From 4d4c2d89913e2d891bd6a34b12050a2576e60525 Mon Sep 17 00:00:00 2001 From: Noralf Trønnes Date: Mon, 1 Oct 2018 21:45:36 +0200 Subject: drm/cma-helper: Fix crash in fbdev error path MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sergey Suloev reported a crash happening in drm_client_dev_hotplug() when fbdev had failed to register. [ 9.124598] vc4_hdmi 3f902000.hdmi: ASoC: Failed to create component debugfs directory [ 9.147667] vc4_hdmi 3f902000.hdmi: vc4-hdmi-hifi <-> 3f902000.hdmi mapping ok [ 9.155184] vc4_hdmi 3f902000.hdmi: ASoC: no DMI vendor name! [ 9.166544] vc4-drm soc:gpu: bound 3f902000.hdmi (ops vc4_hdmi_ops [vc4]) [ 9.173840] vc4-drm soc:gpu: bound 3f806000.vec (ops vc4_vec_ops [vc4]) [ 9.181029] vc4-drm soc:gpu: bound 3f004000.txp (ops vc4_txp_ops [vc4]) [ 9.188519] vc4-drm soc:gpu: bound 3f400000.hvs (ops vc4_hvs_ops [vc4]) [ 9.195690] vc4-drm soc:gpu: bound 3f206000.pixelvalve (ops vc4_crtc_ops [vc4]) [ 9.203523] vc4-drm soc:gpu: bound 3f207000.pixelvalve (ops vc4_crtc_ops [vc4]) [ 9.215032] vc4-drm soc:gpu: bound 3f807000.pixelvalve (ops vc4_crtc_ops [vc4]) [ 9.274785] vc4-drm soc:gpu: bound 3fc00000.v3d (ops vc4_v3d_ops [vc4]) [ 9.290246] [drm] Initialized vc4 0.0.0 20140616 for soc:gpu on minor 0 [ 9.297464] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013). [ 9.304600] [drm] Driver supports precise vblank timestamp query. [ 9.382856] vc4-drm soc:gpu: [drm:drm_fb_helper_fbdev_setup [drm_kms_helper]] *ERROR* Failed to set fbdev configuration [ 10.404937] Unable to handle kernel paging request at virtual address 00330a656369768a [ 10.441620] [00330a656369768a] address between user and kernel address ranges [ 10.449087] Internal error: Oops: 96000004 [#1] PREEMPT SMP [ 10.454762] Modules linked in: brcmfmac vc4 drm_kms_helper cfg80211 drm rfkill smsc95xx brcmutil usbnet drm_panel_orientation_quirks raspberrypi_hwmon bcm2835_dma crc32_ce pwm_bcm2835 bcm2835_rng virt_dma rng_core i2c_bcm2835 ip_tables x_tables ipv6 [ 10.477296] CPU: 2 PID: 45 Comm: kworker/2:1 Not tainted 4.19.0-rc5 #3 [ 10.483934] Hardware name: Raspberry Pi 3 Model B Rev 1.2 (DT) [ 10.489966] Workqueue: events output_poll_execute [drm_kms_helper] [ 10.596515] Process kworker/2:1 (pid: 45, stack limit = 0x000000007e8924dc) [ 10.603590] Call trace: [ 10.606259] drm_client_dev_hotplug+0x5c/0xb0 [drm] [ 10.611303] drm_kms_helper_hotplug_event+0x30/0x40 [drm_kms_helper] [ 10.617849] output_poll_execute+0xc4/0x1e0 [drm_kms_helper] [ 10.623616] process_one_work+0x1c8/0x318 [ 10.627695] worker_thread+0x48/0x428 [ 10.631420] kthread+0xf8/0x128 [ 10.634615] ret_from_fork+0x10/0x18 [ 10.638255] Code: 54000220 f9401261 aa1303e0 b4000141 (f9400c21) [ 10.644456] ---[ end trace c75b4a4b0e141908 ]--- The reason for this is that drm_fbdev_cma_init() removes the drm_client when fbdev registration fails, but it doesn't remove the client from the drm_device client list. So the client list now has a pointer that points into the unknown and we have a 'use after free' situation. Split drm_client_new() into drm_client_init() and drm_client_add() to fix removal in the error path. Fixes: 894a677f4b3e ("drm/cma-helper: Use the generic fbdev emulation") Reported-by: Sergey Suloev Cc: Stefan Wahren Cc: Eric Anholt Cc: Daniel Vetter Signed-off-by: Noralf Trønnes Reviewed-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20181001194536.57756-1-noralf@tronnes.org --- include/drm/drm_client.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include/drm') diff --git a/include/drm/drm_client.h b/include/drm/drm_client.h index 989f8e52864d..971bb7853776 100644 --- a/include/drm/drm_client.h +++ b/include/drm/drm_client.h @@ -87,9 +87,10 @@ struct drm_client_dev { struct drm_file *file; }; -int drm_client_new(struct drm_device *dev, struct drm_client_dev *client, - const char *name, const struct drm_client_funcs *funcs); +int drm_client_init(struct drm_device *dev, struct drm_client_dev *client, + const char *name, const struct drm_client_funcs *funcs); void drm_client_release(struct drm_client_dev *client); +void drm_client_add(struct drm_client_dev *client); void drm_client_dev_unregister(struct drm_device *dev); void drm_client_dev_hotplug(struct drm_device *dev); -- cgit v1.2.3 From 9068e02f58740778d8270840657f1e250a2cc60f Mon Sep 17 00:00:00 2001 From: Clint Taylor Date: Fri, 5 Oct 2018 14:52:15 -0700 Subject: drm/edid: VSDB yCBCr420 Deep Color mode bit definitions HDMI Forum VSDB YCBCR420 deep color capability bits are 2:0. Correct definitions in the header for the mask to work correctly. Fixes: e6a9a2c3dc43 ("drm/edid: parse ycbcr 420 deep color information") Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107893 Cc: # v4.14+ Signed-off-by: Clint Taylor Reviewed-by: Jani Nikula Reviewed-by: Shashank Sharma Signed-off-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/1538776335-12569-1-git-send-email-clinton.a.taylor@intel.com --- drivers/gpu/drm/drm_edid.c | 2 +- include/drm/drm_edid.h | 6 +++--- 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'include/drm') diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 1e2b9407c8d0..ff0bfc65a8c1 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -4282,7 +4282,7 @@ static void drm_parse_ycbcr420_deep_color_info(struct drm_connector *connector, struct drm_hdmi_info *hdmi = &connector->display_info.hdmi; dc_mask = db[7] & DRM_EDID_YCBCR420_DC_MASK; - hdmi->y420_dc_modes |= dc_mask; + hdmi->y420_dc_modes = dc_mask; } static void drm_parse_hdmi_forum_vsdb(struct drm_connector *connector, diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h index b25d12ef120a..e3c404833115 100644 --- a/include/drm/drm_edid.h +++ b/include/drm/drm_edid.h @@ -214,9 +214,9 @@ struct detailed_timing { #define DRM_EDID_HDMI_DC_Y444 (1 << 3) /* YCBCR 420 deep color modes */ -#define DRM_EDID_YCBCR420_DC_48 (1 << 6) -#define DRM_EDID_YCBCR420_DC_36 (1 << 5) -#define DRM_EDID_YCBCR420_DC_30 (1 << 4) +#define DRM_EDID_YCBCR420_DC_48 (1 << 2) +#define DRM_EDID_YCBCR420_DC_36 (1 << 1) +#define DRM_EDID_YCBCR420_DC_30 (1 << 0) #define DRM_EDID_YCBCR420_DC_MASK (DRM_EDID_YCBCR420_DC_48 | \ DRM_EDID_YCBCR420_DC_36 | \ DRM_EDID_YCBCR420_DC_30) -- cgit v1.2.3 From 4364bcb2cd21d042bde4776448417ddffbc54045 Mon Sep 17 00:00:00 2001 From: Leo Li Date: Mon, 15 Oct 2018 09:46:40 -0400 Subject: drm: Get ref on CRTC commit object when waiting for flip_done This fixes a general protection fault, caused by accessing the contents of a flip_done completion object that has already been freed. It occurs due to the preemption of a non-blocking commit worker thread W by another commit thread X. X continues to clear its atomic state at the end, destroying the CRTC commit object that W still needs. Switching back to W and accessing the commit objects then leads to bad results. Worker W becomes preemptable when waiting for flip_done to complete. At this point, a frequently occurring commit thread X can take over. Here's an example where W is a worker thread that flips on both CRTCs, and X does a legacy cursor update on both CRTCs: ... 1. W does flip work 2. W runs commit_hw_done() 3. W waits for flip_done on CRTC 1 4. > flip_done for CRTC 1 completes 5. W finishes waiting for CRTC 1 6. W waits for flip_done on CRTC 2 7. > Preempted by X 8. > flip_done for CRTC 2 completes 9. X atomic_check: hw_done and flip_done are complete on all CRTCs 10. X updates cursor on both CRTCs 11. X destroys atomic state 12. X done 13. > Switch back to W 14. W waits for flip_done on CRTC 2 15. W raises general protection fault The error looks like so: general protection fault: 0000 [#1] PREEMPT SMP PTI **snip** Call Trace: lock_acquire+0xa2/0x1b0 _raw_spin_lock_irq+0x39/0x70 wait_for_completion_timeout+0x31/0x130 drm_atomic_helper_wait_for_flip_done+0x64/0x90 [drm_kms_helper] amdgpu_dm_atomic_commit_tail+0xcae/0xdd0 [amdgpu] commit_tail+0x3d/0x70 [drm_kms_helper] process_one_work+0x212/0x650 worker_thread+0x49/0x420 kthread+0xfb/0x130 ret_from_fork+0x3a/0x50 Modules linked in: x86_pkg_temp_thermal amdgpu(O) chash(O) gpu_sched(O) drm_kms_helper(O) syscopyarea sysfillrect sysimgblt fb_sys_fops ttm(O) drm(O) Note that i915 has this issue masked, since hw_done is signaled after waiting for flip_done. Doing so will block the cursor update from happening until hw_done is signaled, preventing the cursor commit from destroying the state. v2: The reference on the commit object needs to be obtained before hw_done() is signaled, since that's the point where another commit is allowed to modify the state. Assuming that the new_crtc_state->commit object still exists within flip_done() is incorrect. Fix by getting a reference in setup_commit(), and releasing it during default_clear(). Signed-off-by: Leo Li Reviewed-by: Daniel Vetter Signed-off-by: Harry Wentland Link: https://patchwork.freedesktop.org/patch/msgid/1539611200-6184-1-git-send-email-sunpeng.li@amd.com --- drivers/gpu/drm/drm_atomic.c | 5 +++++ drivers/gpu/drm/drm_atomic_helper.c | 12 ++++++++---- include/drm/drm_atomic.h | 11 +++++++++++ 3 files changed, 24 insertions(+), 4 deletions(-) (limited to 'include/drm') diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c index 018fcdb353d2..281cf9cbb44c 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -174,6 +174,11 @@ void drm_atomic_state_default_clear(struct drm_atomic_state *state) state->crtcs[i].state = NULL; state->crtcs[i].old_state = NULL; state->crtcs[i].new_state = NULL; + + if (state->crtcs[i].commit) { + drm_crtc_commit_put(state->crtcs[i].commit); + state->crtcs[i].commit = NULL; + } } for (i = 0; i < config->num_total_plane; i++) { diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index 80be74df7ba6..1bb4c318bdd4 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -1408,15 +1408,16 @@ EXPORT_SYMBOL(drm_atomic_helper_wait_for_vblanks); void drm_atomic_helper_wait_for_flip_done(struct drm_device *dev, struct drm_atomic_state *old_state) { - struct drm_crtc_state *new_crtc_state; struct drm_crtc *crtc; int i; - for_each_new_crtc_in_state(old_state, crtc, new_crtc_state, i) { - struct drm_crtc_commit *commit = new_crtc_state->commit; + for (i = 0; i < dev->mode_config.num_crtc; i++) { + struct drm_crtc_commit *commit = old_state->crtcs[i].commit; int ret; - if (!commit) + crtc = old_state->crtcs[i].ptr; + + if (!crtc || !commit) continue; ret = wait_for_completion_timeout(&commit->flip_done, 10 * HZ); @@ -1934,6 +1935,9 @@ int drm_atomic_helper_setup_commit(struct drm_atomic_state *state, drm_crtc_commit_get(commit); commit->abort_completion = true; + + state->crtcs[i].commit = commit; + drm_crtc_commit_get(commit); } for_each_oldnew_connector_in_state(state, conn, old_conn_state, new_conn_state, i) { diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h index da9d95a19580..1e713154f00e 100644 --- a/include/drm/drm_atomic.h +++ b/include/drm/drm_atomic.h @@ -153,6 +153,17 @@ struct __drm_planes_state { struct __drm_crtcs_state { struct drm_crtc *ptr; struct drm_crtc_state *state, *old_state, *new_state; + + /** + * @commit: + * + * A reference to the CRTC commit object that is kept for use by + * drm_atomic_helper_wait_for_flip_done() after + * drm_atomic_helper_commit_hw_done() is called. This ensures that a + * concurrent commit won't free a commit object that is still in use. + */ + struct drm_crtc_commit *commit; + s32 __user *out_fence_ptr; u64 last_vblank_count; }; -- cgit v1.2.3 From de9f8eea5a44b0b756d3d6345af7f8e630a3c8c0 Mon Sep 17 00:00:00 2001 From: Lyude Paul Date: Tue, 16 Oct 2018 16:39:46 -0400 Subject: drm/atomic_helper: Stop modesets on unregistered connectors harder MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Unfortunately, it appears our fix in: commit b5d29843d8ef ("drm/atomic_helper: Allow DPMS On<->Off changes for unregistered connectors") Which attempted to work around the problems introduced by: commit 4d80273976bf ("drm/atomic_helper: Disallow new modesets on unregistered connectors") Is still not the right solution, as modesets can still be triggered outside of drm_atomic_set_crtc_for_connector(). So in order to fix this, while still being careful that we don't break modesets that a driver may perform before being registered with userspace, we replace connector->registered with a tristate member, connector->registration_state. This allows us to keep track of whether or not a connector is still initializing and hasn't been exposed to userspace, is currently registered and exposed to userspace, or has been legitimately removed from the system after having once been present. Using this info, we can prevent userspace from performing new modesets on unregistered connectors while still allowing the driver to perform modesets on unregistered connectors before the driver has finished being registered. Changes since v1: - Fix WARN_ON() in drm_connector_cleanup() that CI caught with this patchset in igt@drv_module_reload@basic-reload-inject and igt@drv_module_reload@basic-reload by checking if the connector is registered instead of unregistered, as calling drm_connector_cleanup() on a connector that hasn't been registered with userspace yet should stay valid. - Remove unregistered_connector_check(), and just go back to what we were doing before in commit 4d80273976bf ("drm/atomic_helper: Disallow new modesets on unregistered connectors") except replacing READ_ONCE(connector->registered) with drm_connector_is_unregistered(). This gets rid of the behavior of allowing DPMS On<->Off, but that should be fine as it's more consistent with the UAPI we had before - danvet - s/drm_connector_unregistered/drm_connector_is_unregistered/ - danvet - Update documentation, fix some typos. Fixes: b5d29843d8ef ("drm/atomic_helper: Allow DPMS On<->Off changes for unregistered connectors") Cc: Ville Syrjälä Cc: Daniel Vetter Cc: Rodrigo Vivi Cc: stable@vger.kernel.org Cc: David Airlie Signed-off-by: Lyude Paul Reviewed-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20181016203946.9601-1-lyude@redhat.com (cherry picked from commit 39b50c603878f4f8ae541ac4088a805d588abc79) Fixes: e96550956fbc ("drm/atomic_helper: Disallow new modesets on unregistered connectors") Fixes: 34ca26a98ad6 ("drm/atomic_helper: Allow DPMS On<->Off changes for unregistered connectors") Cc: stable@vger.kernel.org Signed-off-by: Joonas Lahtinen --- drivers/gpu/drm/drm_atomic_helper.c | 21 ++++++++++- drivers/gpu/drm/drm_atomic_uapi.c | 21 ----------- drivers/gpu/drm/drm_connector.c | 11 +++--- drivers/gpu/drm/i915/intel_dp_mst.c | 8 ++--- include/drm/drm_connector.h | 71 +++++++++++++++++++++++++++++++++++-- 5 files changed, 99 insertions(+), 33 deletions(-) (limited to 'include/drm') diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index e49b22381048..1cc3a045ec2f 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -308,6 +308,26 @@ update_connector_routing(struct drm_atomic_state *state, return 0; } + crtc_state = drm_atomic_get_new_crtc_state(state, + new_connector_state->crtc); + /* + * For compatibility with legacy users, we want to make sure that + * we allow DPMS On->Off modesets on unregistered connectors. Modesets + * which would result in anything else must be considered invalid, to + * avoid turning on new displays on dead connectors. + * + * Since the connector can be unregistered at any point during an + * atomic check or commit, this is racy. But that's OK: all we care + * about is ensuring that userspace can't do anything but shut off the + * display on a connector that was destroyed after its been notified, + * not before. + */ + if (drm_connector_is_unregistered(connector) && crtc_state->active) { + DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] is not registered\n", + connector->base.id, connector->name); + return -EINVAL; + } + funcs = connector->helper_private; if (funcs->atomic_best_encoder) @@ -352,7 +372,6 @@ update_connector_routing(struct drm_atomic_state *state, set_best_encoder(state, new_connector_state, new_encoder); - crtc_state = drm_atomic_get_new_crtc_state(state, new_connector_state->crtc); crtc_state->connectors_changed = true; DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] using [ENCODER:%d:%s] on [CRTC:%d:%s]\n", diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c index a22d6f269b07..d5b7f315098c 100644 --- a/drivers/gpu/drm/drm_atomic_uapi.c +++ b/drivers/gpu/drm/drm_atomic_uapi.c @@ -299,27 +299,6 @@ drm_atomic_set_crtc_for_connector(struct drm_connector_state *conn_state, struct drm_connector *connector = conn_state->connector; struct drm_crtc_state *crtc_state; - /* - * For compatibility with legacy users, we want to make sure that - * we allow DPMS On<->Off modesets on unregistered connectors, since - * legacy modesetting users will not be expecting these to fail. We do - * not however, want to allow legacy users to assign a connector - * that's been unregistered from sysfs to another CRTC, since doing - * this with a now non-existent connector could potentially leave us - * in an invalid state. - * - * Since the connector can be unregistered at any point during an - * atomic check or commit, this is racy. But that's OK: all we care - * about is ensuring that userspace can't use this connector for new - * configurations after it's been notified that the connector is no - * longer present. - */ - if (!READ_ONCE(connector->registered) && crtc) { - DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] is not registered\n", - connector->base.id, connector->name); - return -EINVAL; - } - if (conn_state->crtc == crtc) return 0; diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c index 1e40e5decbe9..4943cef178be 100644 --- a/drivers/gpu/drm/drm_connector.c +++ b/drivers/gpu/drm/drm_connector.c @@ -379,7 +379,8 @@ void drm_connector_cleanup(struct drm_connector *connector) /* The connector should have been removed from userspace long before * it is finally destroyed. */ - if (WARN_ON(connector->registered)) + if (WARN_ON(connector->registration_state == + DRM_CONNECTOR_REGISTERED)) drm_connector_unregister(connector); if (connector->tile_group) { @@ -436,7 +437,7 @@ int drm_connector_register(struct drm_connector *connector) return 0; mutex_lock(&connector->mutex); - if (connector->registered) + if (connector->registration_state != DRM_CONNECTOR_INITIALIZING) goto unlock; ret = drm_sysfs_connector_add(connector); @@ -456,7 +457,7 @@ int drm_connector_register(struct drm_connector *connector) drm_mode_object_register(connector->dev, &connector->base); - connector->registered = true; + connector->registration_state = DRM_CONNECTOR_REGISTERED; goto unlock; err_debugfs: @@ -478,7 +479,7 @@ EXPORT_SYMBOL(drm_connector_register); void drm_connector_unregister(struct drm_connector *connector) { mutex_lock(&connector->mutex); - if (!connector->registered) { + if (connector->registration_state != DRM_CONNECTOR_REGISTERED) { mutex_unlock(&connector->mutex); return; } @@ -489,7 +490,7 @@ void drm_connector_unregister(struct drm_connector *connector) drm_sysfs_connector_remove(connector); drm_debugfs_connector_remove(connector); - connector->registered = false; + connector->registration_state = DRM_CONNECTOR_UNREGISTERED; mutex_unlock(&connector->mutex); } EXPORT_SYMBOL(drm_connector_unregister); diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c index 7f155b4f1a7d..1b00f8ea145b 100644 --- a/drivers/gpu/drm/i915/intel_dp_mst.c +++ b/drivers/gpu/drm/i915/intel_dp_mst.c @@ -77,7 +77,7 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder, pipe_config->pbn = mst_pbn; /* Zombie connectors can't have VCPI slots */ - if (READ_ONCE(connector->registered)) { + if (!drm_connector_is_unregistered(connector)) { slots = drm_dp_atomic_find_vcpi_slots(state, &intel_dp->mst_mgr, port, @@ -313,7 +313,7 @@ static int intel_dp_mst_get_ddc_modes(struct drm_connector *connector) struct edid *edid; int ret; - if (!READ_ONCE(connector->registered)) + if (drm_connector_is_unregistered(connector)) return intel_connector_update_modes(connector, NULL); edid = drm_dp_mst_get_edid(connector, &intel_dp->mst_mgr, intel_connector->port); @@ -329,7 +329,7 @@ intel_dp_mst_detect(struct drm_connector *connector, bool force) struct intel_connector *intel_connector = to_intel_connector(connector); struct intel_dp *intel_dp = intel_connector->mst_port; - if (!READ_ONCE(connector->registered)) + if (drm_connector_is_unregistered(connector)) return connector_status_disconnected; return drm_dp_mst_detect_port(connector, &intel_dp->mst_mgr, intel_connector->port); @@ -372,7 +372,7 @@ intel_dp_mst_mode_valid(struct drm_connector *connector, int bpp = 24; /* MST uses fixed bpp */ int max_rate, mode_rate, max_lanes, max_link_clock; - if (!READ_ONCE(connector->registered)) + if (drm_connector_is_unregistered(connector)) return MODE_ERROR; if (mode->flags & DRM_MODE_FLAG_DBLSCAN) diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h index 91a877fa00cb..9ccad6b062f2 100644 --- a/include/drm/drm_connector.h +++ b/include/drm/drm_connector.h @@ -82,6 +82,53 @@ enum drm_connector_status { connector_status_unknown = 3, }; +/** + * enum drm_connector_registration_status - userspace registration status for + * a &drm_connector + * + * This enum is used to track the status of initializing a connector and + * registering it with userspace, so that DRM can prevent bogus modesets on + * connectors that no longer exist. + */ +enum drm_connector_registration_state { + /** + * @DRM_CONNECTOR_INITIALIZING: The connector has just been created, + * but has yet to be exposed to userspace. There should be no + * additional restrictions to how the state of this connector may be + * modified. + */ + DRM_CONNECTOR_INITIALIZING = 0, + + /** + * @DRM_CONNECTOR_REGISTERED: The connector has been fully initialized + * and registered with sysfs, as such it has been exposed to + * userspace. There should be no additional restrictions to how the + * state of this connector may be modified. + */ + DRM_CONNECTOR_REGISTERED = 1, + + /** + * @DRM_CONNECTOR_UNREGISTERED: The connector has either been exposed + * to userspace and has since been unregistered and removed from + * userspace, or the connector was unregistered before it had a chance + * to be exposed to userspace (e.g. still in the + * @DRM_CONNECTOR_INITIALIZING state). When a connector is + * unregistered, there are additional restrictions to how its state + * may be modified: + * + * - An unregistered connector may only have its DPMS changed from + * On->Off. Once DPMS is changed to Off, it may not be switched back + * to On. + * - Modesets are not allowed on unregistered connectors, unless they + * would result in disabling its assigned CRTCs. This means + * disabling a CRTC on an unregistered connector is OK, but enabling + * one is not. + * - Removing a CRTC from an unregistered connector is OK, but new + * CRTCs may never be assigned to an unregistered connector. + */ + DRM_CONNECTOR_UNREGISTERED = 2, +}; + enum subpixel_order { SubPixelUnknown = 0, SubPixelHorizontalRGB, @@ -853,10 +900,12 @@ struct drm_connector { bool ycbcr_420_allowed; /** - * @registered: Is this connector exposed (registered) with userspace? + * @registration_state: Is this connector initializing, exposed + * (registered) with userspace, or unregistered? + * * Protected by @mutex. */ - bool registered; + enum drm_connector_registration_state registration_state; /** * @modes: @@ -1166,6 +1215,24 @@ static inline void drm_connector_unreference(struct drm_connector *connector) drm_connector_put(connector); } +/** + * drm_connector_is_unregistered - has the connector been unregistered from + * userspace? + * @connector: DRM connector + * + * Checks whether or not @connector has been unregistered from userspace. + * + * Returns: + * True if the connector was unregistered, false if the connector is + * registered or has not yet been registered with userspace. + */ +static inline bool +drm_connector_is_unregistered(struct drm_connector *connector) +{ + return READ_ONCE(connector->registration_state) == + DRM_CONNECTOR_UNREGISTERED; +} + const char *drm_get_connector_status_name(enum drm_connector_status status); const char *drm_get_subpixel_order_name(enum subpixel_order order); const char *drm_get_dpms_name(int val); -- cgit v1.2.3