Re: [Crash-utility] The problems when running SuSE 12 on VirtualBox

Hi David & Dave, Executing "crash" on a physical machine (not VirtualBox): # crash crash 7.1.3 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. crash: /boot/xen-4.5.gz: original filename unknown Use "-f /boot/xen-4.5.gz" on command line to prevent this message. WARNING: machine type mismatch: crash utility: X86_64 /var/tmp/xen-4.5.gz_VIOmfp: X86 crash: /boot/symtypes-3.12.49-6-default.gz: original filename unknown Use "-f /boot/symtypes-3.12.49-6-default.gz" on command line to prevent this message. crash: /boot/symvers-3.12.49-6-default.gz: original filename unknown Use "-f /boot/symvers-3.12.49-6-default.gz" on command line to prevent this message. 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 "x86_64-unknown-linux-gnu"... crash: this kernel may be configured with CONFIG_STRICT_DEVMEM, which renders /dev/mem unusable as a live memory source. crash: trying /proc/kcore as an alternative to /dev/mem KERNEL: /boot/vmlinux-3.12.49-6-xen.gz DEBUGINFO: /usr/lib/debug/boot/vmlinux-3.12.49-6-xen.debug DUMPFILE: /proc/kcore CPUS: 128 DATE: Thu Nov 19 09:37:49 2015 UPTIME: 00:34:57 LOAD AVERAGE: 1.77, 1.21, 1.02 TASKS: 1328 NODENAME: dl980-5 RELEASE: 3.12.49-6-xen VERSION: #1 SMP Mon Oct 26 16:05:37 UTC 2015 (11560c3) MACHINE: x86_64 (1995 Mhz) MEMORY: 125.9 GB PID: 39777 COMMAND: "crash" TASK: ffff881eacaaa100 [THREAD_INFO: ffff881e8ff46000] CPU: 3 STATE: TASK_RUNNING (ACTIVE) crash> I can see the crash will use "/proc/kcore" instead of "/dev/mem". So I try the same thing on VirtualBox: # crash /boot/vmlinux-3.12.49-6-xen.gz /proc/kcore crash 7.1.3 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 "x86_64-unknown-linux-gnu"... KERNEL: /boot/vmlinux-3.12.49-6-xen.gz DEBUGINFO: /usr/lib/debug/boot/vmlinux-3.12.49-6-xen.debug DUMPFILE: /proc/kcore CPUS: 1 DATE: Thu Nov 19 01:53:01 2015 UPTIME: 05:42:13 LOAD AVERAGE: 0.19, 0.06, 0.06 TASKS: 239 NODENAME: linux-6ev3 RELEASE: 3.12.49-6-xen VERSION: #1 SMP Mon Oct 26 16:05:37 UTC 2015 (11560c3) MACHINE: x86_64 (2594 Mhz) MEMORY: 855.2 MB PID: 3106 COMMAND: "crash" TASK: ffff88002ec5c040 [THREAD_INFO: ffff88000b3e2000] CPU: 0 STATE: TASK_RUNNING (ACTIVE) crash> It seems OK now. So my questions are: (1) Is it OK to use "/proc/kcore" instead of "/dev/mem" as a workaround? Is there any side-effect? (2) Execute "crash -d8" on physical machine will cause crash utility core dump. Use gdb to debug it: # gdb /usr/bin/crash core-crash-11-0-0-40072-1447945769 GNU gdb (GDB; SUSE Linux Enterprise 12) 7.9.1 Copyright (C) 2015 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 "x86_64-suse-linux". Type "show configuration" for configuration details. For bug reporting instructions, please see: <http://bugs.opensuse.org/>;. Find the GDB manual and other documentation resources online at: <http://www.gnu.org/software/gdb/documentation/>;. For help, type "help". Type "apropos word" to search for commands related to "word"... Reading symbols from /usr/bin/crash...Reading symbols from /usr/lib/debug/usr/bin/crash.debug...done. done. [New LWP 40072] Core was generated by `crash -d8'. Program terminated with signal SIGSEGV, Segmentation fault. #0 0x00007f5119001fd0 in get_cie_encoding (cie=0x7f5119004cd8) at ../../../libgcc/unwind-dw2-fde.c:272 272 ../../../libgcc/unwind-dw2-fde.c: No such file or directory. (gdb) (gdb) bt #0 0x00007f5119001fd0 in get_cie_encoding (cie=0x7f5119004cd8) at ../../../libgcc/unwind-dw2-fde.c:272 #1 0x00007f5119002699 in get_fde_encoding (f=0x7f5119006050) at ../../../libgcc/unwind-dw2-fde.c:319 #2 _Unwind_IteratePhdrCallback (info=info@entry=0x7fff463c10e0, size=size@entry=64, ptr=ptr@entry=0x7fff463c1160) at ../../../libgcc/unwind-dw2-fde-dip.c:408 #3 0x00007f51196a3f3c in __GI___dl_iterate_phdr (callback=callback@entry=0x7f5119002270 <_Unwind_IteratePhdrCallback>, data=data@entry=0x7fff463c1160) at dl-iteratephdr.c:76 #4 0x00007f51190035c3 in _Unwind_Find_FDE (pc=0x7f5119001aa7 <_Unwind_Backtrace+55>, bases=bases@entry=0x7fff463c1498) at ../../../libgcc/unwind-dw2-fde-dip.c:459 #5 0x00007f5118ffff86 in uw_frame_state_for (context=context@entry=0x7fff463c13f0, fs=fs@entry=0x7fff463c1240) at ../../../libgcc/unwind-dw2.c:1241 #6 0x00007f51190011d0 in uw_init_context_1 (context=context@entry=0x7fff463c13f0, outer_cfa=outer_cfa@entry=0x7fff463c16a0, outer_ra=0x7f511967bf46 <__GI___backtrace+86>) at ../../../libgcc/unwind-dw2.c:1562 #7 0x00007f5119001aa8 in _Unwind_Backtrace (trace=0x7f511967bdd0 <backtrace_helper>, trace_argument=0x7fff463c16a0) at ../../../libgcc/unwind.inc:283 #8 0x00007f511967bf46 in __GI___backtrace (array=array@entry=0x7fff463c1710, size=size@entry=4) at ../sysdeps/x86_64/backtrace.c:109 #9 0x000000000047add7 in __error (type=type@entry=1, fmt=fmt@entry=0x853d38 "read(/dev/mem, %lx, %ld): %ld (%lx)\n") at tools.c:52 #10 0x0000000000490c91 in read_dev_mem (fd=4, bufptr=0x7fff463c1f28, cnt=8, addr=0, paddr=1052672) at memory.c:2298 #11 0x0000000000486398 in readmem (addr=1052672, memtype=memtype@entry=4, buffer=buffer@entry=0x7fff463c1f28, size=size@entry=8, type=type@entry=0x8563e1 "devmem_is_allowed - pfn 257", error_handle=error_handle@entry=6) at memory.c:2198 #12 0x000000000048704a in devmem_is_restricted () at memory.c:2414 #13 readmem (addr=1052672, memtype=memtype@entry=4, buffer=buffer@entry=0x7fff463c1fb8, size=size@entry=8, type=type@entry=0x8563e1 "devmem_is_allowed - pfn 257", error_handle=error_handle@entry=6) at memory.c:2209 #14 0x000000000048704a in devmem_is_restricted () at memory.c:2414 #15 readmem (addr=1052672, memtype=memtype@entry=4, buffer=buffer@entry=0x7fff463c2048, size=size@entry=8, type=type@entry=0x8563e1 "devmem_is_allowed - pfn 257", error_handle=error_handle@entry=6) at memory.c:2209 #16 0x000000000048704a in devmem_is_restricted () at memory.c:2414 #17 readmem (addr=1052672, memtype=memtype@entry=4, buffer=buffer@entry=0x7fff463c20d8, size=size@entry=8, type=type@entry=0x8563e1 "devmem_is_allowed - pfn 257", error_handle=error_handle@entry=6) at memory.c:2209 #18 0x000000000048704a in devmem_is_restricted () at memory.c:2414 #19 readmem (addr=1052672, memtype=memtype@entry=4, buffer=buffer@entry=0x7fff463c2168, size=size@entry=8, type=type@entry=0x8563e1 "devmem_is_allowed - pfn 257", error_handle=error_handle@entry=6) at memory.c:2209 #20 0x000000000048704a in devmem_is_restricted () at memory.c:2414 #21 readmem (addr=1052672, memtype=memtype@entry=4, buffer=buffer@entry=0x7fff463c21f8, size=size@entry=8, type=type@entry=0x8563e1 "devmem_is_allowed - pfn 257", error_handle=error_handle@entry=6) at memory.c:2209 #22 0x000000000048704a in devmem_is_restricted () at memory.c:2414 #23 readmem (addr=1052672, memtype=memtype@entry=4, buffer=buffer@entry=0x7fff463c2288, size=size@entry=8, type=type@entry=0x8563e1 "devmem_is_allowed - pfn 257", error_handle=error_handle@entry=6) at memory.c:2209 #24 0x000000000048704a in devmem_is_restricted () at memory.c:2414 ...... Below is always: readmem (addr=1052672, memtype=memtype@entry=4, buffer=buffer@entry=0x7fff463c2288, size=size@entry=8, type=type@entry=0x8563e1 "devmem_is_allowed - pfn 257", error_handle=error_handle@entry=6) at memory.c:2209 0x000000000048704a in devmem_is_restricted () at memory.c:2414 Seems a dead-loop, but not sure. Thanks! Best Regards Nan Xiao On Thu, Nov 19, 2015 at 1:51 AM, David Mair <dmair(a)suse.com&gt; wrote: