On 14.06.2013 19:05, Greg Kroah-Hartman wrote: > On Fri, Jun 14, 2013 at 04:38:03PM +0300, Jussi Kivilinna wrote: >> Appearently some out-of-tree USB host drivers do not handle DMA alignment for >> URB buffers and let core/hcd.c to do the mapping on architectures that have >> minimum DMA alignment requirements. This leads to random memory corruptions >> and crashes when using USB device drivers that use unaligned URB buffers. >> >> Instead of fixing host drivers, users end up posting bug reports against >> those USB device drivers that use unaligned buffers for URB; such as with >> rtl8192cu (http://thread.gmane.org/gmane.linux.kernel.wireless.general/105631). >> >> Patch makes this issue more visible at core level, and hopefully gives hint >> for future hcd driver implementors about this problem. > > You should be more forceful in your warning messages to blame the host > controller, as it is, if I was a user and I saw: > >> + WARN_ONCE(1, "urb->setup_packet not DMA aligned.\n"); > > I would think that the device driver was still the problem, not the host > controller. Ok. Would this be better? "Possibly broken USB host controller driver; does not correctly handle DMA alignment for urb->blabla.\n" ... or should that 'Possibly' be dropped and just say "broken USB ...". -Jussi > > thanks, > > greg k-h > -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
