Kernel error: DWARF2 unwinder stuck at system_call

SUSE Linux Enterprise Extensions SLES Hardware
1

Hi Everyone,

Following error can be found in /var/log/messages:

Oct 15 05:30:03 sapnode02 kernel: [1333391.788876] ------------[ cut here ]------------
Oct 15 05:30:03 sapnode02 kernel: [1333391.788895] WARNING: at /usr/src/packages/BUILD/kernel-default-3.0.13/linux-3.0/fs/dcache.c:2584 prepend_path+0x189/0x1a0()
Oct 15 05:30:03 sapnode02 kernel: [1333391.788903] Hardware name: ProLiant DL585 G7
Oct 15 05:30:03 sapnode02 kernel: [1333391.788907] Root dentry has weird name <>
Oct 15 05:30:03 sapnode02 kernel: [1333391.788911] Modules linked in: lp parport_pc st ide_cd_mod ide_core ppdev parport ext2 usb_storage af_packet binfmt_misc edd nfs lockd fscache auth_rpcgss nfs_acl sunrpc bonding mperf microcode fuse loop dm_round_robin dm_multipath ipv6_lib netxen_nic hpwdt sg sr_mod hpilo i2c_piix4 pcspkr joydev i2c_core k10temp cdrom container rtc_cmos acpi_power_meter button ext3 jbd mbcache dm_mirror dm_region_hash dm_log linear sd_mod crc_t10dif usbhid hid ohci_hcd uhci_hcd qla2xxx ehci_hcd scsi_transport_fc scsi_tgt usbcore usb_common processor thermal_sys hwmon scsi_dh_emc scsi_dh_hp_sw scsi_dh_alua scsi_dh_rdac scsi_dh dm_snapshot dm_mod ata_generic pata_atiixp ahci libahci libata hpsa cciss scsi_mod [last unloaded: parport_pc]
Oct 15 05:30:03 sapnode02 kernel: [1333391.789039] Supported: Yes
Oct 15 05:30:03 sapnode02 kernel: [1333391.789046] Pid: 38130, comm: checkproc Tainted: G W 3.0.13-0.27-default #1
Oct 15 05:30:03 sapnode02 kernel: [1333391.789051] Call Trace:
Oct 15 05:30:03 sapnode02 kernel: [1333391.789087] [] dump_trace+0x75/0x300
Oct 15 05:30:03 sapnode02 kernel: [1333391.789106] [] dump_stack+0x69/0x6f
Oct 15 05:30:03 sapnode02 kernel: [1333391.789124] [] warn_slowpath_common+0x7b/0xc0
Oct 15 05:30:03 sapnode02 kernel: [1333391.789140] [] warn_slowpath_fmt+0x45/0x50
Oct 15 05:30:03 sapnode02 kernel: [1333391.789156] [] prepend_path+0x189/0x1a0
Oct 15 05:30:03 sapnode02 kernel: [1333391.789172] [] d_path+0xc7/0x100
Oct 15 05:30:03 sapnode02 kernel: [1333391.789187] [] proc_pid_readlink+0xa0/0x100
Oct 15 05:30:03 sapnode02 kernel: [1333391.789206] [] sys_readlinkat+0xbd/0xd0
Oct 15 05:30:03 sapnode02 kernel: [1333391.789222] [] system_call_fastpath+0x16/0x1b
Oct 15 05:30:03 sapnode02 kernel: [1333391.791940] DWARF2 unwinder stuck at system_call_fastpath+0x16/0x1b
Oct 15 05:30:03 sapnode02 kernel: [1333391.791945]
Oct 15 05:30:03 sapnode02 kernel: [1333391.791948] Leftover inexact backtrace:
Oct 15 05:30:03 sapnode02 kernel: [1333391.791951]
Oct 15 05:30:03 sapnode02 kernel: [1333391.791959] —[ end trace 34097b7e21958987 ]—
Oct 15 05:30:03 sapnode02 kernel: klogd 1.4.1, ---------- state change ----------
Oct 15 05:30:04 sapnode02 kernel: [1333391.904945] ------------[ cut here ]------------

Any reason for this kinda message?? The other thing is, this particular server is part of a cluster. The cluster communication get disconnected sometimes (can’t ping to the other server). When the server is reboot, several network restart are carried out to this server to make sure the communication is back online.any root cause for this??

Note: After OS installation (SLES 11 SP2 SAP version) a firmware update has done as well.

Your Assistance on this is highly appreciated.

2

Hi
That’s really a bugzilla (https://bugzilla.novell.com/index.cgi) or if
you have the option, raise an SR to get that looked at.

–
Cheers Malcolm °¿° (Linux Counter #276890)
openSUSE 12.2 (x86_64) Kernel 3.4.11-2.16-desktop
up 20:58, 3 users, load average: 0.03, 0.04, 0.05
CPU Intel i5 CPU M520@2.40GHz | Intel Arrandale GPU

3

Hi Malcolm,

Thanks for your early response on this matter. I will raise an SR to this.

4

Hi
Excellent :slight_smile: If you have any issues with the SR, please post back
details in the thread.

–
Cheers Malcolm °¿° (Linux Counter #276890)
openSUSE 12.2 (x86_64) Kernel 3.4.11-2.16-desktop
up 22:18, 4 users, load average: 0.11, 0.07, 0.06
CPU Intel i5 CPU M520@2.40GHz | Intel Arrandale GPU

5

Hi Malcolm,

Just now i was able to raise the SR to Novell. Thank you for your assistance on this matter. I will post back :slight_smile:

6

[QUOTE=lash04;9562]Hi Malcolm,

Just now i was able to raise the SR to Novell. Thank you for your assistance on this matter. I will post back :)[/QUOTE]

Hi lash04,
Any word back on this? This issue pops up on multiple SLES 11 SP2 servers in our environment.

From what I understand, it means the kernel is ‘tainted’. This article gives more info on what that means and how to decode the Taint flags. However, the flags and the logs themselves fail to give me further info on what is actually causing the taint. Could be a hardware issue or perhaps a driver/module issue.

7

Hi Ashby,

Yes got a reply from Novell. There is a new Maintenance-Kernel update release.You can apply that and they said these messages means no harm. In the meanwhile, please check whether you have done any firmware updates coz that can bring these issues too.

8

[QUOTE=lash04;9825]Hi Ashby,

Yes got a reply from Novell. There is a new Maintenance-Kernel update release.You can apply that and they said these messages means no harm. In the meanwhile, please check whether you have done any firmware updates coz that can bring these issues too.[/QUOTE]

Good to hear. Do you know which patch # that is? Or the date that patch was released?