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authorDaniel Vetter <daniel.vetter@ffwll.ch>2014-05-29 17:54:47 -0400
committerDave Airlie <airlied@redhat.com>2014-06-03 23:25:21 -0400
commit6e9f798d91c526982cca0026cd451e8fdbf18aaf (patch)
treeeb892fa869e44d0a4f1de46ce2cb262be6b64ebe
parent8291272ad234ff21628ce1af9043847f01f58734 (diff)
drm: Split connection_mutex out of mode_config.mutex (v3)
After the split-out of crtc locks from the big mode_config.mutex there's still two major areas it protects: - Various connector probe states, like connector->status, EDID properties, probed mode lists and similar information. - The links from connector->encoder and encoder->crtc and other modeset-relevant connector state (e.g. properties which control the panel fitter). The later is used by modeset operations. But they don't really care about the former since it's allowed to e.g. enable a disconnected VGA output or with a mode not in the probed list. Thus far this hasn't been a problem, but for the atomic modeset conversion Rob Clark needs to convert all modeset relevant locks into w/w locks. This is required because the order of acquisition is determined by how userspace supplies the atomic modeset data. This has run into troubles in the detect path since the i915 load detect code needs _both_ protections offered by the mode_config.mutex: It updates probe state and it needs to change the modeset configuration to enable the temporary load detect pipe. The big deal here is that for the probe/detect users of this lock a plain mutex fits best, but for atomic modesets we really want a w/w mutex. To fix this lets split out a new connection_mutex lock for the modeset relevant parts. For simplicity I've decided to only add one additional lock for all connector/encoder links and modeset configuration states. We have piles of different modeset objects in addition to those (like bridges or panels), so adding per-object locks would be much more effort. Also, we're guaranteed (at least for now) to do a full modeset if we need to acquire this lock. Which means that fine-grained locking is fairly irrelevant compared to the amount of time the full modeset will take. I've done a full audit, and there's just a few things that justify special focus: - Locking in drm_sysfs.c is almost completely absent. We should sprinkle mode_config.connection_mutex over this file a bit, but since it already lacks mode_config.mutex this patch wont make the situation any worse. This is material for a follow-up patch. - omap has a omap_framebuffer_flush function which walks the connector->encoder->crtc links and is called from many contexts. Some look like they don't acquire mode_config.mutex, so this is already racy. Again fixing this is material for a separate patch. - The radeon hot_plug function to retrain DP links looks at connector->dpms. Currently this happens without any locking, so is already racy. I think radeon_hotplug_work_func should gain mutex_lock/unlock calls for the mode_config.connection_mutex. - Same applies to i915's intel_dp_hot_plug. But again, this is already racy. - i915 load_detect code needs to acquire this lock. Which means the w/w dance due to Rob's work will be nicely contained to _just_ this function. I've added fixme comments everywhere where it looks suspicious but in the sysfs code. After a quick irc discussion with Dave Airlie it sounds like the lack of locking in there is due to sysfs cleanup fun at module unload. v1: original (only compile tested) v2: missing mutex_init(), etc (from Rob Clark) v3: i915 needs more care in the conversion: - Protect the edp pp logic with the connection_mutex. - Use connection_mutex in the backlight code due to get_pipe_from_connector. - Use drm_modeset_lock_all in suspend/resume paths. - Update lock checks in the overlay code. Cc: Alex Deucher <alexdeucher@gmail.com> Cc: Rob Clark <robdclark@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Rob Clark <robdclark@gmail.com>
-rw-r--r--drivers/gpu/drm/drm_crtc.c8
-rw-r--r--drivers/gpu/drm/drm_crtc_helper.c2
-rw-r--r--drivers/gpu/drm/drm_edid.c2
-rw-r--r--drivers/gpu/drm/drm_plane_helper.c7
-rw-r--r--drivers/gpu/drm/i915/i915_debugfs.c4
-rw-r--r--drivers/gpu/drm/i915/i915_drv.c6
-rw-r--r--drivers/gpu/drm/i915/intel_display.c16
-rw-r--r--drivers/gpu/drm/i915/intel_dp.c15
-rw-r--r--drivers/gpu/drm/i915/intel_opregion.c4
-rw-r--r--drivers/gpu/drm/i915/intel_overlay.c4
-rw-r--r--drivers/gpu/drm/i915/intel_panel.c8
-rw-r--r--drivers/gpu/drm/omapdrm/omap_fb.c1
-rw-r--r--drivers/gpu/drm/radeon/radeon_connectors.c1
-rw-r--r--include/drm/drm_crtc.h1
14 files changed, 54 insertions, 25 deletions
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 5b3e2920c376..f3b98d4b6f46 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -54,6 +54,8 @@ void drm_modeset_lock_all(struct drm_device *dev)
54 54
55 mutex_lock(&dev->mode_config.mutex); 55 mutex_lock(&dev->mode_config.mutex);
56 56
57 mutex_lock(&dev->mode_config.connection_mutex);
58
57 list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) 59 list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
58 mutex_lock_nest_lock(&crtc->mutex, &dev->mode_config.mutex); 60 mutex_lock_nest_lock(&crtc->mutex, &dev->mode_config.mutex);
59} 61}
@@ -72,6 +74,8 @@ void drm_modeset_unlock_all(struct drm_device *dev)
72 list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) 74 list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
73 mutex_unlock(&crtc->mutex); 75 mutex_unlock(&crtc->mutex);
74 76
77 mutex_unlock(&dev->mode_config.connection_mutex);
78
75 mutex_unlock(&dev->mode_config.mutex); 79 mutex_unlock(&dev->mode_config.mutex);
76} 80}
77EXPORT_SYMBOL(drm_modeset_unlock_all); 81EXPORT_SYMBOL(drm_modeset_unlock_all);
@@ -93,6 +97,7 @@ void drm_warn_on_modeset_not_all_locked(struct drm_device *dev)
93 list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) 97 list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
94 WARN_ON(!mutex_is_locked(&crtc->mutex)); 98 WARN_ON(!mutex_is_locked(&crtc->mutex));
95 99
100 WARN_ON(!mutex_is_locked(&dev->mode_config.connection_mutex));
96 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex)); 101 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
97} 102}
98EXPORT_SYMBOL(drm_warn_on_modeset_not_all_locked); 103EXPORT_SYMBOL(drm_warn_on_modeset_not_all_locked);
@@ -1793,6 +1798,7 @@ int drm_mode_getconnector(struct drm_device *dev, void *data,
1793 DRM_DEBUG_KMS("[CONNECTOR:%d:?]\n", out_resp->connector_id); 1798 DRM_DEBUG_KMS("[CONNECTOR:%d:?]\n", out_resp->connector_id);
1794 1799
1795 mutex_lock(&dev->mode_config.mutex); 1800 mutex_lock(&dev->mode_config.mutex);
1801 mutex_lock(&dev->mode_config.connection_mutex);
1796 1802
1797 connector = drm_connector_find(dev, out_resp->connector_id); 1803 connector = drm_connector_find(dev, out_resp->connector_id);
1798 if (!connector) { 1804 if (!connector) {
@@ -1891,6 +1897,7 @@ int drm_mode_getconnector(struct drm_device *dev, void *data,
1891 out_resp->count_encoders = encoders_count; 1897 out_resp->count_encoders = encoders_count;
1892 1898
1893out: 1899out:
1900 mutex_unlock(&dev->mode_config.connection_mutex);
1894 mutex_unlock(&dev->mode_config.mutex); 1901 mutex_unlock(&dev->mode_config.mutex);
1895 1902
1896 return ret; 1903 return ret;
@@ -4640,6 +4647,7 @@ EXPORT_SYMBOL(drm_format_vert_chroma_subsampling);
4640void drm_mode_config_init(struct drm_device *dev) 4647void drm_mode_config_init(struct drm_device *dev)
4641{ 4648{
4642 mutex_init(&dev->mode_config.mutex); 4649 mutex_init(&dev->mode_config.mutex);
4650 mutex_init(&dev->mode_config.connection_mutex);
4643 mutex_init(&dev->mode_config.idr_mutex); 4651 mutex_init(&dev->mode_config.idr_mutex);
4644 mutex_init(&dev->mode_config.fb_lock); 4652 mutex_init(&dev->mode_config.fb_lock);
4645 INIT_LIST_HEAD(&dev->mode_config.fb_list); 4653 INIT_LIST_HEAD(&dev->mode_config.fb_list);
diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c
index 231c9433341f..b55d27c872f6 100644
--- a/drivers/gpu/drm/drm_crtc_helper.c
+++ b/drivers/gpu/drm/drm_crtc_helper.c
@@ -89,6 +89,8 @@ bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
89 struct drm_device *dev = encoder->dev; 89 struct drm_device *dev = encoder->dev;
90 90
91 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex)); 91 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
92 WARN_ON(!mutex_is_locked(&dev->mode_config.connection_mutex));
93
92 list_for_each_entry(connector, &dev->mode_config.connector_list, head) 94 list_for_each_entry(connector, &dev->mode_config.connector_list, head)
93 if (connector->encoder == encoder) 95 if (connector->encoder == encoder)
94 return true; 96 return true;
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 085e5550aac5..7be21781d3bd 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -3304,6 +3304,8 @@ struct drm_connector *drm_select_eld(struct drm_encoder *encoder,
3304 struct drm_connector *connector; 3304 struct drm_connector *connector;
3305 struct drm_device *dev = encoder->dev; 3305 struct drm_device *dev = encoder->dev;
3306 3306
3307 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
3308
3307 list_for_each_entry(connector, &dev->mode_config.connector_list, head) 3309 list_for_each_entry(connector, &dev->mode_config.connector_list, head)
3308 if (connector->encoder == encoder && connector->eld[0]) 3310 if (connector->encoder == encoder && connector->eld[0])
3309 return connector; 3311 return connector;
diff --git a/drivers/gpu/drm/drm_plane_helper.c b/drivers/gpu/drm/drm_plane_helper.c
index d966afa7ecae..458d9bf09209 100644
--- a/drivers/gpu/drm/drm_plane_helper.c
+++ b/drivers/gpu/drm/drm_plane_helper.c
@@ -54,6 +54,13 @@ static int get_connectors_for_crtc(struct drm_crtc *crtc,
54 struct drm_connector *connector; 54 struct drm_connector *connector;
55 int count = 0; 55 int count = 0;
56 56
57 /*
58 * Note: Once we change the plane hooks to more fine-grained locking we
59 * need to grab the connection_mutex here to be able to make these
60 * checks.
61 */
62 WARN_ON(!mutex_is_locked(&dev->mode_config.connection_mutex));
63
57 list_for_each_entry(connector, &dev->mode_config.connector_list, head) 64 list_for_each_entry(connector, &dev->mode_config.connector_list, head)
58 if (connector->encoder && connector->encoder->crtc == crtc) { 65 if (connector->encoder && connector->encoder->crtc == crtc) {
59 if (connector_list != NULL && count < num_connectors) 66 if (connector_list != NULL && count < num_connectors)
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 36f4c15f538b..169fc2d8c554 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -2609,7 +2609,7 @@ static int i9xx_pipe_crc_auto_source(struct drm_device *dev, enum pipe pipe,
2609 2609
2610 *source = INTEL_PIPE_CRC_SOURCE_PIPE; 2610 *source = INTEL_PIPE_CRC_SOURCE_PIPE;
2611 2611
2612 mutex_lock(&dev->mode_config.mutex); 2612 drm_modeset_lock_all(dev);
2613 list_for_each_entry(encoder, &dev->mode_config.encoder_list, 2613 list_for_each_entry(encoder, &dev->mode_config.encoder_list,
2614 base.head) { 2614 base.head) {
2615 if (!encoder->base.crtc) 2615 if (!encoder->base.crtc)
@@ -2645,7 +2645,7 @@ static int i9xx_pipe_crc_auto_source(struct drm_device *dev, enum pipe pipe,
2645 break; 2645 break;
2646 } 2646 }
2647 } 2647 }
2648 mutex_unlock(&dev->mode_config.mutex); 2648 drm_modeset_unlock_all(dev);
2649 2649
2650 return ret; 2650 return ret;
2651} 2651}
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 4619c9e51907..5b5b82c3f570 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -533,13 +533,11 @@ static int i915_drm_freeze(struct drm_device *dev)
533 * Disable CRTCs directly since we want to preserve sw state 533 * Disable CRTCs directly since we want to preserve sw state
534 * for _thaw. 534 * for _thaw.
535 */ 535 */
536 mutex_lock(&dev->mode_config.mutex); 536 drm_modeset_lock_all(dev);
537 for_each_crtc(dev, crtc) { 537 for_each_crtc(dev, crtc) {
538 mutex_lock(&crtc->mutex);
539 dev_priv->display.crtc_disable(crtc); 538 dev_priv->display.crtc_disable(crtc);
540 mutex_unlock(&crtc->mutex);
541 } 539 }
542 mutex_unlock(&dev->mode_config.mutex); 540 drm_modeset_unlock_all(dev);
543 541
544 intel_modeset_suspend_hw(dev); 542 intel_modeset_suspend_hw(dev);
545 } 543 }
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index e80b2917e3cb..c2976ade823f 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -8323,6 +8323,8 @@ bool intel_get_load_detect_pipe(struct drm_connector *connector,
8323 connector->base.id, connector->name, 8323 connector->base.id, connector->name,
8324 encoder->base.id, encoder->name); 8324 encoder->base.id, encoder->name);
8325 8325
8326 mutex_lock(&dev->mode_config.connection_mutex);
8327
8326 /* 8328 /*
8327 * Algorithm gets a little messy: 8329 * Algorithm gets a little messy:
8328 * 8330 *
@@ -8365,7 +8367,7 @@ bool intel_get_load_detect_pipe(struct drm_connector *connector,
8365 */ 8367 */
8366 if (!crtc) { 8368 if (!crtc) {
8367 DRM_DEBUG_KMS("no pipe available for load-detect\n"); 8369 DRM_DEBUG_KMS("no pipe available for load-detect\n");
8368 return false; 8370 goto fail_unlock_connector;
8369 } 8371 }
8370 8372
8371 mutex_lock(&crtc->mutex); 8373 mutex_lock(&crtc->mutex);
@@ -8419,6 +8421,9 @@ bool intel_get_load_detect_pipe(struct drm_connector *connector,
8419 else 8421 else
8420 intel_crtc->new_config = NULL; 8422 intel_crtc->new_config = NULL;
8421 mutex_unlock(&crtc->mutex); 8423 mutex_unlock(&crtc->mutex);
8424fail_unlock_connector:
8425 mutex_unlock(&dev->mode_config.connection_mutex);
8426
8422 return false; 8427 return false;
8423} 8428}
8424 8429
@@ -8448,6 +8453,7 @@ void intel_release_load_detect_pipe(struct drm_connector *connector,
8448 } 8453 }
8449 8454
8450 mutex_unlock(&crtc->mutex); 8455 mutex_unlock(&crtc->mutex);
8456 mutex_unlock(&connector->dev->mode_config.connection_mutex);
8451 return; 8457 return;
8452 } 8458 }
8453 8459
@@ -8456,6 +8462,7 @@ void intel_release_load_detect_pipe(struct drm_connector *connector,
8456 connector->funcs->dpms(connector, old->dpms_mode); 8462 connector->funcs->dpms(connector, old->dpms_mode);
8457 8463
8458 mutex_unlock(&crtc->mutex); 8464 mutex_unlock(&crtc->mutex);
8465 mutex_unlock(&connector->dev->mode_config.connection_mutex);
8459} 8466}
8460 8467
8461static int i9xx_pll_refclk(struct drm_device *dev, 8468static int i9xx_pll_refclk(struct drm_device *dev,
@@ -10986,8 +10993,9 @@ static void intel_crtc_init(struct drm_device *dev, int pipe)
10986enum pipe intel_get_pipe_from_connector(struct intel_connector *connector) 10993enum pipe intel_get_pipe_from_connector(struct intel_connector *connector)
10987{ 10994{
10988 struct drm_encoder *encoder = connector->base.encoder; 10995 struct drm_encoder *encoder = connector->base.encoder;
10996 struct drm_device *dev = connector->base.dev;
10989 10997
10990 WARN_ON(!mutex_is_locked(&connector->base.dev->mode_config.mutex)); 10998 WARN_ON(!mutex_is_locked(&dev->mode_config.connection_mutex));
10991 10999
10992 if (!encoder) 11000 if (!encoder)
10993 return INVALID_PIPE; 11001 return INVALID_PIPE;
@@ -11756,9 +11764,9 @@ void intel_modeset_init(struct drm_device *dev)
11756 /* Just in case the BIOS is doing something questionable. */ 11764 /* Just in case the BIOS is doing something questionable. */
11757 intel_disable_fbc(dev); 11765 intel_disable_fbc(dev);
11758 11766
11759 mutex_lock(&dev->mode_config.mutex); 11767 drm_modeset_lock_all(dev);
11760 intel_modeset_setup_hw_state(dev, false); 11768 intel_modeset_setup_hw_state(dev, false);
11761 mutex_unlock(&dev->mode_config.mutex); 11769 drm_modeset_unlock_all(dev);
11762 11770
11763 for_each_intel_crtc(dev, crtc) { 11771 for_each_intel_crtc(dev, crtc) {
11764 if (!crtc->active) 11772 if (!crtc->active)
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index d94f0271e422..c4d883921282 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1154,7 +1154,7 @@ static void edp_panel_vdd_off_sync(struct intel_dp *intel_dp)
1154 u32 pp; 1154 u32 pp;
1155 u32 pp_stat_reg, pp_ctrl_reg; 1155 u32 pp_stat_reg, pp_ctrl_reg;
1156 1156
1157 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex)); 1157 WARN_ON(!mutex_is_locked(&dev->mode_config.connection_mutex));
1158 1158
1159 if (!intel_dp->want_panel_vdd && edp_have_panel_vdd(intel_dp)) { 1159 if (!intel_dp->want_panel_vdd && edp_have_panel_vdd(intel_dp)) {
1160 struct intel_digital_port *intel_dig_port = 1160 struct intel_digital_port *intel_dig_port =
@@ -1191,9 +1191,9 @@ static void edp_panel_vdd_work(struct work_struct *__work)
1191 struct intel_dp, panel_vdd_work); 1191 struct intel_dp, panel_vdd_work);
1192 struct drm_device *dev = intel_dp_to_dev(intel_dp); 1192 struct drm_device *dev = intel_dp_to_dev(intel_dp);
1193 1193
1194 mutex_lock(&dev->mode_config.mutex); 1194 mutex_lock(&dev->mode_config.connection_mutex);
1195 edp_panel_vdd_off_sync(intel_dp); 1195 edp_panel_vdd_off_sync(intel_dp);
1196 mutex_unlock(&dev->mode_config.mutex); 1196 mutex_unlock(&dev->mode_config.connection_mutex);
1197} 1197}
1198 1198
1199static void edp_panel_vdd_off(struct intel_dp *intel_dp, bool sync) 1199static void edp_panel_vdd_off(struct intel_dp *intel_dp, bool sync)
@@ -3235,6 +3235,7 @@ intel_dp_check_link_status(struct intel_dp *intel_dp)
3235 u8 sink_irq_vector; 3235 u8 sink_irq_vector;
3236 u8 link_status[DP_LINK_STATUS_SIZE]; 3236 u8 link_status[DP_LINK_STATUS_SIZE];
3237 3237
3238 /* FIXME: This access isn't protected by any locks. */
3238 if (!intel_encoder->connectors_active) 3239 if (!intel_encoder->connectors_active)
3239 return; 3240 return;
3240 3241
@@ -3665,9 +3666,9 @@ void intel_dp_encoder_destroy(struct drm_encoder *encoder)
3665 drm_encoder_cleanup(encoder); 3666 drm_encoder_cleanup(encoder);
3666 if (is_edp(intel_dp)) { 3667 if (is_edp(intel_dp)) {
3667 cancel_delayed_work_sync(&intel_dp->panel_vdd_work); 3668 cancel_delayed_work_sync(&intel_dp->panel_vdd_work);
3668 mutex_lock(&dev->mode_config.mutex); 3669 mutex_lock(&dev->mode_config.connection_mutex);
3669 edp_panel_vdd_off_sync(intel_dp); 3670 edp_panel_vdd_off_sync(intel_dp);
3670 mutex_unlock(&dev->mode_config.mutex); 3671 mutex_unlock(&dev->mode_config.connection_mutex);
3671 } 3672 }
3672 kfree(intel_dig_port); 3673 kfree(intel_dig_port);
3673} 3674}
@@ -4246,9 +4247,9 @@ intel_dp_init_connector(struct intel_digital_port *intel_dig_port,
4246 drm_dp_aux_unregister_i2c_bus(&intel_dp->aux); 4247 drm_dp_aux_unregister_i2c_bus(&intel_dp->aux);
4247 if (is_edp(intel_dp)) { 4248 if (is_edp(intel_dp)) {
4248 cancel_delayed_work_sync(&intel_dp->panel_vdd_work); 4249 cancel_delayed_work_sync(&intel_dp->panel_vdd_work);
4249 mutex_lock(&dev->mode_config.mutex); 4250 mutex_lock(&dev->mode_config.connection_mutex);
4250 edp_panel_vdd_off_sync(intel_dp); 4251 edp_panel_vdd_off_sync(intel_dp);
4251 mutex_unlock(&dev->mode_config.mutex); 4252 mutex_unlock(&dev->mode_config.connection_mutex);
4252 } 4253 }
4253 drm_sysfs_connector_remove(connector); 4254 drm_sysfs_connector_remove(connector);
4254 drm_connector_cleanup(connector); 4255 drm_connector_cleanup(connector);
diff --git a/drivers/gpu/drm/i915/intel_opregion.c b/drivers/gpu/drm/i915/intel_opregion.c
index acde2945eb8a..b812e9d39f38 100644
--- a/drivers/gpu/drm/i915/intel_opregion.c
+++ b/drivers/gpu/drm/i915/intel_opregion.c
@@ -410,7 +410,7 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
410 if (bclp > 255) 410 if (bclp > 255)
411 return ASLC_BACKLIGHT_FAILED; 411 return ASLC_BACKLIGHT_FAILED;
412 412
413 mutex_lock(&dev->mode_config.mutex); 413 mutex_lock(&dev->mode_config.connection_mutex);
414 414
415 /* 415 /*
416 * Update backlight on all connectors that support backlight (usually 416 * Update backlight on all connectors that support backlight (usually
@@ -421,7 +421,7 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
421 intel_panel_set_backlight(intel_connector, bclp, 255); 421 intel_panel_set_backlight(intel_connector, bclp, 255);
422 iowrite32(DIV_ROUND_UP(bclp * 100, 255) | ASLE_CBLV_VALID, &asle->cblv); 422 iowrite32(DIV_ROUND_UP(bclp * 100, 255) | ASLE_CBLV_VALID, &asle->cblv);
423 423
424 mutex_unlock(&dev->mode_config.mutex); 424 mutex_unlock(&dev->mode_config.connection_mutex);
425 425
426 426
427 return 0; 427 return 0;
diff --git a/drivers/gpu/drm/i915/intel_overlay.c b/drivers/gpu/drm/i915/intel_overlay.c
index 27eb820d1b19..e97ea33e0117 100644
--- a/drivers/gpu/drm/i915/intel_overlay.c
+++ b/drivers/gpu/drm/i915/intel_overlay.c
@@ -688,7 +688,7 @@ static int intel_overlay_do_put_image(struct intel_overlay *overlay,
688 u32 swidth, swidthsw, sheight, ostride; 688 u32 swidth, swidthsw, sheight, ostride;
689 689
690 BUG_ON(!mutex_is_locked(&dev->struct_mutex)); 690 BUG_ON(!mutex_is_locked(&dev->struct_mutex));
691 BUG_ON(!mutex_is_locked(&dev->mode_config.mutex)); 691 BUG_ON(!mutex_is_locked(&dev->mode_config.connection_mutex));
692 BUG_ON(!overlay); 692 BUG_ON(!overlay);
693 693
694 ret = intel_overlay_release_old_vid(overlay); 694 ret = intel_overlay_release_old_vid(overlay);
@@ -793,7 +793,7 @@ int intel_overlay_switch_off(struct intel_overlay *overlay)
793 int ret; 793 int ret;
794 794
795 BUG_ON(!mutex_is_locked(&dev->struct_mutex)); 795 BUG_ON(!mutex_is_locked(&dev->struct_mutex));
796 BUG_ON(!mutex_is_locked(&dev->mode_config.mutex)); 796 BUG_ON(!mutex_is_locked(&dev->mode_config.connection_mutex));
797 797
798 ret = intel_overlay_recover_from_interrupt(overlay); 798 ret = intel_overlay_recover_from_interrupt(overlay);
799 if (ret != 0) 799 if (ret != 0)
diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 3fb3f939dca5..d4d415665475 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -876,12 +876,12 @@ static int intel_backlight_device_update_status(struct backlight_device *bd)
876 struct intel_connector *connector = bl_get_data(bd); 876 struct intel_connector *connector = bl_get_data(bd);
877 struct drm_device *dev = connector->base.dev; 877 struct drm_device *dev = connector->base.dev;
878 878
879 mutex_lock(&dev->mode_config.mutex); 879 mutex_lock(&dev->mode_config.connection_mutex);
880 DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n", 880 DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n",
881 bd->props.brightness, bd->props.max_brightness); 881 bd->props.brightness, bd->props.max_brightness);
882 intel_panel_set_backlight(connector, bd->props.brightness, 882 intel_panel_set_backlight(connector, bd->props.brightness,
883 bd->props.max_brightness); 883 bd->props.max_brightness);
884 mutex_unlock(&dev->mode_config.mutex); 884 mutex_unlock(&dev->mode_config.connection_mutex);
885 return 0; 885 return 0;
886} 886}
887 887
@@ -893,9 +893,9 @@ static int intel_backlight_device_get_brightness(struct backlight_device *bd)
893 int ret; 893 int ret;
894 894
895 intel_runtime_pm_get(dev_priv); 895 intel_runtime_pm_get(dev_priv);
896 mutex_lock(&dev->mode_config.mutex); 896 mutex_lock(&dev->mode_config.connection_mutex);
897 ret = intel_panel_get_backlight(connector); 897 ret = intel_panel_get_backlight(connector);
898 mutex_unlock(&dev->mode_config.mutex); 898 mutex_unlock(&dev->mode_config.connection_mutex);
899 intel_runtime_pm_put(dev_priv); 899 intel_runtime_pm_put(dev_priv);
900 900
901 return ret; 901 return ret;
diff --git a/drivers/gpu/drm/omapdrm/omap_fb.c b/drivers/gpu/drm/omapdrm/omap_fb.c
index 8b019602ffe6..2a5cacdc344b 100644
--- a/drivers/gpu/drm/omapdrm/omap_fb.c
+++ b/drivers/gpu/drm/omapdrm/omap_fb.c
@@ -346,6 +346,7 @@ void omap_framebuffer_flush(struct drm_framebuffer *fb,
346 346
347 VERB("flush: %d,%d %dx%d, fb=%p", x, y, w, h, fb); 347 VERB("flush: %d,%d %dx%d, fb=%p", x, y, w, h, fb);
348 348
349 /* FIXME: This is racy - no protection against modeset config changes. */
349 while ((connector = omap_framebuffer_get_next_connector(fb, connector))) { 350 while ((connector = omap_framebuffer_get_next_connector(fb, connector))) {
350 /* only consider connectors that are part of a chain */ 351 /* only consider connectors that are part of a chain */
351 if (connector->encoder && connector->encoder->crtc) { 352 if (connector->encoder && connector->encoder->crtc) {
diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c b/drivers/gpu/drm/radeon/radeon_connectors.c
index 31d4cf60bae3..4522f7dce653 100644
--- a/drivers/gpu/drm/radeon/radeon_connectors.c
+++ b/drivers/gpu/drm/radeon/radeon_connectors.c
@@ -48,6 +48,7 @@ void radeon_connector_hotplug(struct drm_connector *connector)
48 radeon_hpd_set_polarity(rdev, radeon_connector->hpd.hpd); 48 radeon_hpd_set_polarity(rdev, radeon_connector->hpd.hpd);
49 49
50 /* if the connector is already off, don't turn it back on */ 50 /* if the connector is already off, don't turn it back on */
51 /* FIXME: This access isn't protected by any locks. */
51 if (connector->dpms != DRM_MODE_DPMS_ON) 52 if (connector->dpms != DRM_MODE_DPMS_ON)
52 return; 53 return;
53 54
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 849cfdccff09..6c295df7b0df 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -738,6 +738,7 @@ struct drm_mode_group {
738 */ 738 */
739struct drm_mode_config { 739struct drm_mode_config {
740 struct mutex mutex; /* protects configuration (mode lists etc.) */ 740 struct mutex mutex; /* protects configuration (mode lists etc.) */
741 struct mutex connection_mutex; /* protects connector->encoder and encoder->crtc links */
741 struct mutex idr_mutex; /* for IDR management */ 742 struct mutex idr_mutex; /* for IDR management */
742 struct idr crtc_idr; /* use this idr for all IDs, fb, crtc, connector, modes - just makes life easier */ 743 struct idr crtc_idr; /* use this idr for all IDs, fb, crtc, connector, modes - just makes life easier */
743 /* this is limited to one for now */ 744 /* this is limited to one for now */