From 54a9f8e5ac230b33d8b027b880476d73a4bf5026 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Tue, 8 Sep 2015 17:30:52 -0700 Subject: CHROMIUM: android: fix warning when releasing active sync point Userspace can close the sync device while there are still active fence points, in which case kernel produces the following warning: [ 43.853176] ------------[ cut here ]------------ [ 43.857834] WARNING: CPU: 0 PID: 892 at /mnt/host/source/src/third_party/kernel/v3.18/drivers/staging/android/sync.c:439 android_fence_release+0x88/0x104() [ 43.871741] CPU: 0 PID: 892 Comm: Binder_5 Tainted: G U 3.18.0-07661-g0550ce9 #1 [ 43.880176] Hardware name: Google Tegra210 Smaug Rev 1+ (DT) [ 43.885834] Call trace: [ 43.888294] [] dump_backtrace+0x0/0x10c [ 43.893697] [] show_stack+0x10/0x1c [ 43.898756] [] dump_stack+0x74/0xb8 [ 43.903814] [] warn_slowpath_common+0x84/0xb0 [ 43.909736] [] warn_slowpath_null+0x14/0x20 [ 43.915482] [] android_fence_release+0x84/0x104 [ 43.921582] [] fence_release+0x104/0x134 [ 43.927066] [] sync_fence_free+0x74/0x9c [ 43.932552] [] sync_fence_release+0x34/0x48 [ 43.938304] [] __fput+0x100/0x1b8 [ 43.943185] [] ____fput+0x8/0x14 [ 43.947982] [] task_work_run+0xb0/0xe4 [ 43.953297] [] do_notify_resume+0x44/0x5c [ 43.958867] ---[ end trace 5a2aa4027cc5d171 ]--- Let's fix it by introducing a new optional callback (disable_signaling) to fence operations so that drivers can do proper clean ups when we remove last callback for given fence. BUG=chrome-os-partner:40303 TEST=Boot Smaug and observe that warning is gone. Change-Id: I05c34dcf74438c28405438c7ead0706b1f810fff Signed-off-by: Dmitry Torokhov Reviewed-on: https://chromium-review.googlesource.com/303409 Reviewed-by: Andrew Bresticker --- drivers/dma-buf/fence.c | 6 +++++- drivers/staging/android/sync.c | 8 ++++++++ include/linux/fence.h | 2 ++ 3 files changed, 15 insertions(+), 1 deletion(-) diff --git a/drivers/dma-buf/fence.c b/drivers/dma-buf/fence.c index 7bb9d65d9a2c..ae50011fba3e 100644 --- a/drivers/dma-buf/fence.c +++ b/drivers/dma-buf/fence.c @@ -301,8 +301,12 @@ fence_remove_callback(struct fence *fence, struct fence_cb *cb) spin_lock_irqsave(fence->lock, flags); ret = !list_empty(&cb->node); - if (ret) + if (ret) { list_del_init(&cb->node); + if (list_empty(&fence->cb_list)) + if (fence->ops->disable_signaling) + fence->ops->disable_signaling(fence); + } spin_unlock_irqrestore(fence->lock, flags); diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c index f83e00c78051..a18d1c55aca6 100644 --- a/drivers/staging/android/sync.c +++ b/drivers/staging/android/sync.c @@ -465,6 +465,13 @@ static bool android_fence_enable_signaling(struct fence *fence) return true; } +static void android_fence_disable_signaling(struct fence *fence) +{ + struct sync_pt *pt = container_of(fence, struct sync_pt, base); + + list_del_init(&pt->active_list); +} + static int android_fence_fill_driver_data(struct fence *fence, void *data, int size) { @@ -508,6 +515,7 @@ static const struct fence_ops android_fence_ops = { .get_driver_name = android_fence_get_driver_name, .get_timeline_name = android_fence_get_timeline_name, .enable_signaling = android_fence_enable_signaling, + .disable_signaling = android_fence_disable_signaling, .signaled = android_fence_signaled, .wait = fence_default_wait, .release = android_fence_release, diff --git a/include/linux/fence.h b/include/linux/fence.h index d174585b874b..1c94759e7148 100644 --- a/include/linux/fence.h +++ b/include/linux/fence.h @@ -107,6 +107,7 @@ struct fence_cb { * @get_driver_name: returns the driver name. * @get_timeline_name: return the name of the context this fence belongs to. * @enable_signaling: enable software signaling of fence. + * @disable_signaling: disable software signaling of fence (optional). * @signaled: [optional] peek whether the fence is signaled, can be null. * @wait: custom wait implementation, or fence_default_wait. * @release: [optional] called on destruction of fence, can be null @@ -166,6 +167,7 @@ struct fence_ops { const char * (*get_driver_name)(struct fence *fence); const char * (*get_timeline_name)(struct fence *fence); bool (*enable_signaling)(struct fence *fence); + void (*disable_signaling)(struct fence *fence); bool (*signaled)(struct fence *fence); signed long (*wait)(struct fence *fence, bool intr, signed long timeout); void (*release)(struct fence *fence); -- cgit v1.2.3