Graphics programming • drmModeAtomicCommit leaves terminated process frame buffer

Ran into a situation where a child process using drmModeAtomicCommit() terminates unexpectedly but its most recently displayed framebuffer remains visible if the parent process is also using drmModeAtomicCommit(). If the parent process uses drmModePageFlip(), then the child framebuffer is removed as expected. Presumably if a subsequent process allocated memory overlapping the old framebuffer (which comes from either "/dev/dma_heap/system" or "/dev/dma_heap/linux,cma"), that data would be visualized by the HVS until some process resets the display list. Have run into this issue on both Pi4 & Pi5 under bookworm.

Question-- Is VC4 supposed to recognize a framebuffer has been freed and remove it from the display-list?

Statistics: Posted by Vraz — Sun Dec 22, 2024 10:38 pm

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