From 171901d15deeef61aa8e1b0d0772404f39691b73 Mon Sep 17 00:00:00 2001 From: Thomas Hellstrom Date: Mon, 2 Mar 2009 11:10:55 +0100 Subject: drm: Wake up all lock waiters when the master disappears. Currently only one waiter is woken up, leaving other waiters hanging waiting for the DRM lock. Signed-off-by: Thomas Hellstrom Signed-off-by: Dave Airlie --- drivers/gpu/drm/drm_stub.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/gpu/drm/drm_stub.c') diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c index 46bb923b097c..7b251dd70811 100644 --- a/drivers/gpu/drm/drm_stub.c +++ b/drivers/gpu/drm/drm_stub.c @@ -151,7 +151,7 @@ static void drm_master_destroy(struct kref *kref) dev->sigdata.lock = NULL; master->lock.hw_lock = NULL; master->lock.file_priv = NULL; - wake_up_interruptible(&master->lock.lock_queue); + wake_up_interruptible_all(&master->lock.lock_queue); } drm_free(master, sizeof(*master), DRM_MEM_DRIVER); -- cgit v1.2.3-70-g09d2 From fda714c29cdf360464059044b221450decb4b913 Mon Sep 17 00:00:00 2001 From: Thomas Hellstrom Date: Mon, 2 Mar 2009 11:10:56 +0100 Subject: drm: Avoid client deadlocks when the master disappears. This is done by 1) Wake up lock waiters when we close the master file descriptor. Not when the master structure is removed, since the latter requires the waiters themselves to release the refcount on the master structure -> Deadlock. 2) Send a SIGTERM to all clients waiting for the lock. Normally these clients will get a SIGPIPE when the X server dies, but clients may also spin trying to grab the DRM lock, without getting any sort of notification. Signed-off-by: Thomas Hellstrom Signed-off-by: Dave Airlie --- drivers/gpu/drm/drm_fops.c | 14 ++++++++++++++ drivers/gpu/drm/drm_lock.c | 1 + drivers/gpu/drm/drm_stub.c | 8 -------- 3 files changed, 15 insertions(+), 8 deletions(-) (limited to 'drivers/gpu/drm/drm_stub.c') diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c index 6c020fe5431c..f52663ebe016 100644 --- a/drivers/gpu/drm/drm_fops.c +++ b/drivers/gpu/drm/drm_fops.c @@ -484,6 +484,7 @@ int drm_release(struct inode *inode, struct file *filp) mutex_lock(&dev->struct_mutex); if (file_priv->is_master) { + struct drm_master *master = file_priv->master; struct drm_file *temp; list_for_each_entry(temp, &dev->filelist, lhead) { if ((temp->master == file_priv->master) && @@ -491,6 +492,19 @@ int drm_release(struct inode *inode, struct file *filp) temp->authenticated = 0; } + /** + * Since the master is disappearing, so is the + * possibility to lock. + */ + + if (master->lock.hw_lock) { + if (dev->sigdata.lock == master->lock.hw_lock) + dev->sigdata.lock = NULL; + master->lock.hw_lock = NULL; + master->lock.file_priv = NULL; + wake_up_interruptible_all(&master->lock.lock_queue); + } + if (file_priv->minor->master == file_priv->master) { /* drop the reference held my the minor */ drm_master_put(&file_priv->minor->master); diff --git a/drivers/gpu/drm/drm_lock.c b/drivers/gpu/drm/drm_lock.c index b03586fdabbd..e2f70a516c34 100644 --- a/drivers/gpu/drm/drm_lock.c +++ b/drivers/gpu/drm/drm_lock.c @@ -80,6 +80,7 @@ int drm_lock(struct drm_device *dev, void *data, struct drm_file *file_priv) __set_current_state(TASK_INTERRUPTIBLE); if (!master->lock.hw_lock) { /* Device has been unregistered */ + send_sig(SIGTERM, current, 0); ret = -EINTR; break; } diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c index 7b251dd70811..096e2a37446d 100644 --- a/drivers/gpu/drm/drm_stub.c +++ b/drivers/gpu/drm/drm_stub.c @@ -146,14 +146,6 @@ static void drm_master_destroy(struct kref *kref) drm_ht_remove(&master->magiclist); - if (master->lock.hw_lock) { - if (dev->sigdata.lock == master->lock.hw_lock) - dev->sigdata.lock = NULL; - master->lock.hw_lock = NULL; - master->lock.file_priv = NULL; - wake_up_interruptible_all(&master->lock.lock_queue); - } - drm_free(master, sizeof(*master), DRM_MEM_DRIVER); } -- cgit v1.2.3-70-g09d2 From 5ad8b7d12605e88d1e532061699102797fdefe08 Mon Sep 17 00:00:00 2001 From: Helge Bahmann Date: Wed, 4 Mar 2009 21:49:14 +1000 Subject: drm: fix double lock typo [airlied: you shall not retype patches from other trees half asleep] Signed-of-by: Dave Airlie --- drivers/gpu/drm/drm_stub.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/gpu/drm/drm_stub.c') diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c index 096e2a37446d..7c8b15b22bf2 100644 --- a/drivers/gpu/drm/drm_stub.c +++ b/drivers/gpu/drm/drm_stub.c @@ -168,7 +168,7 @@ int drm_setmaster_ioctl(struct drm_device *dev, void *data, file_priv->minor->master != file_priv->master) { mutex_lock(&dev->struct_mutex); file_priv->minor->master = drm_master_get(file_priv->master); - mutex_lock(&dev->struct_mutex); + mutex_unlock(&dev->struct_mutex); } return 0; -- cgit v1.2.3-70-g09d2