Il 02/02/2012 20:07, Devin Heitmueller ha scritto: > On Thu, Feb 2, 2012 at 2:02 PM, Gianluca Gennari <gennarone@xxxxxxxxx> wrote: >> I'm trying to reproduce the problem with another em28xx-dvb device to >> see if it is not restricted to the PCTV 290e. Before the PCTV 290e, I >> was using a different device with a driver based on the dvb-usb >> framework, and I never observed similar crashes. > > On ARM based platforms it is very likely you will run into this issue > with most USB based tuners. It's because over time there is memory > fragmentation that occurs which prevents being able to allocate large > enough chunks of coherent memory. > > Making such a scenario work would require hacks to the driver code to > preallocate the memory in some form of static pool at system boot (or > perhaps at driver initialization), and then reuse that memory instead > of attempting to allocate it as needed. > > Devin > Hi Devin, thanks for the explanation. The CPU is MIPS based (not ARM) but I guess there is not much of a difference from this point of view. As I mentioned in my first reply, I never had this kind of errors when I was using a dvb-usb USB stick. Now I'm trying to replicate the problem with a Terratec Hybrid XS (em28xx-dvb + zl10353 + xc2028), and so far I've stressed it for a few hours without problems. We will see in a day or two if I can make it fail in the same way. Regards, Gianluca -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
