From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from wproxy.gmail.com (wproxy.gmail.com [64.233.184.239]) by ozlabs.org (Postfix) with ESMTP id EE9BF67A5A for ; Mon, 17 Apr 2006 21:35:35 +1000 (EST) Received: by wproxy.gmail.com with SMTP id 71so419821wri for ; Mon, 17 Apr 2006 04:35:33 -0700 (PDT) Message-ID: <460643480604170435m5f0c27efmab8326234c69e9e2@mail.gmail.com> Date: Mon, 17 Apr 2006 17:05:33 +0530 From: "Akshay Mishra" To: linuxppc-embedded@ozlabs.org Subject: Re: kernel access of bad area, sig: 11 ( mpc852t) MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , >> Hi, >> Im having problem porting linux kernel 2.4.21 to our mpc852T custom >> board.The kernel >> panics randomly with sig 11. >> The board boots up fine and we also get to the prompt.When we open 3-4 >> telnet sessions >> and try to run some command the kernel panics.This is completely >> random.Sometimes it >> even panics before opening the telnet session. >> >> One of the oops dump is: >> >> ------------------------------------------------------------------------= ------------ \ >> ----------------------------------------- >> Oops: kernel access of bad area, sig: 11 >> NIP: C0019FD0 XER: 00000000 LR: C001A06C SP: C1C33AD0 REGS: c1c33a20 >> TRAP: 0300 Not tainted >> MSR: 00009032 EE: 1 PR: 0 FP: 0 ME: 1 IR/DR: 11 >> DAR: 725F6578, DSISR: 0000000B >> TASK =3D c1c32000[48] 'insmod' Last syscall: 5 >> last math 00000000 last altivec 00000000 >> GPR00: 7361726D C1C33AD0 C1C32000 00000000 C0113678 C0150000 C0150000 >> C014B210 >> GPR08: C014B210 C012D060 00000000 725F6578 04000024 00000000 00000000 >> 00000000 >> GPR16: 00000000 00000000 00000000 00000000 00001032 01C33BA0 00000000 >> C0000000 >> GPR24: C014BE38 C0150000 C0110000 C0110000 C0140000 00000001 00000000 >> 00000001 >> Call backtrace: >> C001A0C8 C0016174 C0015FEC C0015CC0 C0005E38 C0004668 C1C33D10 >> C0004670 C004A380 C003FFD4 C00404D8 C0040AD4 C0040FF8 C00330D8 >> C00334AC C000443C 1006EF48 1001FCF0 1002023C 10003A18 100036A0 >> 300591AC 00000000 >> ------------------------------------------------------------------------= ------------ \ >> ----------------------------------------- >> The call trace back is of not much help because it is different on all >> oops. >> We are using u-boot 1-1-3. >> >> Thanks in advance. >> >You almost certainly have SDRAM problems. If you have thoroughly checked >out the >complete address range statically, remember that burst accesses will not >occur until the >cache is turned on, so your problem may be with bursting. But you can als= o >have severe >problems like a missing address line and linux still run for a few seconds= . > >Mark Chambers We've checked the SDRAM. The timings (UPM) look fine. The problem however is that linux does not hang until after a few processes are started. If we boot to linux and leave it as it is, everything is fine and the board remains working. However each time a few processes (4-5 telnet sessions for eg.) are started the system either panics or hangs (goes dead). Thanks in advance, Akshay