# SIGSEGV from nvcompositor (pp\_vic:src) during repeated PLAYING→NULL→PLhttps://forums.developer.nvidia.com/t/gst-launch-1AYING cycles on Jetson Orin NX **URL:** \ **Category:** Jetson Orin NX\ **Tags:** gstreamer\ **Created:** [May 25, 2026, 5:22am UTC](https://forums.developer.nvidia.com/t/sigsegv-from-nvcompositor-pp-vic-src-during-repeated-playing-null-plhttps-forums-developer-nvidia-com-t-gst-launch-1aying-cycles-on-jetson-orin-nx/371236 "2026-05-25T05:22:27Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![muthu270405](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@muthu270405](https://forums.developer.nvidia.com/u/muthu270405)\ **Post date:** [May 25, 2026, 5:22am UTC](https://forums.developer.nvidia.com/t/sigsegv-from-nvcompositor-pp-vic-src-during-repeated-playing-null-plhttps-forums-developer-nvidia-com-t-gst-launch-1aying-cycles-on-jetson-orin-nx/371236/1 "2026-05-25T05:22:27Z")
# I am debugging a recurring segmentation fault from `nvcompositor` on a Jetson Orin NX. ## Environment - Device: NVIDIA Jetson Orin NX 16GB - Pipeline uses NVMM / VIC / `nvv4l2h264enc` * * * # Problem The pipeline works correctly during the first iteration. After: - EOS - PLAYING → NULL - PLAYING again I eventually get: ```auto Thread 71 "pp_vic:src" received signal SIGSEGV 0x0000ffffd4474ee8 in ?? from /usr/lib/aarch64-linux-gnu/gstreamer-1.0/libgstnvcompositor.so ``` The crash consistently occurs from: ```auto pp_vic:src ``` which appears to be the `nvcompositor` streaming thread. * * * # Pipeline structure ## Video branch ```auto filesrc -> decodebin -> nvvideoconvert -> capsfilter(memory:NVMM) -> queue -> nvcompositor sink_0 ``` ## Overlay branch ```auto videotestsrc -> capsfilter -> videoconvert -> cairooverlay -> nvvideoconvert -> capsfilter(memory:NVMM) -> queue -> nvcompositor sink_1 ``` The overlay is stitched below the main video. ## Main processing branch ```auto nvcompositor -> nvvideoconvert -> capsfilter -> nvvideoconvert -> capsfilter(NV12) -> nvv4l2h264enc -> queue -> h264parse -> mp4mux -> filesink ``` * * * # Main loop The pipeline is initialized only once. Each iteration does: ```auto gst_element_set_state(pipeline, GST_STATE_READY); gst_element_set_state(pipeline, GST_STATE_PAUSED); gst_element_set_state(pipeline, GST_STATE_PLAYING); wait_for_eos(); gst_element_set_state(pipeline, GST_STATE_NULL); ``` Then the next iteration starts again. * * * # Important details - Uses request pads on `nvcompositor` - Request pads are released during destroy - `flush-on-eos=TRUE` on queues - NVMM caps everywhere before compositor - `videotestsrc` is configured with: * * * # Suspected issue I suspect one of: - VIC thread still active during NULL transition - `nvcompositor` internal race - EOS synchronization issue between overlay/video branches I also noticed: ```auto NvVideo: bBlitMode is set to TRUE ``` before the crash. * * * # Questions 1. Is `nvcompositor` known to have teardown races across repeated PLAYING-\>NULL cycles on Jetson? 2. Is `videotestsrc` problematic inside an Aggregator pipeline? 3. Is there a recommended teardown order for: 4. Should the pipeline instead be fully recreated each iteration rather than reused? GDB debug output : ```auto Post processing has been started .... Starting iteration 0 Opening in BLOCKING MODE [New Thread 0xffffed0aee60 (LWP 26712)] [New Thread 0xffffec863e60 (LWP 26713)] [New Thread 0xffffdfffee60 (LWP 26714)] [New Thread 0xffffdf7eee60 (LWP 26715)] [New Thread 0xffffdefdee60 (LWP 26716)] [New Thread 0xffffde7cee60 (LWP 26717)] [New Thread 0xffffddfbee60 (LWP 26718)] [New Thread 0xffffdd47ee60 (LWP 26719)] [New Thread 0xffffdcc3fe60 (LWP 26720)] Opening in BLOCKING MODE NvMMLiteOpen : Block : BlockType = 261 [New Thread 0xffffb99f5e60 (LWP 26721)] [New Thread 0xffffb91e5e60 (LWP 26722)] [New Thread 0xffffb89d5e60 (LWP 26723)] NvMMLiteBlockCreate : Block : BlockType = 261 [New Thread 0xffffb81c5e60 (LWP 26724)] [New Thread 0xffffb61bfe60 (LWP 26725)] Linked lOvCamPPDecodebin pad to capsPad [New Thread 0xffffb5149e60 (LWP 26726)] NvMMLiteOpen : Block : BlockType = 4 ===== NvVideo: NVENC ===== NvMMLiteBlockCreate : Block : BlockType = 4 [New Thread 0xffff89a1ee60 (LWP 26727)] [New Thread 0xffff8920ee60 (LWP 26728)] H264: Profile = 66 Level = 0 [New Thread 0xffff81608e60 (LWP 26729)] [New Thread 0xffff80df8e60 (LWP 26730)] NVMEDIA: Need to set EMC bandwidth : 2872000 NvVideo: bBlitMode is set to TRUE [Thread 0xffffb81c5e60 (LWP 26724) exited] [Thread 0xffff8920ee60 (LWP 26728) exited] EOS for: /app/VideoSamples/mk/GstreamerPipelineTest/OV_sampleviDeo_0.mp4 Elapsed time: 70.1156 seconds Post Processing completed for iteration 0 [Thread 0xffff89a1ee60 (LWP 26727) exited] Resetting pipeline for next iteration 0 [Thread 0xffffb89d5e60 (LWP 26723) exited] [Thread 0xffffb91e5e60 (LWP 26722) exited] [Thread 0xffffb99f5e60 (LWP 26721) exited] [Thread 0xffff80df8e60 (LWP 26730) exited] [Thread 0xffff81608e60 (LWP 26729) exited] [Thread 0xffffed0aee60 (LWP 26712) exited] [Thread 0xffffec863e60 (LWP 26713) exited] [Thread 0xffffdf7eee60 (LWP 26715) exited] [Thread 0xffffdefdee60 (LWP 26716) exited] [Thread 0xffffdfffee60 (LWP 26714) exited] [Thread 0xffffdcc3fe60 (LWP 26720) exited] [Thread 0xffffdd47ee60 (LWP 26719) exited] [Thread 0xffffddfbee60 (LWP 26718) exited] [Thread 0xffffde7cee60 (LWP 26717) exited] Re-initializing pipeline for next iteration 0 Starting iteration 1 Opening in BLOCKING MODE [New Thread 0xffffde7cee60 (LWP 26731)] [New Thread 0xffffddfbee60 (LWP 26732)] [New Thread 0xffffdd47ee60 (LWP 26733)] [New Thread 0xffffdcc3fe60 (LWP 26734)] [New Thread 0xffffed0aee60 (LWP 26735)] [New Thread 0xffffec89ee60 (LWP 26736)] [New Thread 0xffffdfffee60 (LWP 26737)] [New Thread 0xffffdf7eee60 (LWP 26738)] Opening in BLOCKING MODE NvMMLiteOpen : Block : BlockType = 261 [New Thread 0xffffb9ffee60 (LWP 26739)] [New Thread 0xffffb97eee60 (LWP 26740)] [New Thread 0xffffb8fdee60 (LWP 26741)] NvMMLiteBlockCreate : Block : BlockType = 261 [New Thread 0xffffb87cee60 (LWP 26742)] Linked lOvCamPPDecodebin pad to capsPad [New Thread 0xffffa7ffee60 (LWP 26743)] NvMMLiteOpen : Block : BlockType = 4 ===== NvVideo: NVENC ===== NvMMLiteBlockCreate : Block : BlockType = 4 Thread 24 "pp_vic:src" received signal SIGSEGV, Segmentation fault. [Switching to Thread 0xffffddfbee60 (LWP 26732)] 0x0000ffffee194ee8 in ?? () from /usr/lib/aarch64-linux-gnu/gstreamer-1.0/libgstnvcompositor.so (gdb) bt #0 0x0000ffffee194ee8 in () at /usr/lib/aarch64-linux-gnu/gstreamer-1.0/libgstnvcompositor.so #1 0x0000fffff593ee5c [PAC] in () at /usr/lib/aarch64-linux-gnu/libgstvideo-1.0.so.0 #2 0x0000fffff5b29038 in () at /usr/lib/aarch64-linux-gnu/libgstbase-1.0.so.0 #3 0x0000fffff7d2180c in () at /usr/lib/aarch64-linux-gnu/libgstreamer-1.0.so.0 #4 0x0000fffff7b08ab8 in g_thread_pool_thread_proxy (data=) at ../glib/gthreadpool.c:350 #5 0x0000fffff7b08064 in g_thread_proxy (data=0xffffe8000e40) at ../glib/gthread.c:831 #6 0x0000fffff75bd5c8 in () at /usr/lib/aarch64-linux-gnu/libc.so.6 #7 0x0000fffff7625edc in () at /usr/lib/aarch64-linux-gnu/libc.so.6 (gdb) ``` ![currentPPoptplying](https://global.discourse-cdn.com/nvidia/original/4X/7/9/f/79f4fa34be4faa94d7d7de3f5f115cb1a43619f9.png) Any debugging suggestions would help a lot — I’ve been stuck on this for weeks. for full code : [VICpipeline](https://codeshare.io/GstreamerProblem) ---
**Author:** ![DaneLLL](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/danelll/32/14043_2.png) [@DaneLLL](https://forums.developer.nvidia.com/u/DaneLLL)\ **Post date:** [May 25, 2026, 7:46am UTC](https://forums.developer.nvidia.com/t/sigsegv-from-nvcompositor-pp-vic-src-during-repeated-playing-null-plhttps-forums-developer-nvidia-com-t-gst-launch-1aying-cycles-on-jetson-orin-nx/371236/4 "2026-05-25T07:46:14Z")
Hi, Since _nvcompositor_ plugin is open source, please download the source code and add debug prints to check further. Please download the packge and follow README to build the plugin: > [Jetson Linux Release 36.5 | NVIDIA Developer](https://developer.nvidia.com/embedded/jetson-linux-r365) > Driver Package (BSP) Sources Please also try the sample commands in developer guide and see if the issue still appears: [Accelerated GStreamer — NVIDIA Jetson Linux Developer Guide](https://docs.nvidia.com/jetson/archives/r36.5/DeveloperGuide/SD/Multimedia/AcceleratedGstreamer.html#video-composition-with-gstreamer-1-0) ---
**Author:** ![muthu270405](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@muthu270405](https://forums.developer.nvidia.com/u/muthu270405)\ **Post date:** [May 25, 2026, 2:00pm UTC](https://forums.developer.nvidia.com/t/sigsegv-from-nvcompositor-pp-vic-src-during-repeated-playing-null-plhttps-forums-developer-nvidia-com-t-gst-launch-1aying-cycles-on-jetson-orin-nx/371236/5 "2026-05-25T14:00:06Z")
As i am running this entire pipeline inside the docker container (on deepstream:7.0-triton-multiarch) and i am construct and initialize the pipeline once And then i am reusing the pipeline by changing the src , sink locations and the piepline states. I think the Nvcompositor src thread holds the previous NVMM buffer memory eventhough I flush and cleanup the ncompositor before setting it to null. And the NVcompositor works fine for PLAYING → NULL → pipeline dies But it doesn’t work for Playing → NULL → Playing cycle And I have added some debug prints in the nvcompositor.c file and here they are ```auto GST_DEBUG_LOGS 0:00:11.208544416 5315 0xffff780010f0 WARN nvcompositor gstnvcompositor.c:1324:do_nvcomposite: About to NvBufSurfTransformMultiInputBufCompositeBlend, dst_surf=0xffff6c488db0 input_count=1 Flushed compositor sink_0 pad for next iteration 0 Flushed compositor sink_1 pad for next iteration 0 Flushed compositor pads for next iteration 0 EOS for: /app/VideoSamples/mk/GstreamerPipelineTest/OV_sampleviDeo_0.mp4 Elapsed time: 11.1127 seconds Post Processing completed for iteration 0 Resetting pipeline for next iteration 0 Flushed compositor sink_0 pad for next iteration 0 Flushed compositor sink_1 pad for next iteration 0 ^[[FFlushed compositor pads for next iteration 0 0:00:14.741151616 5315 0xaaaae0e691b0 WARN nvcompositor gstnvcompositor.c:1072:gst_nvcompositor_stop: nvcompositor STOP called — freeing pool=0xffff6c4856d0 0:00:14.741230912 5315 0xaaaae0e691b0 WARN nvcompositor gstnvcompositor.c:1079:gst_nvcompositor_stop: nvcompositor pool freed and NULL'd 0:00:14.741253280 5315 0xaaaae0e691b0 WARN nvcompositor gstnvcompositor.c:1083:gst_nvcompositor_stop: freeing comp_params: src_rect=0xaaaae0dff030 dst_rect=0xaaaae0dff140 alpha=0xaaaae0dff250 color_bg=0xaaaae0dff2a0 0:00:14.741267136 5315 0xaaaae0e691b0 WARN nvcompositor gstnvcompositor.c:1098:gst_nvcompositor_stop: nvcompositor STOP complete Starting iteration 1 NvMMLiteOpen : Block : BlockType = 261 NvMMLiteBlockCreate : Block : BlockType = 261 Opening in BLOCKING MODE Opening in BLOCKING MODE Linked lOvCamPPDecodebin pad to capsPad NvMMLiteOpen : Block : BlockType = 4 ===== NvVideo: NVENC ===== NvMMLiteBlockCreate : Block : BlockType = 4 0:00:16.034511808 5315 0xffff78000e40 WARN nvcompositor gstnvcompositor.c:913:gst_nvcompositor_negotiated_caps: Release old pool 0:00:16.034587968 5315 0xffff78000e40 WARN nvcompositor gstnvcompositor.c:916:gst_nvcompositor_negotiated_caps: negotiated_caps: out=3840x2260 fmt=19 — old pool released, decide_allocation will create new one ``` From this i have infered that the gst\_nvcompositor\_init() started when the pipeline is started do\_nvcomposite() → works fine during playing … When the pipeline goes NULL , gst\_nvcompositor\_stop() will execute and remove all the reference pointers. Here the crash occurs when i am again set the pipeline playing , init() will not execute and it directly calls the do\_nvcomposite() → it tries to access the NULL pointer causing the SIGSEG Fault. ---
**Author:** ![system](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/system/32/68080_2.png) [@system](https://forums.developer.nvidia.com/u/system)\ **Post date:** [July 8, 2026, 2:17am UTC](https://forums.developer.nvidia.com/t/sigsegv-from-nvcompositor-pp-vic-src-during-repeated-playing-null-plhttps-forums-developer-nvidia-com-t-gst-launch-1aying-cycles-on-jetson-orin-nx/371236/7 "2026-07-08T02:17:26Z")
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