On Fri, 28 Jul 2006 16:29:57 -0400 (EDT), Alan Stern <[EMAIL PROTECTED]> wrote:
> usbmon crashed when I tried using it with dummy-hcd, because it doesn't > check whether the bus's controller actually does use DMA before trying to > map the buffer. This patch (as755) fixes it. Ewww. This fixes the immediate problem, but not completely, IMHO. The problem arises because hcd_buffer_alloc (or any other implementation of bus->op->buffer_alloc) does not return any indication if they actually allocated the buffer with dma_buffer_alloc or kmalloc. Zero DMA handle is valid on some platforms. Therefore, your fix replicates the test made inside hcd_buffer_alloc. But if anyone ever overrides it, we risk of getting it wrong again. Why do we even have this bus operation method? -- Pete ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys -- and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
