Hello, I just noticed that on ppc64le, sometimes "bt" cannot find the stack info of current process. For example, there is a vmcore captured by kdump on a ppc64le system, which running with a kernel version 3.10. The vmcore was captured when kernel oopsed. There is no stack info found by bt: crash 7.0.9-2.ael7b Copyright (C) 2002-2014 Red Hat, Inc. Copyright (C) 2004, 2005, 2006, 2010 IBM Corporation Copyright (C) 1999-2006 Hewlett-Packard Co Copyright (C) 2005, 2006, 2011, 2012 Fujitsu Limited Copyright (C) 2006, 2007 VA Linux Systems Japan K.K. Copyright (C) 2005, 2011 NEC Corporation Copyright (C) 1999, 2002, 2007 Silicon Graphics, Inc. Copyright (C) 1999, 2000, 2001, 2002 Mission Critical Linux, Inc. This program is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Enter "help copying" to see the conditions. This program has absolutely no warranty. Enter "help warranty" for details. GNU gdb (GDB) 7.6 Copyright (C) 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "powerpc64le-unknown-linux-gnu"... KERNEL: /usr/lib/debug/lib/modules/3.10.0-221.ael7b.ppc64le/vmlinux DUMPFILE: /var/crash/127.0.0.1-2015.01.15-22:19:14/vmcore [PARTIAL DUMP] CPUS: 16 DATE: Thu Jan 15 21:18:16 2015 UPTIME: 17:53:43 LOAD AVERAGE: 213.58, 213.23, 212.70 TASKS: 1383 NODENAME: thymelp2.isst.aus.stglabs.ibm.com RELEASE: 3.10.0-221.ael7b.ppc64le VERSION: #1 SMP Wed Jan 7 09:27:09 EST 2015 MACHINE: ppc64le (3425 Mhz) MEMORY: 15 GB PANIC: "Oops: Kernel access of bad area, sig: 11 [#1]" (check log for details) PID: 1970 COMMAND: "cat" TASK: c0000003130874a0 [THREAD_INFO: c00000005069c000] CPU: 5 STATE: TASK_RUNNING (PANIC) crash> set debug 99 debug: 99 crash> bt PID: 1970 TASK: c0000003130874a0 CPU: 5 COMMAND: "cat" GETBUF(16384 -> 0) <readmem: c00000005069c000, KVADDR, "stack contents", 16384, (ROE), 10a81570> <read_diskdump: addr: c00000005069c000 paddr: 5069c000 cnt: 16384> read_diskdump: paddr/pfn: 5069c000/5069 -> cache physical page: 50690000 c00000005069c018: do_no_restart_syscall c00000005069e870: blk_throtl_bio+240 c00000005069e990: clone_endio c00000005069ea00: generic_make_request_checks+836 c00000005069eab8: hardware_interrupt_common+128 c00000005069eac0: generic_make_request+36 c00000005069eb10: mempool_alloc_slab+36 c00000005069eb30: mempool_alloc+256 c00000005069eb50: mempool_alloc_slab+36 c00000005069ebc0: get_request+948 c00000005069ec00: __split_and_process_bio+1408 c00000005069ec20: autoremove_wake_function c00000005069ec80: find_busiest_group+544 c00000005069edf0: load_balance+684 c00000005069ee10: blk_throtl_bio+240 c00000005069ee70: find_busiest_group+544 c00000005069eee0: dequeue_task_fair+968 c00000005069ef30: clone_endio c00000005069ef50: get_page_from_freelist+1436 c00000005069f0a0: pSeries_cause_ipi_mux+112 c00000005069f0c0: smp_send_reschedule+164 c00000005069f0e0: default_wake_function+708 c00000005069f160: __wake_up_locked+116 c00000005069f1b0: ep_poll_callback+444 c00000005069f250: run_posix_cpu_timers+104 c00000005069f2c0: hvterm_raw_put_chars+64 c00000005069f2e0: hvc_console_print+336 c00000005069f3a8: initial_stab+2048 c00000005069f3b0: crash_save_cpu+252 c00000005069f488: cik_cp_resume+13476 c00000005069f490: dev_get_drvdata c00000005069f580: default_machine_kexec+332 c00000005069f610: pSeries_machine_kexec+60 c00000005069f680: machine_kexec+56 c00000005069f6a0: crash_kexec+312 c00000005069f6f0: dev_attr_show+64 c00000005069f748: cik_cp_resume+13476 c00000005069f750: dev_get_drvdata c00000005069f7f0: radeon_hwmon_show_temp+72 c00000005069f800: slb_miss_realmode+80 c00000005069f808: dev_get_drvdata c00000005069f810: radeon_hwmon_show_temp+32 c00000005069f890: die+840 c00000005069f930: bad_page_fault+224 c00000005069f948: radeon_hwmon_show_temp+72 c00000005069f9a0: handle_page_fault+44 c00000005069fa00: dev_attr_show+64 c00000005069fa58: cik_cp_resume+13476 c00000005069fa60: dev_get_drvdata c00000005069fb00: radeon_hwmon_show_temp+72 c00000005069fb10: slb_miss_realmode+80 c00000005069fb18: dev_get_drvdata c00000005069fb20: radeon_hwmon_show_temp+32 c00000005069fb60: handle_mm_fault+1724 c00000005069fb80: sysfs_open_file c00000005069fbd0: handle_page_fault+16 c00000005069fc90: alloc_pages_current+416 c00000005069fd00: dev_attr_show+64 c00000005069fd30: sysfs_read_file+220 c00000005069fde0: sys_read+304 c00000005069fe40: syscall_exit [3fffd0d6fe88] back_trace: task: c0000003130874a0 flags: 0 instptr: 0 stkptr: 0 bptr: 0 stackbase: c00000005069c000 stacktop: c0000000506a0000 tc: 1003c7b9fa8 (1970, c0000003130874a0) hp: 0 ref: 0 stackbuf: 10a81570 textlist: 0 frameptr: 0 call_target: none eframe_ip: 0 debug: 0 radix: 0 cpumask: 0 => PC: 0 () FP: 0 GETBUF(248 -> 1) GETBUF(1500 -> 2) cannot find the stack info. FREEBUF(2) FREEBUF(1) crash> Is this a problem? Thanks in advance! -- Crash-utility mailing list Crash-utility@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/crash-utility