drm/i915/lvds: Move acpi lid notification registration to registration phase

commit b9eb9c92899a509fe258d38dd6c214b1de69eee0 upstream.

Delay registering ourselves with the acpi lid notification mechanism
until we are registering the connectors after initialisation is
complete. This prevents a possibility of trying to handle the lid
notification before we are ready with the danger of chasing
uninitialised function pointers.

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
 IP:           (null)
 PGD 0 P4D 0
 Oops: 0010 [#1] PREEMPT SMP PTI
 Modules linked in: arc4(+) iwldvm(+) i915(+) mac80211 i2c_algo_bit coretemp mei_wdt iwlwifi drm_kms_helper kvm_intel wmi_bmof iTCO_wdt iTCO_vendor_support kvm snd_hda_codec_conexant snd_hda_codec_generic drm psmouse cfg80211 irqbypass input_leds pcspkr i2c_i801 snd_hda_intel snd_hda_codec thinkpad_acpi snd_hda_core mei_me lpc_ich snd_hwdep e1000e wmi nvram snd_pcm mei snd_timer shpchp ptp pps_core rfkill syscopyarea snd intel_agp sysfillrect intel_gtt soundcore sysimgblt battery led_class fb_sys_fops ac rtc_cmos agpgart evdev mac_hid acpi_cpufreq ip_tables x_tables ext4 crc32c_generic crc16 mbcache jbd2 fscrypto crypto_simd glue_helper cryptd aes_x86_64 xts algif_skcipher af_alg dm_crypt dm_mod sd_mod uas usb_storage serio_raw atkbd libps2 ahci libahci uhci_hcd libata scsi_mod ehci_pci
  ehci_hcd usbcore usb_common i8042 serio
 CPU: 1 PID: 378 Comm: systemd-logind Not tainted 4.16.8-1-ARCH #1
 Hardware name: LENOVO 7454CTO/7454CTO, BIOS 6DET72WW (3.22 ) 10/25/2012
 RIP: 0010:          (null)
 RSP: 0018:ffffaf4580c33a18 EFLAGS: 00010287
 RAX: 0000000000000000 RBX: ffff947533558000 RCX: 000000000000003e
 RDX: ffffffffc0aa80c0 RSI: ffffaf4580c33a3c RDI: ffff947534e4c000
 RBP: ffff947533558338 R08: ffff947534598930 R09: ffffffffc0a928b1
 R10: ffffd8f181d5fd40 R11: 0000000000000000 R12: ffffffffc0a928b1
 R13: ffff947533558368 R14: ffffffffc0a928a9 R15: ffff947534e4c000
 FS:  00007f3dc4ddb940(0000) GS:ffff947539280000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000000 CR3: 000000006e214000 CR4: 00000000000406e0
 Call Trace:
  ?  intel_modeset_setup_hw_state+0x385/0xf60 [i915]
  ? __intel_display_resume+0x1e/0xc0 [i915]
  ? intel_display_resume+0xcc/0x120 [i915]
  ? intel_lid_notify+0xbc/0xc0 [i915]
  ? notifier_call_chain+0x47/0x70
  ? blocking_notifier_call_chain+0x3e/0x60
  ? acpi_lid_notify_state+0x8f/0x1d0
  ? acpi_lid_update_state+0x49/0x70
  ? acpi_lid_input_open+0x60/0x90
  ? input_open_device+0x5d/0xa0
  ? evdev_open+0x1ba/0x1e0 [evdev]
  ? chrdev_open+0xa3/0x1b0
  ? cdev_put.part.0+0x20/0x20
  ? do_dentry_open+0x14c/0x300
  ? path_openat+0x30c/0x1240
  ? current_time+0x16/0x60
  ? do_filp_open+0x93/0x100
  ? __check_object_size+0xfb/0x180
  ? do_sys_open+0x186/0x210
  ? do_syscall_64+0x74/0x190
  ?  entry_SYSCALL_64_after_hwframe+0x3d/0xa2
 Code:  Bad RIP value.
 RIP:           (null) RSP: ffffaf4580c33a18
 CR2: 0000000000000000

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=106559
Fixes: c1c7af608920 ("drm/i915: force mode set at lid open time")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180518074840.16194-1-chris@chris-wilson.co.uk
Cc: stable@vger.kernel.org
(cherry picked from commit e578a570dc7c20475774d1ff993825e3bd7a7011)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 32 insertions, 11 deletions

diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index 240308f1b6dd..b898f010b189 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -565,6 +565,36 @@ exit:
 	return NOTIFY_OK;
 }
 
+static int
+intel_lvds_connector_register(struct drm_connector *connector)
+{
+	struct intel_lvds_connector *lvds = to_lvds_connector(connector);
+	int ret;
+
+	ret = intel_connector_register(connector);
+	if (ret)
+		return ret;
+
+	lvds->lid_notifier.notifier_call = intel_lid_notify;
+	if (acpi_lid_notifier_register(&lvds->lid_notifier)) {
+		DRM_DEBUG_KMS("lid notifier registration failed\n");
+		lvds->lid_notifier.notifier_call = NULL;
+	}
+
+	return 0;
+}
+
+static void
+intel_lvds_connector_unregister(struct drm_connector *connector)
+{
+	struct intel_lvds_connector *lvds = to_lvds_connector(connector);
+
+	if (lvds->lid_notifier.notifier_call)
+		acpi_lid_notifier_unregister(&lvds->lid_notifier);
+
+	intel_connector_unregister(connector);
+}
+
 /**
  * intel_lvds_destroy - unregister and free LVDS structures
  * @connector: connector to free
@@ -577,9 +607,6 @@ static void intel_lvds_destroy(struct drm_connector *connector)
 	struct intel_lvds_connector *lvds_connector =
 		to_lvds_connector(connector);
 
-	if (lvds_connector->lid_notifier.notifier_call)
-		acpi_lid_notifier_unregister(&lvds_connector->lid_notifier);
-
 	if (!IS_ERR_OR_NULL(lvds_connector->base.edid))
 		kfree(lvds_connector->base.edid);
 
@@ -600,8 +627,8 @@ static const struct drm_connector_funcs intel_lvds_connector_funcs = {
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.atomic_get_property = intel_digital_connector_atomic_get_property,
 	.atomic_set_property = intel_digital_connector_atomic_set_property,
-	.late_register = intel_connector_register,
-	.early_unregister = intel_connector_unregister,
+	.late_register = intel_lvds_connector_register,
+	.early_unregister = intel_lvds_connector_unregister,
 	.destroy = intel_lvds_destroy,
 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 	.atomic_duplicate_state = intel_digital_connector_duplicate_state,
@@ -1149,12 +1176,6 @@ out:
 
 	lvds_encoder->a3_power = lvds & LVDS_A3_POWER_MASK;
 
-	lvds_connector->lid_notifier.notifier_call = intel_lid_notify;
-	if (acpi_lid_notifier_register(&lvds_connector->lid_notifier)) {
-		DRM_DEBUG_KMS("lid notifier registration failed\n");
-		lvds_connector->lid_notifier.notifier_call = NULL;
-	}
-
 	return;
 
 failed: