Bug 229614

Summary:	[ BigSur EWS] webrtc/video-mediastreamtrack-stats.html is a flaky crash / failing
Product:	WebKit	Reporter:	ayumi_kojima
Component:	WebRTC	Assignee:	Nobody <webkit-unassigned>
Status:	NEW ---
Severity:	Normal	CC:	eric.carlson, webkit-bot-watchers-bugzilla, webkit-bug-importer, youennf
Priority:	P2	Keywords:	InRadar
Version:	WebKit Nightly Build
Hardware:	Unspecified
OS:	Unspecified

Description ayumi_kojima 2021-08-27 09:50:57 PDT

webrtc/video-mediastreamtrack-stats.html

Is a flaky crash on macOS-AppleSilicon-Big-Sur-Debug-WK2-Tests-EWS.

According to the history, the test has been flaky failing on Big Sur wk2 intel but I don't see any crash: https://results.webkit.org/?suite=layout-tests&test=webrtc%2Fvideo-mediastreamtrack-stats.html

It looks like the flaky crash started on EWS at this build: https://ews-build.webkit.org/#/builders/60/builds/9803

Crash log: 

No crash log found for GPUProcess:95140.

stdout:

stderr:
LEAK: 3 WebPageProxy

Diff:

--- /Volumes/Data/worker/bigsur-release-tests-wk2/build/layout-test-results/webrtc/video-mediastreamtrack-stats-expected.txt
+++ /Volumes/Data/worker/bigsur-release-tests-wk2/build/layout-test-results/webrtc/video-mediastreamtrack-stats-actual.txt
@@ -1,3 +1,3 @@
 
-PASS Basic video media stream track stats
+FAIL Basic video media stream track stats assert_equals: expected (number) 480 but got (undefined) undefined

Comment 1 ayumi_kojima 2021-08-27 11:54:16 PDT

Marked expectation: https://trac.webkit.org/changeset/281710/webkit

Comment 2 Radar WebKit Bug Importer 2021-08-27 11:54:40 PDT

<rdar://problem/82448494>

Comment 3 ayumi_kojima 2021-08-27 11:55:48 PDT

I was able to reproduce the failure at TOT locally on my intel machine using: run-webkit-tests --iteration 50 webrtc/video-mediastreamtrack-stats.html

Comment 4 Eric Carlson 2021-08-27 15:46:43 PDT

From https://ews-build.s3-us-west-2.amazonaws.com/macOS-AppleSilicon-Big-Sur-Debug-WK2-Tests-EWS/r435500-9803/com.apple.WebKit.GPU.Development-95140-crash-log.txt

Crashed Thread:        18  Dispatch queue: vtencoder-callback-queue-0x14239fcf0

Exception Type:        EXC_BAD_ACCESS (SIGSEGV)
Exception Codes:       KERN_INVALID_ADDRESS at 0x0000000000000000
Exception Note:        EXC_CORPSE_NOTIFY

Termination Signal:    Segmentation fault: 11
Termination Reason:    Namespace SIGNAL, Code 0xb
Terminating Process:   exc handler [95140]


Thread 18 Crashed:: Dispatch queue: vtencoder-callback-queue-0x14239fcf0
0   libsystem_pthread.dylib       	0x0000000180d85d9c pthread_mutex_lock + 0
1   com.apple.VideoToolbox        	0x000000018bdd4858 VTEncoderSessionEmitEncodedFrame + 404
2   com.apple.VideoToolbox        	0x000000018be82bb4 0x18bdc1000 + 793524
3   libxpc.dylib                  	0x0000000180af57d0 _xpc_connection_call_event_handler + 172
4   libxpc.dylib                  	0x0000000180af432c _xpc_connection_mach_event + 968
5   libdispatch.dylib             	0x0000000180bdbf8c _dispatch_client_callout4 + 20
6   libdispatch.dylib             	0x0000000180bf7114 _dispatch_mach_msg_invoke + 476
7   libdispatch.dylib             	0x0000000180be3570 _dispatch_lane_serial_drain + 308
8   libdispatch.dylib             	0x0000000180bf7e78 _dispatch_mach_invoke + 464
9   libdispatch.dylib             	0x0000000180be3570 _dispatch_lane_serial_drain + 308
10  libdispatch.dylib             	0x0000000180be42d8 _dispatch_lane_invoke + 456
11  libdispatch.dylib             	0x0000000180bed684 _dispatch_root_queue_drain + 388
12  libdispatch.dylib             	0x0000000180bed41c _dispatch_worker_thread + 236
13  libsystem_pthread.dylib       	0x0000000180d8b878 _pthread_start + 320
14  libsystem_pthread.dylib       	0x0000000180d865e0 thread_start + 8