Hi there, Sorry to send this email again. My previous email was rejected by email system because it only accepts TEXT/PLAIN content. We use 5.10 LTS kernel with RT patches, but recently we encounter an issue. When we playing a H265 file on our Tiger Lake platform (OS : Yocto, CPU : Intel® CoreT i7-1185GRE Processor (12M Cache, up to 4.40 GHz)), we encounter a system hang/freeze issue (without enabling GuC submitting) We use the following command to reproduce this issue. gst-launch-1.0 filesrc location=/mnt/media/Duck_3840x2160_10mbps_25fps_Main_at_L5.0.mkv ! matroskademux ! h265parse ! msdkh265dec ! msdkvpp ! 'video/x-raw(memory:DMABuf),width=3840,height=2160' ! glimagesink We also can reproduce this issue on upstream v5.15.27-rt35. The dmesg log from UART port. After the log showed "the sched: RT throttling activated", the screen freeze. After bisecting, we found that it was related to the following patchset https://lkml.org/lkml/2021/10/6/367 If we revert this patchset, we cannot reproduce this issue. And we also found that If we revert the following patch without touching the RT patches. We cannot reproduce this issue, either, https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v5.17&id=2b2985a417c7ca1752a4f0b2631cf916dabd43b5 but this DRM patch was merged into kernel mainline a long time ago. You are the RT kernel expert. Maybe you can help investigate this issue. P.S. Our RT patches are always from https://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git DRM patches are from upstream community kernel Best Regards, Angus
