I was correct that I had inadvertently installed a 32-bit version. I did not know that it was possible to install a 32-bit version on a 64-bit computer.
Anyway, using a 64-bit version of ubuntu 12.04, the bug exists in the newer kernel (3.5.0-23) too. # uname -a Linux michael-MS-7596 3.5.0-23-generic #35~precise1-Ubuntu SMP Fri Jan 25 17:13:26 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux And after the system crash, the relevant lines are: # grep test1 /var/log/syslog Apr 4 17:50:33 michael-MS-7596 kernel: [ 1664.381910] test1: Corrupted page table at address 7f44ec76f000 Apr 4 17:50:33 michael-MS-7596 kernel: [ 1664.383402] Pid: 3448, comm: test1 Not tainted 3.5.0-23-generic #35~precise1-Ubuntu MICRO-STAR INTERNATIONAL CO.,LTD MS-7596/760GM-E51(MS-7596) Apr 4 17:50:33 michael-MS-7596 kernel: [ 1664.384897] Process test1 (pid: 3448, threadinfo ffff8800c29a8000, task ffff8800c2c31700) I should add that although the program xawtv runs and does not crash the computer, the displayed video is partially corrupted. An excerpt of the program "test1.c" is below: ... //---------------------------------------- open /dev/mem fd_mem = open ("/dev/mem", O_RDWR | O_SYNC); if (fd_mem < 0) { fprintf (stderr, "failed opening \"/dev/mem\" (must run as root)\n"); exit (-1); } //----------------------------- initialize all Bt878 video inputs n_bt = 0; for (i = 0; i < 1; i++) { //----------------- read BT878 PCI configuration space (I/O space) sprintf (s, "/sys/class/video4linux/video%d/device/config", i); fp = fopen (s, "r"); if (fp == NULL) continue; fseek (fp, 0x00, SEEK_SET); // Vendor ID/Device ID fread (&j, 1, 4, fp); if (j != 0x036E109E) { // not Bt878 fclose (fp); continue; } fseek (fp, 0x10, SEEK_SET); // Base Address Register 0 (memory space registers) fread (&j, 1, 4, fp); j &= 0xFFFFF000; // The low BAR bits have special functions! fclose (fp); //------------------------ mmap memory space registers addr = (off_t) j; // The low BAR bits have special functions! memsize = 4096; mem = mmap (0, memsize, PROT_READ | PROT_WRITE, MAP_SHARED, fd_mem, addr); if (mem == MAP_FAILED) { perror ("mmap"); continue; } //-------------- The computer crashes at the following memcpy line. memcpy (&c, mem, 1); // DSTATUS if ((0x80 & c) == 0) { fprintf (stderr, "No video signal \"/dev/video%d\"\n", i); } //----------- open "/dev/video<i>" sprintf (s1, "/dev/video%d", i); fd = open (s1, O_RDWR); if (fd < 0) { fprintf (stderr, "open video failed"); munmap (mem, memsize); continue; } ... -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1162555 Title: repeatable system crash related to bttv kernel module To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1162555/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs