Hi Anoop... I know nothing about MIPS, but perhaps I could share general ideas here.... On Sat, Mar 6, 2010 at 4:28 PM, Anoop <anoop.chargotra@xxxxxxxxx> wrote: > Hi List, > > I am working on a target with MIPS architecture to support a USB 3G > card. This card uses 'option' usb serial driver. > Every thing goes fine, until I plug out the card when connection is up. Uhm, what does that mean? you unplug the card while the connection is still established? What are you trying to achieve here, bug testing maybe? > It throws up a dump on the console and after that USB subsystem doesn't work. > > I am using Kernel '2.6.21'. > > Any help in this regard will be highly appreciated. > > Thanks, > Anoop > > Here is the dump: > > [...] > > Unhandled kernel unaligned access[#1]: I have a guess, that MIPS is one of the architectures that forbid unaligned memory access i.e it will throws exception when we access memory address which is not a multiple of bus width (CMIIW). Thus, my blind guess, there is no installed exception handler that handle this unaligned access...hence the bug is showing (in other word, "standart action" is executed....stack dump and sometimes kernel panic...depending on the situation). perhaps what you also should check is that to make sure all the memory allocation you do is properly aligned.... -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ