apport information
** Tags added: apport-collected
** Description changed:
Currently latest Ubuntu Linux kernel image has a a bug, probably a race
condition, which happens when there are multiple kerberos nfs4 mounts in
/etc/fstab. This does not happen on every boot, so to reproduce this you
probably need a few retries. This happens using the current Ubuntu Linux
kernel in 14.04:
# cat /proc/version_signature
Ubuntu 3.13.0-35.62-generic 3.13.11.6
Apparently you need to have _multiple_ kerberos NFS4 mounts in
/etc/fstab to trigger this:
xx.helsinki.fi:/root_vdm_3/fshome1/u1 /home/ad/fshome1/u1 nfs4
sec=krb5,rw,bg,hard 0 0
xx.helsinki.fi:/root_vdm_3/fshome2/u2 /home/ad/fshome2/u2 nfs4
sec=krb5,rw,bg,hard 0 0
xx.helsinki.fi:/root_vdm_3/fshome3/u3 /home/ad/fshome3/u3 nfs4
sec=krb5,rw,bg,hard 0 0
xx.helsinki.fi:/root_vdm_3/fshome4/u4 /home/ad/fshome4/u4 nfs4
sec=krb5,rw,bg,hard 0 0
xx.helsinki.fi:/root_vdm_3/fshome5/u5 /home/ad/fshome5/u5 nfs4
sec=krb5,rw,bg,hard 0 0
xx.helsinki.fi:/root_vdm_3/fshome6/u6 /home/ad/fshome6/u6 nfs4
sec=krb5,rw,bg,hard 0 0
When this happens we get a kernel stack trace (complete trace included),
which starts like this:
[ 19.999751] gss_pipe_downcall: bad return from gss_fill_context: -4
[ 19.999779] [ cut here ]
[ 19.999791] kernel BUG at
/build/buildd/linux-3.13.0/net/sunrpc/auth_gss/auth_gss.c:735!
[ 19.999796] invalid opcode: [#1] SMP
[ 19.999802] Modules linked in: arc4(+) des_generic cmac xcbc nfsv4 rmd160
crypto_null af_key xfrm_algo dm_crypt snd_hda_codec_realtek gpio_ich hp_wmi
sparse_keymap snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_page_alloc
snd_seq_midi snd_seq_midi_event snd_rawmidi coretemp dm_multipath snd_seq
kvm_intel scsi_dh kvm snd_seq_device bnep serio_raw rfcomm snd_timer bluetooth
lpc_ich snd soundcore tpm_infineon mei_me mei mac_hid parport_pc ppdev lp
parport binfmt_misc rpcsec_gss_krb5 nfsd auth_rpcgss nfs_acl nfs lockd sunrpc
fscache dm_mirror dm_region_hash dm_log hid_generic usbhid hid nouveau mxm_wmi
video i2c_algo_bit ttm e1000e drm_kms_helper ahci psmouse libahci drm wmi ptp
pps_core
When this has happened, rpc.gssd gets stuck in D state:
# ps aux|grep gssd
root 452 0.0 0.0 0 0 ?Ds 13:18 0:00 [rpc.gssd]
Also NFS4 mounts will fail, with an error message which does not tell
what is actually going on:
root@do0-kukad211-07:~# mount -a -t nfs4
mount.nfs4: access denied by server while mounting
.helsinki.fi:/root_vdm_3/fshome1/u1
mount.nfs4: access denied by server while mounting
.helsinki.fi:/root_vdm_3/fshome2/u2
mount.nfs4: access denied by server while mounting
.helsinki.fi:/root_vdm_3/fshome3/u3
mount.nfs4: access denied by server while mounting
.helsinki.fi:/root_vdm_3/fshome4/u4
mount.nfs4: access denied by server while mounting
..helsinki.fi:/root_vdm_3/fshome5/u5
mount.nfs4: access denied by server while mounting
.helsinki.fi:/root_vdm_3/fshome6/u6
This also happened on Ubuntu 12.04, so the bug is probably old. There is
a bug report, which is (IMHO) incorrectly reported against nfs-utils:
https://bugs.launchpad.net/ubuntu/+source/nfs-utils/+bug/1046762
- We will fix this by removing the NFS mounts from fstab and doing them
- sequentially in startup scripts, but it would be nice if the kernel race
- would be fixed too.
+ We will fix this by removing the NFS mounts from fstab and doing them
sequentially in startup scripts, but it would be nice if the kernel race would
be fixed too.
+ ---
+ ApportVersion: 2.14.1-0ubuntu3.3
+ Architecture: amd64
+ AudioDevicesInUse:
+ USERPID ACCESS COMMAND
+ /dev/snd/controlC0: lightdm2698 F pulseaudio
+ /dev/snd/seq:timidity 2607 F timidity
+ CRDA: Error: [Errno 2] No such file or directory
+ CurrentDmesg:
+ [ 23.980615] init: gdm main process (1881) killed by TERM signal
+ [ 25.395448] init: plymouth-upstart-bridge main process ended, respawning
+ [ 25.402287] init: plymouth-upstart-bridge main process (2248) terminated
with status 1
+ [ 25.402298] init: plymouth-upstart-bridge main process ended, respawning
+ [ 27.805918] init: plymouth-stop pre-start process (2612) terminated with
status 1
+ DistroRelease: Ubuntu 14.04
+ HibernationDevice: RESUME=UUID=c7fe0bc6-4712-4a0e-9f10-9ade6280a12e
+ IwConfig:
+ eth0 no wireless extensions.
+
+ lono wireless extensions.
+ MachineType: Hewlett-Packard HP Compaq 8000 Elite CMT PC
+ Package: linux (not installed)
+ ProcFB: 0 nouveaufb
+ ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-35-generic
root=UUID=268aac80-328a-4ab2-9e21-f38b9897ba79 ro adhome quiet splash
vt.handoff=7
+ ProcVersionSignature: Ubuntu 3.13.0-35.62-generic 3.13.11.6
+ PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No
PulseAudio daemon running, or not r