aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/i915
diff options
context:
space:
mode:
authorKeith Packard <keithp@keithp.com>2011-07-25 10:04:56 -0700
committerGreg Kroah-Hartman <gregkh@suse.de>2011-08-15 18:31:35 -0700
commit8b01249b9fe0697eb66e8d0bf41a714d91d039ce (patch)
tree751403dcf6ee23da953ed2d8ca10da671fc18137 /drivers/gpu/drm/i915
parent3f6846490d30a4b6e127bc522615db58721a8cdc (diff)
downloadkernel_samsung_smdk4412-8b01249b9fe0697eb66e8d0bf41a714d91d039ce.zip
kernel_samsung_smdk4412-8b01249b9fe0697eb66e8d0bf41a714d91d039ce.tar.gz
kernel_samsung_smdk4412-8b01249b9fe0697eb66e8d0bf41a714d91d039ce.tar.bz2
drm/i915: Hold mode_config->mutex during hotplug processing
commit a65e34c79c88895766ab1f8a5afa451eed26622b upstream. Hotplug detection is a mode setting operation and must hold the struct_mutex or risk colliding with other mode setting operations. In particular, the display port hotplug function attempts to re-train the link if the monitor is supposed to be running when plugged back in. If that happens while mode setting is underway, the link will get scrambled, leaving it in an inconsistent state. This is a special case -- usually the driver mode setting entry points are covered by the upper level DRM code, but in this case the function is invoked as a work function not under the control of DRM. Signed-off-by: Keith Packard <keithp@keithp.com> Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/gpu/drm/i915')
-rw-r--r--drivers/gpu/drm/i915/i915_irq.c3
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 3b03f85..9da2a2c 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -306,6 +306,7 @@ static void i915_hotplug_work_func(struct work_struct *work)
struct drm_mode_config *mode_config = &dev->mode_config;
struct intel_encoder *encoder;
+ mutex_lock(&mode_config->mutex);
DRM_DEBUG_KMS("running encoder hotplug functions\n");
list_for_each_entry(encoder, &mode_config->encoder_list, base.head)
@@ -314,6 +315,8 @@ static void i915_hotplug_work_func(struct work_struct *work)
/* Just fire off a uevent and let userspace tell us what to do */
drm_helper_hpd_irq_event(dev);
+
+ mutex_unlock(&mode_config->mutex);
}
static void i915_handle_rps_change(struct drm_device *dev)