EDIT: Description has been rewritten as the initial test case was incorrect. Waypipe (package, workaround) relies on DMA_BUF_IOCTL_SYNC to check if a given file descripter is backed by DMABUF. On FreeBSD the ioctl always fails with EBADF...
@@ -352,7 +352,8 @@ Being able to mmap an export dma-buf buffer object has 2 main use-cases: No special interfaces, userspace simply calls mmap on the dma-buf fd, making sure that the cache synchronization ioctl (DMA_BUF_IOCTL_SYNC) is *always* used when the access happens. This...
llvmpipe seems to require this ioctl under normal operation, which makes it hard to use rr to debug an application that uses OpenGL to render its UI (e.g. something written in Qt Quick). Tested with rr 5.8.0 built from commit 946378b. Ba...