Is there anyone else find the same problem? I download the gdb/insight 5.3 , want to use it to debug my mipsel idt334 board. configure as --target=mipsel-linux. when connect to the target , it always give me some wrong addr: new thead xxxxxx 0xffffffff83f28040 in ??() something like that. and the backtrace command can't work, also. but my gdb5.0 for mipsel is ok. I think that's the gdb get the pc as 64bit, but my board's cpu is 32bit, so it can't get the correct pc ... The kernel addr is up to 0x80000000, so it's negative. I trace the gdb5.3 , and find the place in mips-tdep.c, so I just fix the read_pc , make it as 32bit , now it can work, and the backtrace command can display the call trace . But I'm not sure if my fix is a full one ? Anyone have full patch please tell me ... renc