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] [<ffffffc000207464>] dump_backtrace+0x0/0x10c
[ 43.893697] [<ffffffc000207580>] show_stack+0x10/0x1c
[ 43.898756] [<ffffffc000ab1258>] dump_stack+0x74/0xb8
[ 43.903814] [<ffffffc00021d414>] warn_slowpath_common+0x84/0xb0
[ 43.909736] [<ffffffc00021d530>] warn_slowpath_null+0x14/0x20
[ 43.915482] [<ffffffc00088aefc>] android_fence_release+0x84/0x104
[ 43.921582] [<ffffffc000671cc4>] fence_release+0x104/0x134
[ 43.927066] [<ffffffc00088b0cc>] sync_fence_free+0x74/0x9c
[ 43.932552] [<ffffffc00088b128>] sync_fence_release+0x34/0x48
[ 43.938304] [<ffffffc000317bbc>] __fput+0x100/0x1b8
[ 43.943185] [<ffffffc000317cc8>] ____fput+0x8/0x14
[ 43.947982] [<ffffffc000237f38>] task_work_run+0xb0/0xe4
[ 43.953297] [<ffffffc000207074>] 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 <dtor@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/303409
Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
[AmitP: Refactored it for upstream Sync framework changes.]
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
diff --git a/drivers/dma-buf/fence.c b/drivers/dma-buf/fence.c
index 4d51f9e..2453e07 100644
--- a/drivers/dma-buf/fence.c
+++ b/drivers/dma-buf/fence.c
@@ -304,8 +304,12 @@
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/dma-buf/sw_sync.c b/drivers/dma-buf/sw_sync.c
index 62e8e6d..454d3b3 100644
--- a/drivers/dma-buf/sw_sync.c
+++ b/drivers/dma-buf/sw_sync.c
@@ -234,6 +234,13 @@
return true;
}
+static void timeline_fence_disable_signaling(struct fence *fence)
+{
+ struct sync_pt *pt = container_of(fence, struct sync_pt, base);
+
+ list_del_init(&pt->active_list);
+}
+
static void timeline_fence_value_str(struct fence *fence,
char *str, int size)
{
@@ -252,6 +259,7 @@
.get_driver_name = timeline_fence_get_driver_name,
.get_timeline_name = timeline_fence_get_timeline_name,
.enable_signaling = timeline_fence_enable_signaling,
+ .disable_signaling = timeline_fence_disable_signaling,
.signaled = timeline_fence_signaled,
.wait = fence_default_wait,
.release = timeline_fence_release,
diff --git a/include/linux/fence.h b/include/linux/fence.h
index 0d76305..8d7265f 100644
--- a/include/linux/fence.h
+++ b/include/linux/fence.h
@@ -108,6 +108,7 @@
* @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
@@ -167,6 +168,7 @@
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);