Bug 1223440 - crash fails to find MAGIC_START and refuses to load vmcore
Summary: crash fails to find MAGIC_START and refuses to load vmcore
Status: IN_PROGRESS
Alias: None
Product: PUBLIC SUSE Linux Enterprise Server 15 SP3
Classification: SUSE Linux Enterprise Server
Component: Other (show other bugs)
Version: SLES15SP3Maint-Upd
Hardware: x86-64 SLES 12
: P5 - None : Normal
Target Milestone: unspecified
Assignee: David Mair
QA Contact: E-mail List
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2024-04-27 06:59 UTC by Ganapathi CH
Modified: 2024-05-08 17:37 UTC (History)
2 users (show)

See Also:
Found By: Third Party Developer/Partner
Services Priority:
Business Priority:
Blocker: ---
Marketing QA Status: ---
IT Deployment: ---


Attachments
vmcore from SLES-12-SP5 that cannot be opened using crash (16.26 MB, application/x-zip-compressed)
2024-04-27 06:59 UTC, Ganapathi CH
Details

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Description Ganapathi CH 2024-04-27 06:59:03 UTC
Created attachment 874526 [details]
vmcore from SLES-12-SP5 that cannot be opened using crash

I have tried opening the vmcore on both SLES-15-SP4 and SLES-12-SP5 without success.

# crash vmcore -f vmlinux-4.12.14-122.144-default.gz vmlinux-4.12.14-122.144-default.debug

crash 7.2.1
Copyright (C) 2002-2017  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"...

WARNING: kernel relocated [128MB]: patching 83518 gdb minimal_symbol values

WARNING: could not find MAGIC_START!
WARNING: cannot read linux_banner string
crash: vmlinux-4.12.14-122.144-default.debug and vmcore do not match!

Usage:

  crash [OPTION]... NAMELIST MEMORY-IMAGE[@ADDRESS]     (dumpfile form)
  crash [OPTION]... [NAMELIST]                          (live system form)

Enter "crash -h" for details.

Crash tried with -d 10:

# crash vmcore -d 10 -f vmlinux-4.12.14-122.144-default.gz vmlinux-4.12.14-122.144-default.debug



crash 7.2.1
Copyright (C) 2002-2017  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.

compressed kdump: header->utsname.machine: x86_64
compressed kdump: memory bitmap offset: 4000
diskdump_data:
          filename: vmcore
             flags: 6 (KDUMP_CMPRS_LOCAL|ERROR_EXCLUDED)
               dfd: 3
               ofp: 0
      machine_type: 62 (EM_X86_64)

            header: 171bbf0
           signature: "KDUMP   "
      header_version: 6
             utsname:
               sysname: Linux
              nodename: geroescl1n3
               release: 4.12.14-122.144-default
               version: #1 SMP Mon Dec 12 09:21:50 UTC 2022 (bccc371)
               machine: x86_64
            domainname: (none)
           timestamp:
                tv_sec: 640acf09
               tv_usec: 0
              status: 2 (DUMP_DH_COMPRESSED_LZO)
          block_size: 4096
        sub_hdr_size: 3
       bitmap_blocks: 2080
           max_mapnr: 34078720
    total_ram_blocks: 0
       device_blocks: 0
      written_blocks: 0
         current_cpu: 0
             nr_cpus: 24
      tasks[nr_cpus]: 0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0
                      0

        sub_header: 0 (n/a)

  sub_header_kdump: 171cc00
           phys_base: de2000000
          dump_level: 31 (0x1f) (DUMP_EXCLUDE_ZERO|DUMP_EXCLUDE_CACHE|DUMP_EXCLUDE_CACHE_PRI|DUMP_EXCLUDE_USER_DATA|DUMP_EXCLUDE_FREE)
               split: 0
           start_pfn: (unused)
             end_pfn: (unused)
   offset_vmcoreinfo: 12768 (0x31e0)
     size_vmcoreinfo: 1994 (0x7ca)
                      OSRELEASE=4.12.14-122.144-default
                      NUMBER(SUSE_PRODUCT_CODE)=17564928
                      PAGESIZE=4096
                      SYMBOL(init_uts_ns)=ffffffff8a0132a0
                      SYMBOL(node_online_map)=ffffffff8a22a700
                      SYMBOL(swapper_pg_dir)=ffffffff8a00a000
                      SYMBOL(_stext)=ffffffff89000000
                      SYMBOL(vmap_area_list)=ffffffff8a11c250
                      SYMBOL(mem_section)=ffffffff8a9c3980
                      LENGTH(mem_section)=4096
                      SIZE(mem_section)=32
                      OFFSET(mem_section.section_mem_map)=0
                      SIZE(page)=64
                      SIZE(pglist_data)=171968
                      SIZE(zone)=1472
                      SIZE(free_area)=88
                      SIZE(list_head)=16
                      SIZE(nodemask_t)=128
                      OFFSET(page.flags)=0
                      OFFSET(page._refcount)=28
                      OFFSET(page.mapping)=8
                      OFFSET(page.lru)=32
                      OFFSET(page._mapcount)=24
                      OFFSET(page.private)=48
                      OFFSET(page.compound_dtor)=40
                      OFFSET(page.compound_order)=44
                      OFFSET(page.compound_head)=32
                      OFFSET(pglist_data.node_zones)=0
                      OFFSET(pglist_data.nr_zones)=171232
                      OFFSET(pglist_data.node_start_pfn)=171240
                      OFFSET(pglist_data.node_spanned_pages)=171256
                      OFFSET(pglist_data.node_id)=171264
                      OFFSET(zone.free_area)=192
                      OFFSET(zone.vm_stat)=1280
                      OFFSET(zone.spanned_pages)=120
                      OFFSET(free_area.free_list)=0
                      OFFSET(list_head.next)=0
                      OFFSET(list_head.prev)=8
                      OFFSET(vmap_area.va_start)=0
                      OFFSET(vmap_area.list)=48
                      LENGTH(zone.free_area)=11
                      SYMBOL(log_buf)=ffffffff8a068d08
                      SYMBOL(log_buf_len)=ffffffff8a068d00
                      SYMBOL(log_first_idx)=ffffffff8a898220
                      SYMBOL(clear_idx)=ffffffff8a8981f4
                      SYMBOL(log_next_idx)=ffffffff8a898210
                      SIZE(printk_log)=16
                      OFFSET(printk_log.ts_nsec)=0
                      OFFSET(printk_log.len)=8
                      OFFSET(printk_log.text_len)=10
                      OFFSET(printk_log.dict_len)=12
                      LENGTH(free_area.free_list)=5
                      NUMBER(NR_FREE_PAGES)=0
                      NUMBER(PG_lru)=5
                      NUMBER(PG_private)=12
                      NUMBER(PG_swapcache)=9
                      NUMBER(PG_swapbacked)=18
                      NUMBER(PG_slab)=8
                      NUMBER(PG_hwpoison)=22
                      NUMBER(PG_head_mask)=32768
                      NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE)=-128
                      NUMBER(HUGETLB_PAGE_DTOR)=2
                      NUMBER(phys_base)=59626225664
                      SYMBOL(init_top_pgt)=ffffffff8a00a000
                      SYMBOL(node_data)=ffffffff8a226280
                      LENGTH(node_data)=1024
                      KERNELOFFSET=8000000
                      NUMBER(KERNEL_IMAGE_SIZE)=1073741824
                      NUMBER(sme_mask)=0
                      CRASHTIME=1678429961
         offset_note: 4200 (0x1068)
           size_note: 10564 (0x2944)
           notes_buf: 171dc10
  num_prstatus_notes: 24
            notes[0]: 171dc10 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 0000000000000000
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 0000000000000ef0
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 0000000000000000  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffffff8a003e20
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[1]: 171dd74 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 0000000000000001
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000014  R10: 0000000000000f10
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 0000000000000001  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba52801d7e88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[2]: 171ded8 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 0000000000000002
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 0000000000000415
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 0000000000000002  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba52801dfe88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[3]: 171e03c (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 0000000000000003
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 0000000000003f4c
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 0000000000000003  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba52801e7e88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[4]: 171e1a0 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 0000000000000004
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 0000000000001ea2
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 0000000000000004  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba52801efe88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[5]: 171e304 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 0000000000000005
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000014  R10: 0000000000001cb4
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 0000000000000005  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba52801f7e88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[6]: 171e468 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 0000000000000006
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 000000000000011b
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 0000000000000006  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba528644be88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[7]: 171e5cc (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 18653  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: 000000000000038d  R14: 0000000000000000
                           R13: 000000000001eb98  R12: ffffffffc0876ce0
                           RBP: ffff939f02d6b8a8  RBX: ffff939f02d6b788
                           R11: ffff939b3a196300  R10: ffffba532be87bf0
                            R9: ffffba532be87d58   R8: 0000000000000000
                           RAX: 0000000000540101  RCX: 0000000000200000
                           RDX: ffff93ba73ce3e80  RSI: 0000000000000000
                           RDI: ffffffffc0bf3cc0  RIP: ffffffff890e6298
                        RFLAGS: 0000000000000202  RSP: ffffba532be87bf8
                       FS_BASE: 00007f3da06ab700
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[8]: 171e730 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 4916  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffff93aa3a26b5b8  R14: ffffba528d0efaa8
                           R13: ffff93a9fc678140  R12: 0000000000000000
                           RBP: ffffba528bf0fed0  RBX: ffffba528d6177b0
                           R11: 0000000000000018  R10: 0000000000000286
                            R9: 0000000000000000   R8: 0000000000000000
                           RAX: 0000000000540101  RCX: 0000000000000101
                           RDX: 0000000000000001  RSI: 0000000000000000
                           RDI: ffffffffc0bf3cc0  RIP: ffffffff890e62fd
                        RFLAGS: 0000000000000202  RSP: ffffba528bf0feb0
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[9]: 171e894 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 18649  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: 00000000000001f2  R14: 0000000000000000
                           R13: 000000000001f237  R12: ffffffffc0876ce0
                           RBP: ffff939fefe4b1a8  RBX: ffff939fefe4b088
                           R11: ffffffffffffff9c  R10: ffffba532be7fbf0
                            R9: ffffba532be7fd58   R8: 0000000000000000
                           RAX: 0000000000000000  RCX: 0000000000280000
                           RDX: ffff93ba73d23e80  RSI: ffff93aa3fba3e80
                           RDI: ffffffffc0bf3cc0  RIP: ffffffff890e6285
                        RFLAGS: 0000000000000246  RSP: ffffba532be7fbf8
                       FS_BASE: 00007f704c8d5700
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[10]: 171e9f8 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 000000000000000a
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 0000000000000209
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 000000000000000a  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba528646be88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[11]: 171eb5c (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 000000000000000b
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 00000000000044af
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 000000000000000b  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba5286473e88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[12]: 171ecc0 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 18646  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: 0000000000000397  R14: 0000000000000000
                           R13: 000000000001eab6  R12: ffffffffc0876ce0
                           RBP: ffff939b8df39168  RBX: ffff939b8df39048
                           R11: ffffffffffffff9c  R10: ffffffffffffffb7
                            R9: ffffba532bb2fd58   R8: 0000000000000000
                           RAX: 0000000000000000  RCX: 0000000000340000
                           RDX: ffff93aa3fba3e80  RSI: ffff93ba73ce3e80
                           RDI: ffffffffc0bf3cc0  RIP: ffffffff890e6280
                        RFLAGS: 0000000000000246  RSP: ffffba532bb2fbf8
                       FS_BASE: 00007fee9bb5b700
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[13]: 171ee24 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 000000000000000d
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 00000000000052a1
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 000000000000000d  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba5286483e88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[14]: 171ef88 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 4845  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffff93aa2f31c080  R14: ffff93aa2f31c080
                           R13: ffff93aa2f31c080  R12: 0000000000000018
                           RBP: 000000000001871e  RBX: ffff93a39281ed10
                           R11: 0000000000aaaaaa  R10: 00000000000003ff
                            R9: 0000000000051d42   R8: 0000000000000000
                           RAX: 0000000000000063  RCX: 0000000000000000
                           RDX: 0000000000000001  RSI: ffff93aa3fbd7948
                           RDI: ffff93aa3fbd7948  RIP: ffffffffc07da651
                        RFLAGS: 0000000000010296  RSP: ffffba528cad7e80
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[15]: 171f0ec (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 000000000000000f
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 0000000000004e34
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 000000000000000f  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba5286493e88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[16]: 171f250 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 0000000000000010
                           R13: 0000000000000002  R12: 0000000000000010
                           RBP: 0000000000000003  RBX: 0000000000000004
                           R11: 0000000000000018  R10: 0000000000000ef7
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000010  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 0000000000000010  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba528649be88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[17]: 171f3b4 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 0000000000000011
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 0000000000004008
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 0000000000000011  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba52864a3e88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[18]: 171f518 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 0000000000000012
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 0000000000000479
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 0000000000000012  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba52864abe88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[19]: 171f67c (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 0000000000000013
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 0000000000003094
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 0000000000000013  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba52864b3e88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[20]: 171f7e0 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 18650  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: 0000000000000393  R14: 0000000000000000
                           R13: 000000000001f237  R12: ffffffffc0876ce0
                           RBP: ffff939f7517aba8  RBX: ffff939f7517aa88
                           R11: ffffffffffffff9c  R10: ffffffffffffffbb
                            R9: ffffba532a693d58   R8: 0000000000000000
                           RAX: 0000000000000000  RCX: 0000000000540000
                           RDX: ffff93aa3fca3e80  RSI: ffff93ba73d23e80
                           RDI: ffffffffc0bf3cc0  RIP: ffffffff890e6285
                        RFLAGS: 0000000000000246  RSP: ffffba532a693bf8
                       FS_BASE: 00007fd6dde71700
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[21]: 171f944 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 0000000000000015
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 00000000000003fe
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 0000000000000015  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba52864c3e88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[22]: 171faa8 (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 0000000000000016
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 0000000000000f00
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 0000000000000016  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba52864cbe88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
            notes[23]: 171fc0c (NT_PRSTATUS)
                      si.signo: 0  si.code: 0  si.errno: 0
                      cursig: 0  sigpend: 0  sighold: 0
                      pid: 0  ppid: 0  pgrp: 0  sid:0
                      utime: 0.000000  stime: 0.000000
                      cutime: 0.000000  cstime: 0.000000
                      ORIG_RAX: ffffffffffffffff  fpvalid: 0
                           R15: ffffffff8a1714c0  R14: 0000000000000017
                           R13: 0000000000000003  R12: 0000000000000020
                           RBP: 0000000000000004  RBX: 0000000000000008
                           R11: 0000000000000018  R10: 0000000000006555
                            R9: ffffffe91cc49f1d   R8: 0000000000000004
                           RAX: 0000000000000020  RCX: 0000000000000001
                           RDX: 0000000000000000  RSI: ffffffff8a1714c0
                           RDI: 0000000000000017  RIP: ffffffff89754355
                        RFLAGS: 0000000000000046  RSP: ffffba52864d3e88
                       FS_BASE: 0000000000000000
                       GS_BASE: 0000000000000000
                            CS: 0010  SS: 0018  DS: 0000
                            ES: 0000  FS: 0000  GS: 0000
       snapshot_task: 0
      num_qemu_notes: 0
        NOTE offsets: 1068 (NT_PRSTATUS)
                      11cc (NT_PRSTATUS)
                      1330 (NT_PRSTATUS)
                      1494 (NT_PRSTATUS)
                      15f8 (NT_PRSTATUS)
                      175c (NT_PRSTATUS)
                      18c0 (NT_PRSTATUS)
                      1a24 (NT_PRSTATUS)
                      1b88 (NT_PRSTATUS)
                      1cec (NT_PRSTATUS)
                      1e50 (NT_PRSTATUS)
                      1fb4 (NT_PRSTATUS)
                      2118 (NT_PRSTATUS)
                      227c (NT_PRSTATUS)
                      23e0 (NT_PRSTATUS)
                      2544 (NT_PRSTATUS)
                      26a8 (NT_PRSTATUS)
                      280c (NT_PRSTATUS)
                      2970 (NT_PRSTATUS)
                      2ad4 (NT_PRSTATUS)
                      2c38 (NT_PRSTATUS)
                      2d9c (NT_PRSTATUS)
                      2f00 (NT_PRSTATUS)
                      3064 (NT_PRSTATUS)
    offset_eraseinfo: 0 (0x0)
      size_eraseinfo: 0 (0x0)
        start_pfn_64: (unused)
          end_pfn_64: (unused)
        max_mapnr_64: 34078720 (0x2080000)

       data_offset: 824000
        block_size: 4096
       block_shift: 12
            bitmap: 7f933f049010
        bitmap_len: 8519680
         max_mapnr: 34078720 (0x2080000)
   dumpable_bitmap: 7f933e828010
              byte: 0
               bit: 0
   compressed_page: 17609a0
         curbufptr: 0

 page_cache_hdr[0]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 1750990
        pg_hit_count: 0
 page_cache_hdr[1]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 1751990
        pg_hit_count: 0
 page_cache_hdr[2]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 1752990
        pg_hit_count: 0
 page_cache_hdr[3]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 1753990
        pg_hit_count: 0
 page_cache_hdr[4]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 1754990
        pg_hit_count: 0
 page_cache_hdr[5]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 1755990
        pg_hit_count: 0
 page_cache_hdr[6]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 1756990
        pg_hit_count: 0
 page_cache_hdr[7]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 1757990
        pg_hit_count: 0
 page_cache_hdr[8]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 1758990
        pg_hit_count: 0
 page_cache_hdr[9]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 1759990
        pg_hit_count: 0
page_cache_hdr[10]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 175a990
        pg_hit_count: 0
page_cache_hdr[11]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 175b990
        pg_hit_count: 0
page_cache_hdr[12]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 175c990
        pg_hit_count: 0
page_cache_hdr[13]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 175d990
        pg_hit_count: 0
page_cache_hdr[14]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 175e990
        pg_hit_count: 0
page_cache_hdr[15]:
            pg_flags: 0 ()
             pg_addr: 0
           pg_bufptr: 175f990
        pg_hit_count: 0

    page_cache_buf: 1750990
       evict_index: 0
         evictions: 0
          accesses: 0
      cached_reads: 0
       valid_pages: 1740580
readmem: read_diskdump()
GETBUF(44 -> 0)
NOTE: gnu_debuglink file: vmlinux-4.12.14-122.144-default.debug
crc32: 5f2353bd
  GETBUF(35 -> 1)
vmlinux-4.12.14-122.144-default.debug: CRC matches
  FREEBUF(1)
FREEBUF(0)
KASLR:
  _stext from vmlinux-4.12.14-122.144-default.gz_f9ql5h: ffffffff81000000
  _stext from vmcoreinfo: ffffffff89000000
  relocate: 8000000 (128MB)
crash: pv_init_ops exists: ARCH_PVOPS
VMCOREINFO: NUMBER(phys_base): 59626225664 -> de2000000
gdb vmlinux-4.12.14-122.144-default.debug
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"...
GETBUF(288 -> 0)
  GETBUF(1500 -> 1)

WARNING: kernel relocated [128MB]: patching 83518 gdb minimal_symbol values

  FREEBUF(1)
FREEBUF(0)
<readmem: ffffffff8a04ede8, KVADDR, "page_offset_base", 8, (FOE), d45a28>
<read_diskdump: addr: ffffffff8a04ede8 paddr: dec04ede8 cnt: 8>
read_diskdump: paddr/pfn: dec04ede8/dec04e -> cache physical page: dec04e000
<readmem: ffffffff89c2a2e0, KVADDR, "kernel_config_data", 32768, (ROE), 2f297b0>
<read_diskdump: addr: ffffffff89c2a2e0 paddr: debc2a2e0 cnt: 3360>
read_diskdump: paddr/pfn: debc2a2e0/debc2a -> cache physical page: debc2a000
<read_diskdump: addr: ffffffff89c2b000 paddr: debc2b000 cnt: 4096>
read_diskdump: paddr/pfn: debc2b000/debc2b -> cache physical page: debc2b000
<read_diskdump: addr: ffffffff89c2c000 paddr: debc2c000 cnt: 4096>
read_diskdump: paddr/pfn: debc2c000/debc2c -> cache physical page: debc2c000
<read_diskdump: addr: ffffffff89c2d000 paddr: debc2d000 cnt: 4096>
read_diskdump: paddr/pfn: debc2d000/debc2d -> cache physical page: debc2d000
<read_diskdump: addr: ffffffff89c2e000 paddr: debc2e000 cnt: 4096>
read_diskdump: paddr/pfn: debc2e000/debc2e -> cache physical page: debc2e000
<read_diskdump: addr: ffffffff89c2f000 paddr: debc2f000 cnt: 4096>
read_diskdump: paddr/pfn: debc2f000/debc2f -> cache physical page: debc2f000
<read_diskdump: addr: ffffffff89c30000 paddr: debc30000 cnt: 4096>
read_diskdump: paddr/pfn: debc30000/debc30 -> cache physical page: debc30000
<read_diskdump: addr: ffffffff89c31000 paddr: debc31000 cnt: 4096>
read_diskdump: paddr/pfn: debc31000/debc31 -> cache physical page: debc31000
<read_diskdump: addr: ffffffff89c32000 paddr: debc32000 cnt: 736>
read_diskdump: paddr/pfn: debc32000/debc32 -> cache physical page: debc32000
WARNING: could not find MAGIC_START!
GETBUF(288 -> 0)
FREEBUF(0)
GETBUF(1024 -> 0)
<readmem: ffffffff8a228ec0, KVADDR, "possible", 1024, (ROE), f86fa0>
<read_diskdump: addr: ffffffff8a228ec0 paddr: dec228ec0 cnt: 320>
read_diskdump: paddr/pfn: dec228ec0/dec228 -> cache physical page: dec228000
<read_diskdump: addr: ffffffff8a229000 paddr: dec229000 cnt: 704>
read_diskdump: paddr/pfn: dec229000/dec229 -> cache physical page: dec229000
cpu_possible_mask: cpus: (none)
<readmem: ffffffff8a2286c0, KVADDR, "present", 1024, (ROE), f86fa0>
<read_diskdump: addr: ffffffff8a2286c0 paddr: dec2286c0 cnt: 1024>
read_diskdump: paddr/pfn: dec2286c0/dec228 -> physical page is cached: dec228000
 cpu_present_mask: cpus: (none)
<readmem: ffffffff8a228ac0, KVADDR, "online", 1024, (ROE), f86fa0>
<read_diskdump: addr: ffffffff8a228ac0 paddr: dec228ac0 cnt: 1024>
read_diskdump: paddr/pfn: dec228ac0/dec228 -> physical page is cached: dec228000
  cpu_online_mask: cpus: (none)
<readmem: ffffffff8a2282c0, KVADDR, "active", 1024, (ROE), f86fa0>
<read_diskdump: addr: ffffffff8a2282c0 paddr: dec2282c0 cnt: 1024>
read_diskdump: paddr/pfn: dec2282c0/dec228 -> physical page is cached: dec228000
  cpu_active_mask: cpus: (none)
FREEBUF(0)
<readmem: ffffffff8a03dbc0, KVADDR, "pv_init_ops", 8, (ROE), 7ffcee0bed08>
<read_diskdump: addr: ffffffff8a03dbc0 paddr: dec03dbc0 cnt: 8>
read_diskdump: paddr/pfn: dec03dbc0/dec03d -> cache physical page: dec03d000
GETBUF(288 -> 0)
FREEBUF(0)
GETBUF(288 -> 0)
FREEBUF(0)
<readmem: ffffffff8a8b1360, KVADDR, "shadow_timekeeper xtime_sec", 8, (ROE), 7ffcee0becb8>
<read_diskdump: addr: ffffffff8a8b1360 paddr: dec8b1360 cnt: 8>
read_diskdump: paddr/pfn: dec8b1360/dec8b1 -> cache physical page: dec8b1000
xtime timespec.tv_sec: 0: Thu Jan  1 05:30:00 1970
<readmem: ffffffff8a0132a4, KVADDR, "init_uts_ns", 390, (ROE), d2bc7c>
<read_diskdump: addr: ffffffff8a0132a4 paddr: dec0132a4 cnt: 390>
read_diskdump: paddr/pfn: dec0132a4/dec013 -> cache physical page: dec013000
utsname:
     sysname:
    nodename:
     release:
     version:
     machine:
  domainname:
base kernel version: 0.12.14
<readmem: ffffffff89c000c0, KVADDR, "accessible check", 8, (ROE|Q), 7ffcee0bc018>
<read_diskdump: addr: ffffffff89c000c0 paddr: debc000c0 cnt: 8>
read_diskdump: paddr/pfn: debc000c0/debc00 -> cache physical page: debc00000
<readmem: ffffffff89c000c0, KVADDR, "read_string characters", 1499, (ROE|Q), 7ffcee0bc370>
<read_diskdump: addr: ffffffff89c000c0 paddr: debc000c0 cnt: 1499>
read_diskdump: paddr/pfn: debc000c0/debc00 -> physical page is cached: debc00000
WARNING: cannot read linux_banner string
linux_banner:

crash: vmlinux-4.12.14-122.144-default.debug and vmcore do not match!

Usage:

  crash [OPTION]... NAMELIST MEMORY-IMAGE[@ADDRESS]     (dumpfile form)
  crash [OPTION]... [NAMELIST]                          (live system form)

Enter "crash -h" for details.
Comment 1 Ganapathi CH 2024-04-27 07:04:03 UTC
The kernel vmcore is from SLES-12-SP5. However, the SUSE bug filing does not allow to select SLES-12-SP5 as the product.

How can this vmcore be opened using crash?

I tried with SLES-12-SP5 with kernel-default-4.12.14-122.144.1.x86_64.rpm. But no success.

Please help me to open the vmcore using crash.
Comment 2 David Mair 2024-04-29 16:39:53 UTC
(In reply to Ganapathi CH from comment #1)
> The kernel vmcore is from SLES-12-SP5. However, the SUSE bug filing does not
> allow to select SLES-12-SP5 as the product.
> 
> How can this vmcore be opened using crash?
> 
> I tried with SLES-12-SP5 with kernel-default-4.12.14-122.144.1.x86_64.rpm.
> But no success.
> 
> Please help me to open the vmcore using crash.

The best first choice solution to this is to use a later version of SLES (or openSUSE) as the place you perform the use of crash, e.g. SLES15-SP5 (or the most recent openSUSE version). The process of performing debug of a coredump using a given release of crash on a SUSE product is supported for debug of coredumps from previous versions of SUSE products and the latest crash release on _any_ product is crash 8.0.4, which is substantially more useful and with broader kernel support than the very old crash 7.2.1

However, while that might give you immediate functionality, the same statement combined with your report implies that the kernel on SLES12-SP5 has been updated such that a crash update is required on SLES12-SP5 for normal kernel debugging. My preferred approach would be generalizing the use of crash 8 versions on supported products when this type of thing happens and, internally, the way crash is managed as source code for build was recently separated from source code management for general packages in individual products. However, whether crash 8 can be released for SLES12-SP5 requires verification before consideration and cannot result in a quick solution for you, whereas the approach suggested above can.
Comment 3 Ganapathi CH 2024-04-30 03:45:41 UTC
The same result with crash 8.0.4. Looks like the crash is unable to find the string 'linux_banner' in vmcore. But why?

# crash -d vmcore -f vmlinux-4.12.14-122.144-default.gz usr/lib/debug/boot/vmlinux-4.12.14-122.144-default.debug

crash 8.0.4
Copyright (C) 2002-2022  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, 2020-2022  NEC Corporation
Copyright (C) 1999, 2002, 2007  Silicon Graphics, Inc.
Copyright (C) 1999, 2000, 2001, 2002  Mission Critical Linux, Inc.
Copyright (C) 2015, 2021  VMware, 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) 10.2
Copyright (C) 2021 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-pc-linux-gnu".
Type "show configuration" for configuration details.
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"...

WARNING: could not find MAGIC_START!
crash: usr/lib/debug/boot/vmlinux-4.12.14-122.144-default.debug and /proc/kcore do not match!

Usage:

  crash [OPTION]... NAMELIST MEMORY-IMAGE[@ADDRESS]     (dumpfile form)
  crash [OPTION]... [NAMELIST]                          (live system form)

Enter "crash -h" for details.
Comment 4 David Mair 2024-04-30 05:29:14 UTC
Thank you for testing and the feedback. I've previously worked bug where crash was not possible to find the banner. It was a long time ago but, as I recall it was a bit strange. I'll start researching it in my Tuesday (2024-04-30) morning.
Comment 5 David Mair 2024-04-30 23:51:35 UTC
A way to get crash to start under failure circumstances is to use the --minimal argument on the crash command-line. A large amount of the startup verification is not performed, but the result is a very limited set of functionality in crash. Going back to crash on SLES12-SP5, you should be able to start it in --minimal mode then use something like:

crash> set debug 8
crash> rd linux_banner 20
crash> rd -a linux_banner

It should demonstrate the path through memory (and the coredump) at debug 8 level. If linux_banner is discoverable the command's should dump the memory containing it and it should identify the kernel and version number, e.g. Linux version 4.12.14-122.144.

The failure case I was referring to in comment #4 was that the "type" of the symbol linux_banner caused the banner string itself to be referenced as a pointer and since it's text, treating it as an address means it would be unlikely to represent any address in system memory. The address of linux banner would appear to be something like: 0x4C6C6E7578205665 (or 0x65562078756E6C4C), The first 8 bytes of linux_banner ASCII text treated as pointer to actual linux_banner content. That doesn't appear to be the case from your debug launch of crash but it's worth noting, output from the following might help in minimal mode:

crash> info linux_banner

You could always expand the compressed kernel to limit working through it's content to direct access rather than de-compress and access.

If crash will not start when using --minimal on the command-line then it is likely the coredump (vmcore) is damaged or faulty in some way. That can happen if it is obtained using a method other than kdump, e.g. a xen memory image or vmware's equivalent. There have been some compatibility issues between such memory images and a kdump memory image.

If it is a kdump memory image then if storage space permits then it couldn't hurt to use the dump level that includes the most memory in the vmcore image, e.g. dump level of zero (no pages filtered). You can set that in YAST or directly in /etc/sysconfig/kdump with the option KDUMP_DUMPLEVEL="<value>". Even on a system with a huge amount of memory it is a reasonable elimination case for inability to find objects by using KDUMP_DUMPLEVEL="0"

As a last resort with the kdump model ensuring dump file format by using KDUMP_DUMPFORMAT="ELF" in /etc/sysconfig/kdump is a worthwhile elimination combined with the use of KDUMP_DUMPLEVEL="0"

Beyond that, for debugging it I'd need access to a coredump exhibiting the problem (it would save time to have it and the matching kernel/debuginfo files as well) but let's take that up after your experience with all in the previous paragraphs in this post.
Comment 6 Ganapathi CH 2024-05-02 06:19:31 UTC
crash --minimal can open vmcore. However, with very minimal commands supported it is not useful for diagnosing the problem. Here is the output of linux_banner from crash --minimal:

crash> rd -a linux_banner
<addr: ffffffff89c000c0 count: 9223372036854775807 flag: 2080 (KVADDR)>
<readmem: ffffffff89c000c0, KVADDR, "ascii", 1, (FOE), 7ffc758f2910>
<read_diskdump: addr: ffffffff89c000c0 paddr: debc000c0 cnt: 1>
read_diskdump: paddr/pfn: debc000c0/debc00 -> physical page is cached: debc00000

So, the vmcore seems to be good or else the 'minimal' also wouldn't have worked, I guess.

But the limited scope of commands is hindering any further progress.
Comment 7 Ganapathi CH 2024-05-02 06:28:00 UTC
I have also attached crash folder from /var/crash/ so you can check the actual vmcore. I have not attached the vmlinux-4...debug file as it is too big (even after compressing with tar jcf).
Comment 8 David Mair 2024-05-02 07:02:16 UTC
I know --minimal mode has very limited functionality, I said it in comment #5. I was asking you to try it only to get the diagnostic information when reading linux_banner. Thank you, Plainly linux_banner is accessible as an identity, though that doesn't of itself demonstrate the coredump has no faults. In fact, I'm not sure I agree the rd -a command worked, I don't see the ASCII dump of memory from the address in linux_banner in comment #6. The command should have ended by outputting something like this:


crash> rd -a linux_banner
    ...the details about what's being parsed due to the debug level, then...
    c082a020:  Linux version 4.8.23-144.232.x86_64 (suseckbuild@hs20-bc2-4.buil
    c082a05c:  dab.suse.com) (gcc version 4.4.4 20100726 (SUSE LLC 4.8.2-09)
    c082a098:   (GCC) ) #1 SMP Tue May 9 20:25:37 CET 2021

That is a mock-up and obviously the address dumped would not be c082a020 in your case, the kernel version, builder and compiler version would be different as well. But, it would be very similar and your output appears to have showed nothing of the content of linux_banner. The identifier linux_banner is known, and it's address, but reading from the location referenced apears to have shown no output.

I see the material you attached when you created the bug. I'll investigate using crash in gdb and aim to diagnose it then report back. It may take me two or three days, Debugging crash as it debugs the kernel requires careful consideraion of whether what is being observed is runtime activity in crash and/or interpretation of the core dump as a runtime image of the kernel.
Comment 9 David Mair 2024-05-06 23:29:35 UTC
Here's the end of the debug output I get with crash 8.0.4 on openSUSE Tumbleweed using your attached files, de-compressing the kernel binary and using the rpm version of vmlinux-4.12.14-122.144-default.debug that I excepted to match the dumped vmlinux-4.12.14-122.144-default:

<readmem: ffffffff8a04ede8, KVADDR, "page_offset_base", 8, (FOE|Q), 55ad639e24c8>
<read_diskdump: addr: ffffffff8a04ede8 paddr: dec04ede8 cnt: 8>
read_diskdump: paddr/pfn: dec04ede8/dec04e -> cache physical page: dec04e000
read_diskdump/cache_page: descriptor with zero offset found at paddr/pfn/pos: dec04e000/dec04e/4262ba
read_diskdump: READ_ERROR: cannot cache page: dec04e000
crash: page incomplete: kernel virtual address: ffffffff8a04ede8  type: "page_offset_base"

Crucially, the value of page_offset_base (as I understand it) would be required to read kernel text, including the content of a symbol like linux_banner. From the point of view of diagnosis only:

* The readmem fails
* The attempt to read the value is from kernel virtual address ffffffff8a04ede8
* 8 bytes from physical address dec04ede8
* dec04ede8 is read into a cached physical page located at dec04e000
* caching the page fails de to a zero offset found at the physical address
* Therefore, page_offset_base cannot be read from the cached page

I can't even start crash in --minimal mode using this coredump. This does NOT match the behavior you observe, e.g. your debug output for page_offset_base is:

<readmem: ffffffff8a04ede8, KVADDR, "page_offset_base", 8, (FOE), d45a28>
<read_diskdump: addr: ffffffff8a04ede8 paddr: dec04ede8 cnt: 8>
read_diskdump: paddr/pfn: dec04ede8/dec04e -> cache physical page: dec04e000

* The kernel virtual address is the same
* The physical address is the same
* The read to cache succeeds and subsequent steps of the initialization take place for your use

On the basis of this I'm not convinced the attached coredump is complete. It would help to have a checksum of it (e.g. sha256 or sha512) so that I can confirm I am working on the same file as you.

Nevertheless, the behavior I see is not entirely different from yours, I see it unable to read a basic memory reference point, you see it unable to read a slightly less significant basic memory reference point but both cases are failures to read a symbol's value.

The fact that you were able to start crash in --minimal mode proves nothing about the integrity of the coredump, --minimal excludes a lot of normal initialization tests and tries to permit basic access to the coredump as a memory image. IOW, if the initialization required for crash to debug the coredump as a runtime image is not performed but crash loads (--minimal) it only proves that addressing some objects works in the coredump, not that the coredump has enough integrity for utility with crash.

I strongly recommend retrying with a coredump created using KDUMP_DUMPLEVEL="0". It's not suggested as a solution, but rather a way to exclude some potential problem cases that might cause the observed symptoms.

Given that I can't reproduce the problem you see but I see a similar problem (failure to read a more significant reference than your observation) I have little to go on other than the appearance that the coredump does not have the required integrity for normal use with crash. That might have happened when it was created, possibly due to the way it was filtered when created, or possibly in the manner it was made available to you. For any of these cases I would always want to start with a coredump created at kdump level zero then work down from that. I would also like to know what happens on a coredump triggered deliberately on an equivalent SLES12-SP5 system that is operating normally.
Comment 10 Ganapathi CH 2024-05-07 17:45:23 UTC
crash --minimal mode didn't open for me too on openSUSE Tumbleweed. However, it can be opened in --minimal mode on a SLES12-SP5 server.
Comment 11 David Mair 2024-05-07 18:01:40 UTC
(In reply to Ganapathi CH from comment #10)
> crash --minimal mode didn't open for me too on openSUSE Tumbleweed. However,
> it can be opened in --minimal mode on a SLES12-SP5 server.

Thanks for the verification. It is still as I said, --minimal demonstrates little about the integrity of the coredump while allowing limited access to it's content. The evidence still suggests to me that the coredump could be bad. For progress as a crash bug it has to be verified that the problem exists in a coredump taken from a system that is not in the process of failing/aborting/oopsing/etc, i.e. a triggered coredump from idle server running normally, and the starting point has to be that said coredump has no content filtered (kdump level zero). If that coredump can be opened then it is likely the experience you are having with the attached coredump is not a crash bug and alterative configuration of kdump might help in the real problem case.
Comment 12 David Mair 2024-05-07 19:48:15 UTC
I'm working on a test VM to try to experiment with kdump/crash. I recommend you perform your own test case as described in comment #11 but I'll post my results if they are needed.
Comment 13 David Mair 2024-05-07 20:20:45 UTC
I also need to make note that the current kernel version for SLES12-SP5 is 4.12.14-122.201.1 and that the problem is reported for kernel 4.12.14-122.144 which is from December 2022 as I understand it and substantially outdated.
Comment 14 David Mair 2024-05-07 20:34:10 UTC
(In reply to David Mair from comment #12)
> I'm working on a test VM to try to experiment with kdump/crash. I recommend
> you perform your own test case as described in comment #11 but I'll post my
> results if they are needed.

OK. FOR THE RECORD:

I cannot reproduce the reported problem using crash 7.2.1 on SLES12-SP5 patched to-date, using a triggered kdump coredump from an idle but operational SLES12-SP5 server with the current maintenance kernel version of 4.12.14-122.201. Crash loads the coredump just fine and reaches the crash > console prompt without error. The kdump level used was the install default of 23, which I understand excludes only the following:

Pages Filled with Zeros
Cache Pages
Cache Private Pages
Free Pages

The dump format was LZO Compressed which makes the only difference between the format of my coredump and the supplied one is that I included User Data Pages. Which, as I mentioned, is the default filtering.

My kdump on a 6GB host was configured with the following startup configuration:

Low Memory: 72MiB
High Memory: 165MiB

The coredump triggered from the idle, and not failing server with 6GiB of memory has a compressed size of 111MiB using the above detailed enabled filters and compression.
Comment 15 David Mair 2024-05-07 20:59:08 UTC
I repeated the test with all page type filters enabled (which is KDUMP_DUMP_LEVEL of 31). It's still a patched to-date system, but now using the same KDUMP_DUMP_LEVEL as the reported problem coredump. I still had no problem opening the newly created coredump using crash. The coredump this time was 56MiB.

It's an extremely crude value but, the ratio of physical memory to coredump size I see for a LZO compressed coredump is as-follows by KDUMP_DUMP_LEVEL:

KDUMP_DUMP_LEVEL 23: 55.6 to 1
KDUMP_DUMP_LEVEL 23: 110.5 to 1

If this was a credibly consistent ratio across SLES12-SP5 systems (which is NOT really a fact but is a reasonable assumption  for guidance) then, I would estimate the physical memory is between 24GiB and 32GiB on the system the supplied problem 233MiB coredump was from.

I will now transfer the problem coredump to my test VM to see if there is any difference trying crash with it on a patched to date SLES12-SP5 (though with the problem system's  kernel binary and debuginfo).
Comment 16 David Mair 2024-05-07 21:46:35 UTC
...and using the supplied problem coredump on a patched to-date (May 2024) SLES12-SP5 where the coredump is from a December 2022 kernel (version 4.12.14-122.144) using the matching kernel 4.12.14-122.144 binary and kernel 4.12.14-122.144 debuginfo for the dump of the kernel 4.12.14-122.144 system I observe the reported problem, the value of the linux_banner symbol is output as a 64-bit zero integer:

fffffffff89c00c0: 0000000000000000

This is not valid, the page was read from the coredump and the value at the location in the coredump representing the location of the linux_banner symbol is zero and not either the text of the linux_banner or a pointer address to the linux_banner text.

Going further, using:

crash> rd 0xfffffffff89c00c0 4096

to browse the page supposedly containing linux_banner. Every byte in the page has zero value, i.e. it is a zero page. The kdump dump level was configured to exclude the byte content of zero pages from the coredump, therefore the real content of the page containing linux_banner was either damaged when inserted ito the coredump by kdump or improperly resolved by kdump such that a zero page was that was not the page contianing linux_banner was treated as that page and flagged in the coredump as a zero page. None of these scenarios suggest a problem in crash and further support my opinion that the coredump is invalid and should not be used with crash. Combine these with the fact that I can dump the core on a stable sytem with dump level 23 and level 31 then use it with crash using a patched to date SLES12-SP5.

* I recommend the supplied coredump be considered invalid based on the above analysis
* For progress I strongly recommend patching the problem system to-date and attempt to reproduce the problem underlying the creation of the coredump
* If the underlying problem that caused the core to be dumped is reproduced on a patched to-date SLES12-SP5 and the coredump still cannot be opened by crash then it is likely the underlying cause corrupts memory sufficiently that the a dumped core is of little use
* If that is observed then I strongly recommend that the kdump dump level be set to zero (no filtered pages, all memory in the coredump), the underlying problem be reproduced again and the unfiltered cordump be considered
* If crash still fails to load that unfiltered coredump then I strongly recommend that a coredump be triggered on an idle instance of the system exhibiting the underlying problem (i.e. get a coredump of a working system that the underlying problem can be reproduced on). This should be done as soon as possible after linux boot is complete (i.e. a system that's just up and done almost nothing but boot to idle state)
* If crash does not load that coredump we should continue talking but I would suspect that the coredump of a just booted, idle, patched to-date SLES12-SP5 will not be damaged, matching my observations on a test system and if you can use that coredump with crash then it is improbable that crash has a bug causing the reported problem but something causes the coredump to be invalid when created.
Comment 17 Ganapathi CH 2024-05-08 17:37:30 UTC
Thanks for the analysis and the suggestions. Yes, I agree that is unlikely to be a crash issue; maybe kdump or some other issue.

That coredump was from a customer. I have pinged the customer. Haven't heard back. If the customer responds I will suggest getting the coredump with kdump level 0 and see if I can open that. If not, I will ask for a triggered coredump on the idle server and verify.

You can close this bug for now. If the customer responds and if I get a coredump as suggested but still cannot open I will reach out again. Hope that is fine.