50
[<ffffffff811209d7>] do_vfs_ioctl+0x97/0x580
[<ffffffff8112c49a>] ? fget_light+0x3da/0x4d0
[<ffffffff8155ad7b>] ? sysret_check+0x1b/0x56
[<ffffffff81120f0b>] sys_ioctl+0x4b/0x90
[<ffffffff8122c03e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[<ffffffff8155ad56>] system_call_fastpath+0x1a/0x1f
[drm] Enabling RC6 states: RC6 on, RC6p on, RC6pp off
--- [2]
hda-intel 0000:01:00.1: Disabling via VGA-switcheroo
hda-intel 0000:01:00.1: Cannot lock devices!
VGA switcheroo: switched nouveau off
nouveau [ DRM] suspending fbcon...
=====================================================[ INFO: possible circular
locking dependency detected ]
3.8.0-rc2-expert #1 Not tainted
-------------------------------------------------------
sh/1017 is trying to acquire lock:
((fb_notifier_list).rwsem){++++.+}, at: [<ffffffff810697c1>]
__blocking_notifier_call_chain+0x51/0xc0
but task is already holding lock:
(console_lock){+.+.+.}, at: [<ffffffffa0204d35>]
nouveau_fbcon_set_suspend+0x25/0xc0 [nouveau]
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (console_lock){+.+.+.}:
[<ffffffff81090a61>] __lock_acquire+0x3a1/0xb60
[<ffffffff810916ea>] lock_acquire+0x5a/0x70
[<ffffffff810407a7>] console_lock+0x77/0x80
[<ffffffff812c6d84>] register_con_driver+0x34/0x140
[<ffffffff812c84e9>] take_over_console+0x29/0x60
[<ffffffff8126e76b>] fbcon_takeover+0x5b/0xb0
[<ffffffff81272bb5>] fbcon_event_notify+0x715/0x820
[<ffffffff810693a5>] notifier_call_chain+0x55/0x110
[<ffffffff810697d7>] __blocking_notifier_call_chain+0x67/0xc0
[<ffffffff81069841>] blocking_notifier_call_chain+0x11/0x20
[<ffffffff81262a16>] fb_notifier_call_chain+0x16/0x20
[<ffffffff81264c1d>] register_framebuffer+0x1bd/0x2f0
[<ffffffff81ac2bd4>] efifb_probe+0x40f/0x496
[<ffffffff81308dfe>] platform_drv_probe+0x3e/0x70
[<ffffffff81306dc6>] driver_probe_device+0x76/0x240
[<ffffffff81307033>] __driver_attach+0xa3/0xb0
[<ffffffff8130503d>] bus_for_each_dev+0x4d/0x90
[<ffffffff81306929>] driver_attach+0x19/0x20
[<ffffffff813064e0>] bus_add_driver+0x1a0/0x270
[<ffffffff813076c2>] driver_register+0x72/0x170
[<ffffffff81308671>] platform_driver_register+0x41/0x50
[<ffffffff81308696>] platform_driver_probe+0x16/0xa0
[<ffffffff81ac2ece>] efifb_init+0x273/0x292
[<ffffffff810002da>] do_one_initcall+0x11a/0x170
[<ffffffff8154187c>] kernel_init+0x11c/0x290
[<ffffffff8155acac>] ret_from_fork+0x7c/0xb0
-> #0 ((fb_notifier_list).rwsem){++++.+}:
[<ffffffff8108ff10>] validate_chain.isra.33+0x1000/0x10d0
[<ffffffff81090a61>] __lock_acquire+0x3a1/0xb60
[<ffffffff810916ea>] lock_acquire+0x5a/0x70
[<ffffffff81557ad7>] down_read+0x47/0x5c
[<ffffffff810697c1>] __blocking_notifier_call_chain+0x51/0xc0
[<ffffffff81069841>] blocking_notifier_call_chain+0x11/0x20
[<ffffffff81262a16>] fb_notifier_call_chain+0x16/0x20
[<ffffffff81263146>] fb_set_suspend+0x46/0x60
[<ffffffffa0204da2>] nouveau_fbcon_set_suspend+0x92/0xc0 [nouveau]
[<ffffffffa01f5451>] nouveau_do_suspend+0x51/0x200 [nouveau]
[<ffffffffa01f564f>] nouveau_pmops_suspend+0x2f/0x80 [nouveau]
[<ffffffffa01f723c>] nouveau_switcheroo_set_state+0x5c/0xc0 [nouveau]
[<ffffffff81300877>] vga_switchoff+0x17/0x40
[<ffffffff81300f1a>] vga_switcheroo_debugfs_write+0xca/0x380
[<ffffffff8110ec93>] vfs_write+0xa3/0x160
[<ffffffff8110ef9d>] sys_write+0x4d/0xa0
[<ffffffff8155ad56>] system_call_fastpath+0x1a/0x1f
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(console_lock);
lock((fb_notifier_list).rwsem);
lock(console_lock);
lock((fb_notifier_list).rwsem);
*** DEADLOCK ***
2 locks held by sh/1017:
#0: (vgasr_mutex){+.+.+.}, at: [<ffffffff81300ea7>]
vga_switcheroo_debugfs_write+0x57/0x380
#1: (console_lock){+.+.+.}, at: [<ffffffffa0204d35>]
nouveau_fbcon_set_suspend+0x25/0xc0 [nouveau]
stack backtrace:
Pid: 1017, comm: sh Not tainted 3.8.0-rc2-expert #1
Call Trace:
[<ffffffff8154f6c6>] print_circular_bug+0x28e/0x29f
[<ffffffff8108ff10>] validate_chain.isra.33+0x1000/0x10d0
[<ffffffff81090a61>] __lock_acquire+0x3a1/0xb60
[<ffffffff8108d3a4>] ? __lock_is_held+0x54/0x80
[<ffffffff810916ea>] lock_acquire+0x5a/0x70
[<ffffffff810697c1>] ? __blocking_notifier_call_chain+0x51/0xc0
[<ffffffff81557ad7>] down_read+0x47/0x5c
[<ffffffff810697c1>] ? __blocking_notifier_call_chain+0x51/0xc0
[<ffffffff810697c1>] __blocking_notifier_call_chain+0x51/0xc0
[<ffffffff81069841>] blocking_notifier_call_chain+0x11/0x20
[<ffffffff81262a16>] fb_notifier_call_chain+0x16/0x20
[<ffffffff81263146>] fb_set_suspend+0x46/0x60
[<ffffffff810407a7>] ? console_lock+0x77/0x80
[<ffffffffa0204d35>] ? nouveau_fbcon_set_suspend+0x25/0xc0 [nouveau]
[<ffffffffa0204da2>] nouveau_fbcon_set_suspend+0x92/0xc0 [nouveau]
[<ffffffffa01f5451>] nouveau_do_suspend+0x51/0x200 [nouveau]
[<ffffffffa01f564f>] nouveau_pmops_suspend+0x2f/0x80 [nouveau]
[<ffffffffa01f723c>] nouveau_switcheroo_set_state+0x5c/0xc0 [nouveau]
[<ffffffff81300877>] vga_switchoff+0x17/0x40
[<ffffffff81300f1a>] vga_switcheroo_debugfs_write+0xca/0x380
[<ffffffff8110ec93>] vfs_write+0xa3/0x160
[<ffffffff8110ef9d>] sys_write+0x4d/0xa0
[<ffffffff8155ad56>] system_call_fastpath+0x1a/0x1f
nouveau [ DRM] suspending display...
nouveau [ DRM] unpinning framebuffer(s)...
nouveau [ DRM] evicting buffers...
nouveau [ DRM] suspending client object trees...
tg3 0000:0a:00.0 eth0: Link is up at 1000 Mbps, full duplex
tg3 0000:0a:00.0 eth0: Flow control is on for TX and on for RX
nouveau E[ I2C][0000:01:00.0] AUXCH(3): begin idle timeout 0xffffffff
nouveau E[ I2C][0000:01:00.0] AUXCH(2): begin idle timeout 0xffffffff
nouveau E[ I2C][0000:01:00.0] AUXCH(1): begin idle timeout 0xffffffff
--
Daniel J Blueman
On Thu, 3 Jan 2013 20:56:30 +0800 Daniel J Blueman <daniel at quora.org> wrote:> On 3.8-rc2 with lockdep enabled and dual-GPU setup (Macbook Pro > Retina), I see two releated lock inversion issues with the EFI > framebuffer, leading to possible deadlock: when X takes over from the > EFI framebuffer [1] and when nouveau releases the framebuffer when > being vgaswitcherood [2]. > > Let me know if you'd like any testing or analysis when I can get the time.The fb layer locking was broken. I posted patches early December which should have fixed the ones we know about. ('fb: Rework locking to fix lock ordering on takeover'). Alan
Daniel J Blueman
2013-Jan-03 13:42 UTC
[Nouveau] 3.8-rc2: EFI framebuffer lock inversion...
On 3 January 2013 21:11, Alan Cox <alan at lxorguk.ukuu.org.uk> wrote:> On Thu, 3 Jan 2013 20:56:30 +0800 > Daniel J Blueman <daniel at quora.org> wrote: > >> On 3.8-rc2 with lockdep enabled and dual-GPU setup (Macbook Pro >> Retina), I see two releated lock inversion issues with the EFI >> framebuffer, leading to possible deadlock: when X takes over from the >> EFI framebuffer [1] and when nouveau releases the framebuffer when >> being vgaswitcherood [2]. >> >> Let me know if you'd like any testing or analysis when I can get the time. > > The fb layer locking was broken. I posted patches early December which > should have fixed the ones we know about. ('fb: Rework locking to fix > lock ordering on takeover').Superb work, Alan! The only patch I could find [1] (mid Nov) looks like it needs another sites updating, since we now see an i915 vs efifb lock ordering issue [2]. I can get some time next week to take a look if it helps. Thanks, Daniel --- [1] https://patchwork.kernel.org/patch/1757061/ --- [2] [drm] Memory usable by graphics device = 2048M checking generic (b0000000 1440000) vs hw (b0000000 10000000) fb: conflicting fb hw usage inteldrmfb vs EFI VGA - removing generic driver =====================================================[ INFO: possible circular locking dependency detected ] 3.8.0-rc2-expert+ #2 Not tainted ------------------------------------------------------- modprobe/603 is trying to acquire lock: (console_lock){+.+.+.}, at: [<ffffffff812c869f>] unbind_con_driver+0x3f/0x200 but task is already holding lock: ((fb_notifier_list).rwsem){++++.+}, at: [<ffffffff810697c1>] __blocking_notifier_call_chain+0x51/0xc0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 ((fb_notifier_list).rwsem){++++.+}: [<ffffffff81090a61>] __lock_acquire+0x3a1/0xb60 [<ffffffff810916ea>] lock_acquire+0x5a/0x70 [<ffffffff81557c97>] down_read+0x47/0x5c [<ffffffff810697c1>] __blocking_notifier_call_chain+0x51/0xc0 [<ffffffff81069841>] blocking_notifier_call_chain+0x11/0x20 [<ffffffff81262a16>] fb_notifier_call_chain+0x16/0x20 [<ffffffff81264c20>] register_framebuffer+0x1c0/0x300 [<ffffffff81ac2bd4>] efifb_probe+0x40f/0x496 [<ffffffff81308fbe>] platform_drv_probe+0x3e/0x70 [<ffffffff81306f86>] driver_probe_device+0x76/0x240 [<ffffffff813071f3>] __driver_attach+0xa3/0xb0 [<ffffffff813051fd>] bus_for_each_dev+0x4d/0x90 [<ffffffff81306ae9>] driver_attach+0x19/0x20 [<ffffffff813066a0>] bus_add_driver+0x1a0/0x270 [<ffffffff81307882>] driver_register+0x72/0x170 [<ffffffff81308831>] platform_driver_register+0x41/0x50 [<ffffffff81308856>] platform_driver_probe+0x16/0xa0 [<ffffffff81ac2ece>] efifb_init+0x273/0x292 [<ffffffff810002da>] do_one_initcall+0x11a/0x170 [<ffffffff81541a3c>] kernel_init+0x11c/0x290 [<ffffffff8155ae6c>] ret_from_fork+0x7c/0xb0 -> #0 (console_lock){+.+.+.}: [<ffffffff8108ff10>] validate_chain.isra.33+0x1000/0x10d0 [<ffffffff81090a61>] __lock_acquire+0x3a1/0xb60 [<ffffffff810916ea>] lock_acquire+0x5a/0x70 [<ffffffff810407a7>] console_lock+0x77/0x80 [<ffffffff812c869f>] unbind_con_driver+0x3f/0x200 [<ffffffff81272bc7>] fbcon_event_notify+0x447/0x8b0 [<ffffffff810693a5>] notifier_call_chain+0x55/0x110 [<ffffffff810697d7>] __blocking_notifier_call_chain+0x67/0xc0 [<ffffffff81069841>] blocking_notifier_call_chain+0x11/0x20 [<ffffffff81262a16>] fb_notifier_call_chain+0x16/0x20 [<ffffffff812647db>] do_unregister_framebuffer+0x5b/0x110 [<ffffffff81264a28>] do_remove_conflicting_framebuffers+0x158/0x190 [<ffffffff81264d9a>] remove_conflicting_framebuffers+0x3a/0x60 [<ffffffffa007dbe4>] i915_driver_load+0x7d4/0xe70 [i915] [<ffffffff812ee1ee>] drm_get_pci_dev+0x17e/0x2b0 [<ffffffffa0079616>] i915_pci_probe+0x36/0x90 [i915] [<ffffffff8124a146>] local_pci_probe+0x46/0x80 [<ffffffff8124a9d1>] pci_device_probe+0x101/0x110 [<ffffffff81306f86>] driver_probe_device+0x76/0x240 [<ffffffff813071f3>] __driver_attach+0xa3/0xb0 [<ffffffff813051fd>] bus_for_each_dev+0x4d/0x90 [<ffffffff81306ae9>] driver_attach+0x19/0x20 [<ffffffff813066a0>] bus_add_driver+0x1a0/0x270 [<ffffffff81307882>] driver_register+0x72/0x170 [<ffffffff8124aacf>] __pci_register_driver+0x5f/0x70 [<ffffffff812ee435>] drm_pci_init+0x115/0x130 [<ffffffffa00ff066>] i915_init+0x66/0x68 [i915] [<ffffffff810002da>] do_one_initcall+0x11a/0x170 [<ffffffff8109cf84>] load_module+0xfd4/0x13c0 [<ffffffff8109d427>] sys_init_module+0xb7/0xe0 [<ffffffff8155af16>] system_call_fastpath+0x1a/0x1f other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock((fb_notifier_list).rwsem); lock(console_lock); lock((fb_notifier_list).rwsem); lock(console_lock); *** DEADLOCK *** 6 locks held by modprobe/603: #0: (&__lockdep_no_validate__){......}, at: [<ffffffff813071a3>] __driver_attach+0x53/0xb0 #1: (&__lockdep_no_validate__){......}, at: [<ffffffff813071b1>] __driver_attach+0x61/0xb0 #2: (drm_global_mutex){+.+.+.}, at: [<ffffffff812ee12c>] drm_get_pci_dev+0xbc/0x2b0 #3: (registration_lock){+.+.+.}, at: [<ffffffff81264d8b>] remove_conflicting_framebuffers+0x2b/0x60 #4: (&fb_info->lock){+.+.+.}, at: [<ffffffff81262ef1>] lock_fb_info+0x21/0x60 #5: ((fb_notifier_list).rwsem){++++.+}, at: [<ffffffff810697c1>] __blocking_notifier_call_chain+0x51/0xc0 stack backtrace: Pid: 603, comm: modprobe Not tainted 3.8.0-rc2-expert+ #2 Call Trace: [<ffffffff8154f886>] print_circular_bug+0x28e/0x29f [<ffffffff8108ff10>] validate_chain.isra.33+0x1000/0x10d0 [<ffffffff81090a61>] __lock_acquire+0x3a1/0xb60 [<ffffffff8155a12a>] ? _raw_spin_unlock_irqrestore+0x3a/0x70 [<ffffffff8109209d>] ? trace_hardirqs_on_caller+0x10d/0x1a0 [<ffffffff810916ea>] lock_acquire+0x5a/0x70 [<ffffffff812c869f>] ? unbind_con_driver+0x3f/0x200 [<ffffffff810407a7>] console_lock+0x77/0x80 [<ffffffff812c869f>] ? unbind_con_driver+0x3f/0x200 [<ffffffff812c869f>] unbind_con_driver+0x3f/0x200 [<ffffffff81090a61>] ? __lock_acquire+0x3a1/0xb60 [<ffffffff81272bc7>] fbcon_event_notify+0x447/0x8b0 [<ffffffff810693a5>] notifier_call_chain+0x55/0x110 [<ffffffff810697d7>] __blocking_notifier_call_chain+0x67/0xc0 [<ffffffff81069841>] blocking_notifier_call_chain+0x11/0x20 [<ffffffff81262a16>] fb_notifier_call_chain+0x16/0x20 [<ffffffff812647db>] do_unregister_framebuffer+0x5b/0x110 [<ffffffff81264a28>] do_remove_conflicting_framebuffers+0x158/0x190 [<ffffffff81264d9a>] remove_conflicting_framebuffers+0x3a/0x60 [<ffffffffa007dbe4>] i915_driver_load+0x7d4/0xe70 [i915] [<ffffffff812ee1ee>] drm_get_pci_dev+0x17e/0x2b0 [<ffffffff8109213d>] ? trace_hardirqs_on+0xd/0x10 [<ffffffffa0079616>] i915_pci_probe+0x36/0x90 [i915] [<ffffffff8124a146>] local_pci_probe+0x46/0x80 [<ffffffff8124a9d1>] pci_device_probe+0x101/0x110 [<ffffffff81306f86>] driver_probe_device+0x76/0x240 [<ffffffff813071f3>] __driver_attach+0xa3/0xb0 [<ffffffff81307150>] ? driver_probe_device+0x240/0x240 [<ffffffff813051fd>] bus_for_each_dev+0x4d/0x90 [<ffffffff81306ae9>] driver_attach+0x19/0x20 [<ffffffff813066a0>] bus_add_driver+0x1a0/0x270 [<ffffffffa00ff000>] ? 0xffffffffa00fefff [<ffffffff81307882>] driver_register+0x72/0x170 [<ffffffffa00ff000>] ? 0xffffffffa00fefff [<ffffffff8124aacf>] __pci_register_driver+0x5f/0x70 [<ffffffff812ee435>] drm_pci_init+0x115/0x130 [<ffffffffa00ff000>] ? 0xffffffffa00fefff [<ffffffffa00ff066>] i915_init+0x66/0x68 [i915] [<ffffffff810002da>] do_one_initcall+0x11a/0x170 [<ffffffff8109cf84>] load_module+0xfd4/0x13c0 [<ffffffff81098ab0>] ? in_lock_functions+0x20/0x20 [<ffffffff8109d427>] sys_init_module+0xb7/0xe0 [<ffffffff8155af16>] system_call_fastpath+0x1a/0x1f Console: switching to colour dummy device 80x25 -- Daniel J Blueman
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