Bug 195433 – [ iOS Sim ] Layout Test imported/w3c/web-platform-tests/webrtc/simplecall-no-ssrcs.https.html is a flaky crash

• Component: Tools / Tests
• Status: RESOLVED DUPLICATE

[Shawn Roberts]

The following layout test is failing on iOS Simulator

imported/w3c/web-platform-tests/webrtc/simplecall-no-ssrcs.https.html

Probable cause:

Unable to find exact point of regression. Test is failing with the oldest revision I can spade which is r228106

Reproduced locally with:

run-webkit-tests imported/w3c/web-platform-tests/webrtc/simplecall-no-ssrcs.https.html --iterations 500 -f --ios-simulator --exit-after-n-failures=5

Flakiness Dashboard:

https://webkit-test-results.webkit.org/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=imported%2Fw3c%2Fweb-platform-tests%2Fwebrtc%2Fsimplecall-no-ssrcs.https.html

Crash log:

https://build.webkit.org/results/Apple%20iOS%2012%20Simulator%20Release%20WK2%20(Tests)/r242586%20(3007)/imported/w3c/web-platform-tests/webrtc/simplecall-no-ssrcs.https-crash-log.txt

Time Awake Since Boot: 700000 seconds

System Integrity Protection: disabled

Crashed Thread:        0  Dispatch queue: com.apple.main-thread

Exception Type:        EXC_BAD_ACCESS (SIGSEGV)
Exception Codes:       KERN_INVALID_ADDRESS at 0x0000000000000010
Exception Note:        EXC_CORPSE_NOTIFY

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

VM Regions Near 0x10:
--> 
    __TEXT                 000000010747c000-000000010747d000 [    4K] r-x/rwx SM=COW  /Volumes/VOLUME/*/WebKit.framework/XPCServices/com.apple.WebKit.WebContent.xpc/com.apple.WebKit.WebContent.Development

Application Specific Information:
CRASHING TEST: imported/mozilla/svg/filters/filter-marked-line-09-expected.svg
CoreSimulator 581.2 - Device: Managed 1 - Runtime: iOS 12.1 (16B91) - DeviceType: iPhone SE

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0   com.apple.CoreFoundation      	0x0000000109bc20e0 CFBasicHashRemoveValue + 800
1   com.apple.CoreFoundation      	0x0000000109a8d0e8 CFDictionaryRemoveValue + 152
2   com.apple.VideoToolbox        	0x000000039f474fe7 VTPixelTransferSessionTransferImage + 5581
3   com.apple.VideoToolbox        	0x000000039f4dd814 VTPixelBufferConformerCopyConformedPixelBuffer + 2068
4   com.apple.WebCore             	0x0000000399494745 WebCore::PixelBufferConformerCV::convert(__CVBuffer*) + 117 (PixelBufferConformerCV.cpp:147)
5   com.apple.WebCore             	0x00000003981c42b9 WebCore::RealtimeOutgoingVideoSourceCocoa::convertToYUV(__CVBuffer*) + 233 (RealtimeOutgoingVideoSourceCocoa.mm:49)
6   com.apple.WebCore             	0x00000003994fbf5e WebCore::RealtimeOutgoingVideoSourceCocoa::sampleBufferUpdated(WebCore::MediaStreamTrackPrivate&, WebCore::MediaSample&) + 334 (RetainPtr.h:258)
7   com.apple.WebCore             	0x00000003994dc117 WebCore::MediaStreamTrackPrivate::forEachObserver(WTF::Function<void (WebCore::MediaStreamTrackPrivate::Observer&)> const&) const + 727 (Atomics.h:247)
8   com.apple.WebCore             	0x00000003994dcb76 WebCore::MediaStreamTrackPrivate::videoSampleAvailable(WebCore::MediaSample&) + 182 (MediaStreamTrackPrivate.cpp:241)
9   com.apple.WebCore             	0x00000003994de7c7 WebCore::RealtimeMediaSource::forEachObserver(WTF::Function<void (WebCore::RealtimeMediaSource::Observer&)> const&) const + 727 (Atomics.h:247)
10  com.apple.WebCore             	0x00000003994dea1b WebCore::RealtimeMediaSource::videoSampleAvailable(WebCore::MediaSample&) + 59 (RealtimeMediaSource.cpp:162)
11  com.apple.WebCore             	0x0000000398a625a6 WebCore::CanvasCaptureMediaStreamTrack::Source::captureCanvas() + 86 (utility:896)
12  com.apple.WebCore             	0x00000003993c1d4d WebCore::ThreadTimers::sharedTimerFiredInternal() + 173 (ThreadTimers.cpp:132)
13  com.apple.WebCore             	0x00000003993e770f WebCore::timerFired(__CFRunLoopTimer*, void*) + 31 (MainThreadSharedTimerCF.cpp:75)

[Radar WebKit Bug Importer]

<rdar://problem/48689482>

[Shawn Roberts]

Failed with several revisions during testing.

242605, 242280, 242278, 240000, 23701, 228106

All revisions failed all 5 times during the test cycle within 100 iterations except for revision 228106 failed with only 1 crash.

[Ryan Haddad]

Skipped the test in https://trac.webkit.org/r242730 in an effort to speed up ios-sim EWS.

[Ryan Haddad]

Perhaps this can be duped to https://bugs.webkit.org/show_bug.cgi?id=191707

[Shawn Roberts]

*** This bug has been marked as a duplicate of bug 191707 ***