Hi, I'm having a problem getting SIGSEGV in a multi (posix)-threaded process (let me refer to that process with P1) running on a TQM board (TQM855LDBBA3-T66.204) under a patched kernel provided by DENX (linux-2.4.4-2002_03_21). In addition to the patched kernel rtai-24.1.8-2002-03-21 (also provided by DENX) is running. The libraries I use are the ones indicated by LIB_LIST_HH-2.0 under SELF-2002-03-21. The MPC855 is running with data caches disabled.
Debugging of the generated core file (backtracing via gdb's "bt") shows that the last thread running in process P1 was blocking in a nanosleep() system call at that time. To retrieve a little bit more information (PID, memory address) I patched the kernel fault handler (fault.c) to see what memory reference causes the SIGSEGV. It seems like the faulty address is deterministically the same (0x5). I currently assume (please correct me if my assumption might be wrong) that this crash is not directly caused by one of the (posix-)threads running in P1 for the following reasons: - Substitution of the nanosleep() system call with a select(0,0,0,0,&timeval) system call in the indicated thread also leads to the very same problem with the very same address (0x5). - After moving the code being executed by the indicated thread into a dedicated different PROCESS P2 another thread of P1 crashes with the same SISEGV (and the same memory address 0x5 also blocking in a select() system call). Is there anything else I can give a try in user space ? Has anybody successfully run kdb on that platform ? If yes is there anything special I have to consider in setting up kdb on a TQM855 board? I appreciate any hints. Please forgive me in case I should be able to find answers to those questions somewhere (in case those questions are standard questions). I think I spent a reasonable amount of time crawling in KHG, this mailing list' archive and the like, but I'm simply running out of time. Thanks, Christian ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
