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It was. > Comparatively, I still think my patch to be a more elegant solution, > and the original author also seems to share my thoughts. > > If my patch is unelegant, then what would be the elegant/state of the > art way to free all this DMA allocated memory? > (pointing to any reference driver implementation should be enough for > me to understand). I have two options to offer. 1. Use the existing URB_NO_TRANSFER_D;MA_MAP to decide how to free memory. 2. Provide an explicit API in usbcore among the anchor API =C2=A0=C2=A0=C2=A0 Regards =C2=A0=C2=A0=C2=A0 =C2=A0=C2=A0=C2=A0 Oliver