[Crash-utility] crash "bt" and "dmesg" show different messages

[Yuming Cheng]

Hi all,

When using kdump, I find crash "bt" and "dmesg" give different info.
which one is more reliable ?

Thanks,
---cym 


dmesg
/****************************************/
Unable to handle kernel NULL pointer dereference at 0000000000000001 RIP:
 [<0000000000000001>]
PGD 323c6f067 PUD 323f13067 PMD 0
Oops: 0010 [1] SMP
last sysfs file: /devices/pci0000:00/0000:00:00.0/irq
CPU 6
Modules linked in: igb(U) bonding ipv6 xfrm_nalgo crypto_api autofs4 hidp rfcomm l2cap bluetooth lockd sunrpc dm_mirror dm_multipath scsi_dh video hwmon backlight sbs i2c_ec button battery asus_acpi acpi_memhotplug ac parport_pc lp parport sg ixgbe pcspkr i2c_i801 serio_raw i2c_core 8021q dca dm_raid45 dm_message dm_region_hash dm_log dm_mod dm_mem_cache ahci libata shpchp mptsas mptscsih mptbase scsi_transport_sas sd_mod scsi_mod ext3 jbd uhci_hcd ohci_hcd ehci_hcd
Pid: 8894, comm: ifconfig Tainted: G      2.6.18-164.el5debug #1
RIP: 0010:[<0000000000000001>]  [<0000000000000001>]
RSP: 0018:ffff810323dd9cf0  EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffff81032a8e5b68 RCX: 0000000000000000
RDX: 0000000000000006 RSI: 0000000000000001 RDI: ffff81032a8e5b68
RBP: ffff81033aabc850 R08: 0000000000000002 R09: 0000000000000001
R10: ffff81032a8e5c30 R11: ffffffff80049ee3 R12: ffff81032a8e5ba8
R13: 0000000000000006 R14: ffff8103238be000 R15: ffffffff8846ad00
FS:  00002ba7032083f0(0000) GS:ffff810113a9e4c8(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000001 CR3: 00000003242b4000 CR4: 00000000000006e0
Process ifconfig (pid: 8894, threadinfo ffff810323dd8000, task ffff810323f461c0)
Stack:  ffffffff8023de3b ffff81032a8e5b68 ffffffff8023e0d6 ffffffff8023e122
 ffffffff88468eb0 ffff8103238be000 ffffffff8846ad00 ffff8103238be000
 0000000000000000 ffffffff8846ae98 ffffffff8023e12d 0000000000000002
Call Trace:
 [<ffffffff8023de3b>] neigh_cleanup_and_release+0x13/0x2c
 [<ffffffff8023e0d6>] neigh_flush_dev+0x9d/0xc3
 [<ffffffff88439acb>] :ipv6:ndisc_netdev_event+0x30/0x3d
 [<ffffffff8006ae76>] notifier_call_chain+0x20/0x32
 [<ffffffff80238c52>] dev_close+0x6e/0x72
 [<ffffffff80237d24>] dev_change_flags+0x5a/0x119
 [<ffffffff8026cb77>] devinet_ioctl+0x235/0x59c
 [<ffffffff8022f0e3>] sock_ioctl+0x1c7/0x1eb
 [<ffffffff8004465d>] do_ioctl+0x21/0x6b
 [<ffffffff80031f07>] vfs_ioctl+0x45d/0x4bf
 [<ffffffff800c0b9d>] audit_syscall_entry+0x180/0x1b3
 [<ffffffff8004ef9e>] sys_ioctl+0x59/0x78
 [<ffffffff800602a6>] tracesys+0xd5/0xdf

/****************************************/
crash btcrash> bt
PID: 8894   TASK: ffff810323f461c0  CPU: 6   COMMAND: "ifconfig"
 #0 [ffff810323dd9a50] crash_kexec at ffffffff800b6eae
 #1 [ffff810323dd9b10] __die at ffffffff80069087
 #2 [ffff810323dd9b50] do_page_fault at ffffffff8006ad73
 #3 [ffff810323dd9c40] error_exit at ffffffff80060e9d
 #4 [ffff810323dd9c78] skb_dequeue at ffffffff80049ee3
 #5 [ffff810323dd9cf0] neigh_cleanup_and_release at ffffffff8023de3b
 #6 [ffff810323dd9d00] neigh_flush_dev at ffffffff8023e0d6
 #7 [ffff810323dd9d40] neigh_ifdown at ffffffff8023e12d
 #8 [ffff810323dd9d80] ndisc_netdev_event at ffffffff88439acb
 #9 [ffff810323dd9d90] notifier_call_chain at ffffffff8006ae76
#10 [ffff810323dd9db0] dev_close at ffffffff80238c52
#11 [ffff810323dd9dc0] dev_change_flags at ffffffff80237d24
#12 [ffff810323dd9df0] devinet_ioctl at ffffffff8026cb77
#13 [ffff810323dd9e90] sock_ioctl at ffffffff8022f0e3
#14 [ffff810323dd9eb0] do_ioctl at ffffffff8004465d
#15 [ffff810323dd9ed0] vfs_ioctl at ffffffff80031f07
#16 [ffff810323dd9f40] sys_ioctl at ffffffff8004ef9e
#17 [ffff810323dd9f80] tracesys at ffffffff800602a6 (via system_call)
    RIP: 0000003749ccc557  RSP: 00007fff470ea238  RFLAGS: 00000206
    RAX: ffffffffffffffda  RBX: ffffffff800602a6  RCX: ffffffffffffffff
    RDX: 00007fff470ea240  RSI: 0000000000008914  RDI: 0000000000000004
    RBP: 0000000000000000   R8: 00007fff470ea244   R9: 0000000000000002
    R10: 0000000000000001  R11: 0000000000000206  R12: 00007fff470ea360
    R13: 00000000fffffffe  R14: 00007fff470ea530  R15: 0000000000000004
    ORIG_RAX: 0000000000000010  CS: 0033  SS: 002b