diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 9b9a30c11e1c6fbcc8c214ed558f4d636d346280..4a1d0613dfe7b32bc1a0a397d2f2350d99a20b2b 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -6310,6 +6310,9 @@ int intel_atomic_check(struct drm_device *dev,
int ret, i;
bool any_ms = false;
+ if (!intel_display_driver_check_access(dev_priv))
+ return -ENODEV;
+
for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
new_crtc_state, i) {
/*
diff --git a/drivers/gpu/drm/i915/display/intel_display_core.h b/drivers/gpu/drm/i915/display/intel_display_core.h
index 7349a2b928c0756827567d90f92acd67cd3df49f..cd3b34459b875203123eaf10dabd7fc5bbbdce25 100644
--- a/drivers/gpu/drm/i915/display/intel_display_core.h
+++ b/drivers/gpu/drm/i915/display/intel_display_core.h
@@ -28,6 +28,8 @@
#include "intel_opregion.h"
#include "intel_wm_types.h"
+struct task_struct;
+
struct drm_i915_private;
struct drm_property;
struct drm_property_blob;
@@ -295,6 +297,11 @@ struct intel_display {
const struct intel_audio_funcs *audio;
} funcs;
+ struct {
+ bool any_task_allowed;
+ struct task_struct *allowed_task;
+ } access;
+
struct {
/* backlight registers and fields in struct intel_panel */
struct mutex lock;
diff --git a/drivers/gpu/drm/i915/display/intel_display_driver.c b/drivers/gpu/drm/i915/display/intel_display_driver.c
index 1974f2394a5182141c202fc4c1287fd0be3735a1..dcdd26eefaaf45a6e059147a9e4c06347a6bae4d 100644
--- a/drivers/gpu/drm/i915/display/intel_display_driver.c
+++ b/drivers/gpu/drm/i915/display/intel_display_driver.c
@@ -45,6 +45,7 @@
#include "intel_hdcp.h"
#include "intel_hotplug.h"
#include "intel_hti.h"
+#include "intel_modeset_lock.h"
#include "intel_modeset_setup.h"
#include "intel_opregion.h"
#include "intel_overlay.h"
@@ -276,6 +277,135 @@ int intel_display_driver_probe_noirq(struct drm_i915_private *i915)
return ret;
}
+static void set_display_access(struct drm_i915_private *i915,
+ bool any_task_allowed,
+ struct task_struct *allowed_task)
+{
+ struct drm_modeset_acquire_ctx ctx;
+ int err;
+
+ intel_modeset_lock_ctx_retry(&ctx, NULL, 0, err) {
+ err = drm_modeset_lock_all_ctx(&i915->drm, &ctx);
+ if (err)
+ continue;
+
+ i915->display.access.any_task_allowed = any_task_allowed;
+ i915->display.access.allowed_task = allowed_task;
+ }
+
+ drm_WARN_ON(&i915->drm, err);
+}
+
+/**
+ * intel_display_driver_enable_user_access - Enable display HW access for all threads
+ * @i915: i915 device instance
+ *
+ * Enable the display HW access for all threads. Examples for such accesses
+ * are modeset commits and connector probing.
+ *
+ * This function should be called during driver loading and system resume once
+ * all the HW initialization steps are done.
+ */
+void intel_display_driver_enable_user_access(struct drm_i915_private *i915)
+{
+ set_display_access(i915, true, NULL);
+}
+
+/**
+ * intel_display_driver_disable_user_access - Disable display HW access for user threads
+ * @i915: i915 device instance
+ *
+ * Disable the display HW access for user threads. Examples for such accesses
+ * are modeset commits and connector probing. For the current thread the
+ * access is still enabled, which should only perform HW init/deinit
+ * programming (as the initial modeset during driver loading or the disabling
+ * modeset during driver unloading and system suspend/shutdown). This function
+ * should be followed by calling either intel_display_driver_enable_user_access()
+ * after completing the HW init programming or
+ * intel_display_driver_suspend_access() after completing the HW deinit
+ * programming.
+ *
+ * This function should be called during driver loading/unloading and system
+ * suspend/shutdown before starting the HW init/deinit programming.
+ */
+void intel_display_driver_disable_user_access(struct drm_i915_private *i915)
+{
+ set_display_access(i915, false, current);
+}
+
+/**
+ * intel_display_driver_suspend_access - Suspend display HW access for all threads
+ * @i915: i915 device instance
+ *
+ * Disable the display HW access for all threads. Examples for such accesses
+ * are modeset commits and connector probing. This call should be either
+ * followed by calling intel_display_driver_resume_access(), or the driver
+ * should be unloaded/shutdown.
+ *
+ * This function should be called during driver unloading and system
+ * suspend/shutdown after completing the HW deinit programming.
+ */
+void intel_display_driver_suspend_access(struct drm_i915_private *i915)
+{
+ set_display_access(i915, false, NULL);
+}
+
+/**
+ * intel_display_driver_resume_access - Resume display HW access for the resume thread
+ * @i915: i915 device instance
+ *
+ * Enable the display HW access for the current resume thread, keeping the
+ * access disabled for all other (user) threads. Examples for such accesses
+ * are modeset commits and connector probing. The resume thread should only
+ * perform HW init programming (as the restoring modeset). This function
+ * should be followed by calling intel_display_driver_enable_user_access(),
+ * after completing the HW init programming steps.
+ *
+ * This function should be called during system resume before starting the HW
+ * init steps.
+ */
+void intel_display_driver_resume_access(struct drm_i915_private *i915)
+{
+ set_display_access(i915, false, current);
+}
+
+/**
+ * intel_display_driver_check_access - Check if the current thread has disaplay HW access
+ * @i915: i915 device instance
+ *
+ * Check whether the current thread has display HW access, print a debug
+ * message if it doesn't. Such accesses are modeset commits and connector
+ * probing. If the function returns %false any HW access should be prevented.
+ *
+ * Returns %true if the current thread has display HW access, %false
+ * otherwise.
+ */
+bool intel_display_driver_check_access(struct drm_i915_private *i915)
+{
+ char comm[TASK_COMM_LEN];
+ char current_task[TASK_COMM_LEN + 16];
+ char allowed_task[TASK_COMM_LEN + 16] = "none";
+
+ if (i915->display.access.any_task_allowed ||
+ i915->display.access.allowed_task == current)
+ return true;
+
+ snprintf(current_task, sizeof(current_task), "%s[%d]",
+ get_task_comm(comm, current),
+ task_pid_vnr(current));
+
+ if (i915->display.access.allowed_task)
+ snprintf(allowed_task, sizeof(allowed_task), "%s[%d]",
+ get_task_comm(comm, i915->display.access.allowed_task),
+ task_pid_vnr(i915->display.access.allowed_task));
+
+ drm_dbg_kms(&i915->drm,
+ "Reject display access from task %s (allowed to %s)\n",
+ current_task, allowed_task);
+
+ return false;
+}
+
/* part #2: call after irq install, but before gem init */
int intel_display_driver_probe_nogem(struct drm_i915_private *i915)
{
@@ -326,6 +456,8 @@ int intel_display_driver_probe_nogem(struct drm_i915_private *i915)
intel_vga_disable(i915);
intel_setup_outputs(i915);
+ intel_display_driver_disable_user_access(i915);
+
drm_modeset_lock_all(dev);
intel_modeset_setup_hw_state(i915, dev->mode_config.acquire_ctx);
intel_acpi_assign_connector_fwnodes(i915);
@@ -393,6 +525,8 @@ void intel_display_driver_register(struct drm_i915_private *i915)
intel_audio_init(i915);
+ intel_display_driver_enable_user_access(i915);
+
intel_display_debugfs_register(i915);
/*
@@ -440,6 +574,8 @@ void intel_display_driver_remove_noirq(struct drm_i915_private *i915)
if (!HAS_DISPLAY(i915))
return;
+ intel_display_driver_suspend_access(i915);
+
/*
* Due to the hpd irq storm handling the hotplug work can re-arm the
* poll handlers. Hence disable polling after hpd handling is shut down.
@@ -493,6 +629,8 @@ void intel_display_driver_unregister(struct drm_i915_private *i915)
*/
drm_kms_helper_poll_fini(&i915->drm);
+ intel_display_driver_disable_user_access(i915);
+
intel_audio_deinit(i915);
drm_atomic_helper_shutdown(&i915->drm);
diff --git a/drivers/gpu/drm/i915/display/intel_display_driver.h b/drivers/gpu/drm/i915/display/intel_display_driver.h
index c276a58ee3293f8f0e1761154a28d0ce46e046ba..42cc4af6d3fd5bc60628ecbeb0741c20accdbdbf 100644
--- a/drivers/gpu/drm/i915/display/intel_display_driver.h
+++ b/drivers/gpu/drm/i915/display/intel_display_driver.h
@@ -32,5 +32,11 @@ int __intel_display_driver_resume(struct drm_i915_private *i915,
struct drm_atomic_state *state,
struct drm_modeset_acquire_ctx *ctx);
+void intel_display_driver_enable_user_access(struct drm_i915_private *i915);
+void intel_display_driver_disable_user_access(struct drm_i915_private *i915);
+void intel_display_driver_suspend_access(struct drm_i915_private *i915);
+void intel_display_driver_resume_access(struct drm_i915_private *i915);
+bool intel_display_driver_check_access(struct drm_i915_private *i915);
+
#endif /* __INTEL_DISPLAY_DRIVER_H__ */
diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
index 8005a29e78ca75b36f67fdc16c48db190b430f9f..7603771ae107b14a978b0a5f0ff948332819d393 100644
--- a/drivers/gpu/drm/i915/i915_driver.c
+++ b/drivers/gpu/drm/i915/i915_driver.c
@@ -1005,6 +1005,7 @@ void i915_driver_shutdown(struct drm_i915_private *i915)
intel_fbdev_set_suspend(&i915->drm, FBINFO_STATE_SUSPENDED, true);
if (HAS_DISPLAY(i915)) {
drm_kms_helper_poll_disable(&i915->drm);
+ intel_display_driver_disable_user_access(i915);
drm_atomic_helper_shutdown(&i915->drm);
}
@@ -1014,6 +1015,9 @@ void i915_driver_shutdown(struct drm_i915_private *i915)
intel_runtime_pm_disable_interrupts(i915);
intel_hpd_cancel_work(i915);
+ if (HAS_DISPLAY(i915))
+ intel_display_driver_suspend_access(i915);
+
intel_suspend_encoders(i915);
intel_shutdown_encoders(i915);
@@ -1081,8 +1085,10 @@ static int i915_drm_suspend(struct drm_device *dev)
* properly. */
intel_power_domains_disable(dev_priv);
intel_fbdev_set_suspend(dev, FBINFO_STATE_SUSPENDED, true);
- if (HAS_DISPLAY(dev_priv))
+ if (HAS_DISPLAY(dev_priv)) {
drm_kms_helper_poll_disable(dev);
+ intel_display_driver_disable_user_access(dev_priv);
+ }
pci_save_state(pdev);
@@ -1093,6 +1099,9 @@ static int i915_drm_suspend(struct drm_device *dev)
intel_runtime_pm_disable_interrupts(dev_priv);
intel_hpd_cancel_work(dev_priv);
+ if (HAS_DISPLAY(dev_priv))
+ intel_display_driver_suspend_access(dev_priv);
+
intel_suspend_encoders(dev_priv);
/* Must be called before GGTT is suspended. */
@@ -1242,14 +1251,20 @@ static int i915_drm_resume(struct drm_device *dev)
intel_display_driver_init_hw(dev_priv);
intel_clock_gating_init(dev_priv);
+
+ if (HAS_DISPLAY(dev_priv))
+ intel_display_driver_resume_access(dev_priv);
+
intel_hpd_init(dev_priv);
/* MST sideband requires HPD interrupts enabled */
intel_dp_mst_resume(dev_priv);
intel_display_driver_resume(dev_priv);
- if (HAS_DISPLAY(dev_priv))
+ if (HAS_DISPLAY(dev_priv)) {
+ intel_display_driver_enable_user_access(dev_priv);
drm_kms_helper_poll_enable(dev);
+ }
intel_hpd_poll_disable(dev_priv);
intel_opregion_resume(dev_priv);