kernel crash - CIFS client unstable on faulty network conditions

Hi,

We are using:

kernel 2.6.31-5
samba 3.4.2

to mount CIFS shares over DFS.

Everything works fine under normal conditions. However if some server(s) is/are unreachable we end up with a kernel crash that locks up the machine.

Kernel logs can be seen below.

Any comment?

Cheers
Gustavo


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Dec  2 15:13:39 CGDWX08027093 klogd:  CIFS VFS: No response for cmd 114 mid 1
Dec  2 15:13:39 CGDWX08027093 klogd: BUG: unable to handle kernel NULL pointer dereference at 00000020
Dec  2 15:13:39 CGDWX08027093 klogd: IP: [<f847e804>] cifs_put_smb_ses+0x14/0xd0 [cifs]
Dec  2 15:13:39 CGDWX08027093 klogd: *pde = 00000000 
Dec  2 15:13:39 CGDWX08027093 klogd: Oops: 0000 [#1] SMP 
Dec  2 15:13:39 CGDWX08027093 klogd: last sysfs file: /sys/devices/pci0000:00/0000:00:19.0/net/eth0/ifindex
Dec  2 15:13:39 CGDWX08027093 klogd: Modules linked in: nls_utf8 nls_iso8859_1 cifs i915 drm i2c_algo_bit i2c_core af_packet ipv6 binfmt_misc loop dm_mirror dm_region_hash dm_log dm_mod cpufreq_ondemand cpufreq_conservative cpufreq_powersave acpi_cpufreq freq_table snd_hda_codec_analog snd_hda_intel snd_hda_codec snd_hwdep snd_seq_dummy snd_seq_oss snd_seq_midi_event snd_seq snd_seq_device snd_pcm_oss snd_pcm snd_timer snd_mixer_oss ehci_hcd snd e1000e heci(C) soundcore snd_page_alloc iTCO_wdt iTCO_vendor_support pcspkr uhci_hcd processor floppy button evdev video wmi output tpm_infineon tpm tpm_bios thermal sg usbcore ide_generic ata_generic ide_pci_generic ide_gd_mod ide_core pata_acpi ahci ata_piix libata sd_mod scsi_mod crc_t10dif ext3 jbd
Dec  2 15:13:39 CGDWX08027093 klogd: 
Dec  2 15:13:39 CGDWX08027093 klogd: Pid: 3511, comm: mount.cifs Tainted: G        WC (2.6.31.5-desktop-1xcm #1) HP Compaq dc7900 Small Form Factor
Dec  2 15:13:39 CGDWX08027093 klogd: EIP: 0060:[<f847e804>] EFLAGS: 00010282 CPU: 1
Dec  2 15:13:39 CGDWX08027093 klogd: EIP is at cifs_put_smb_ses+0x14/0xd0 [cifs]
Dec  2 15:13:39 CGDWX08027093 klogd: EAX: 00000000 EBX: f5e64400 ECX: f5e64400 EDX: f5e65600
Dec  2 15:13:39 CGDWX08027093 klogd: ESI: 00000079 EDI: 00000000 EBP: f5dc1dfc ESP: f5dc1de0
Dec  2 15:13:39 CGDWX08027093 klogd:  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Dec  2 15:13:39 CGDWX08027093 klogd: Process mount.cifs (pid: 3511, ti=f5dc0000 task=f61ca550 task.ti=f5dc0000)
Dec  2 15:13:39 CGDWX08027093 klogd: Stack:
Dec  2 15:13:39 CGDWX08027093 klogd:  00000000 f5dc1dfc f848e101 f5dc1dfc f5e64400 00000079 00000000 f5dc1e20
Dec  2 15:13:39 CGDWX08027093 klogd: <0> f847e957 f8481193 00000000 c16bb260 f8481193 ffffff90 f614b000 f5e64400
Dec  2 15:13:39 CGDWX08027093 klogd: <0> f5dc1eb8 f84811a6 f5f9e950 f849d2f8 f5e64430 00000000 c0701028 c0701038
Dec  2 15:13:39 CGDWX08027093 klogd: Call Trace:
Dec  2 15:13:39 CGDWX08027093 klogd:  [<f848e101>] ? tconInfoFree+0x61/0x90 [cifs]
Dec  2 15:13:39 CGDWX08027093 klogd:  [<f847e957>] ? cifs_put_tcon+0x97/0xd0 [cifs]
Dec  2 15:13:39 CGDWX08027093 klogd:  [<f8481193>] ? cifs_mount+0x4e3/0x2570 [cifs]
Dec  2 15:13:39 CGDWX08027093 klogd:  [<f8481193>] ? cifs_mount+0x4e3/0x2570 [cifs]
Dec  2 15:13:39 CGDWX08027093 klogd:  [<f84811a6>] ? cifs_mount+0x4f6/0x2570 [cifs]
Dec  2 15:13:39 CGDWX08027093 klogd:  [<f8473df4>] ? cifs_get_sb+0x124/0x2c0 [cifs]
Dec  2 15:13:39 CGDWX08027093 klogd:  [<c01e4aae>] ? vfs_kern_mount+0x5e/0x120
Dec  2 15:13:39 CGDWX08027093 klogd:  [<c01e4bce>] ? do_kern_mount+0x3e/0xe0
Dec  2 15:13:39 CGDWX08027093 klogd:  [<c01fb376>] ? do_mount+0x446/0x7d0
Dec  2 15:13:39 CGDWX08027093 klogd:  [<c01f969d>] ? copy_mount_options+0xad/0x130
Dec  2 15:13:39 CGDWX08027093 klogd:  [<c01fb78c>] ? sys_mount+0x8c/0xb0
Dec  2 15:13:39 CGDWX08027093 klogd:  [<c0103cfb>] ? sysenter_do_call+0x12/0x28
Dec  2 15:13:39 CGDWX08027093 klogd: Code: a4 00 00 00 85 d2 74 bc b8 09 00 00 00 e8 85 30 cd c7 5b 5d c3 66 90 55 89 e5 83 ec 1c 89 5d f4 89 75 f8 89 7d fc 0f 1f 44 00 00 <8b> 70 20 89 c3 b8 20 fd 4a f8 e8 4d 35 f9 c7 8b 43 24 83 e8 01 
Dec  2 15:13:39 CGDWX08027093 klogd: EIP: [<f847e804>] cifs_put_smb_ses+0x14/0xd0 [cifs] SS:ESP 0068:f5dc1de0
Dec  2 15:13:39 CGDWX08027093 klogd: CR2: 0000000000000020
Dec  2 15:13:39 CGDWX08027093 klogd: ---[ end trace 93d72a36b9146f24 ]---
Dec  2 15:14:01 CGDWX08027093 CROND[6710]: (root) CMD (   /usr/share/msec/promisc_check.sh)
Dec  2 15:14:10 CGDWX08027093 klogd: BUG: unable to handle kernel NULL pointer dereference at (null)
Dec  2 15:14:10 CGDWX08027093 klogd: IP: [<f847f91c>] cifs_demultiplex_thread+0x37c/0xc50 [cifs]
Dec  2 15:14:10 CGDWX08027093 klogd: *pde = 00000000 
Dec  2 15:14:10 CGDWX08027093 klogd: Oops: 0000 [#2] SMP 
Dec  2 15:14:10 CGDWX08027093 klogd: last sysfs file: /sys/devices/pci0000:00/0000:00:19.0/net/eth0/ifindex
Dec  2 15:14:10 CGDWX08027093 klogd: Modules linked in: nls_utf8 nls_iso8859_1 cifs i915 drm i2c_algo_bit i2c_core af_packet ipv6 binfmt_misc loop dm_mirror dm_region_hash dm_log dm_mod cpufreq_ondemand cpufreq_conservative cpufreq_powersave acpi_cpufreq freq_table snd_hda_codec_analog snd_hda_intel snd_hda_codec snd_hwdep snd_seq_dummy snd_seq_oss snd_seq_midi_event snd_seq snd_seq_device snd_pcm_oss snd_pcm snd_timer snd_mixer_oss ehci_hcd snd e1000e heci(C) soundcore snd_page_alloc iTCO_wdt iTCO_vendor_support pcspkr uhci_hcd processor floppy button evdev video wmi output tpm_infineon tpm tpm_bios thermal sg usbcore ide_generic ata_generic ide_pci_generic ide_gd_mod ide_core pata_acpi ahci ata_piix libata sd_mod scsi_mod crc_t10dif ext3 jbd
Dec  2 15:14:10 CGDWX08027093 klogd: 
Dec  2 15:14:10 CGDWX08027093 klogd: Pid: 5120, comm: cifsd Tainted: G      D WC (2.6.31.5-desktop-1xcm #1) HP Compaq dc7900 Small Form Factor
Dec  2 15:14:10 CGDWX08027093 klogd: EIP: 0060:[<f847f91c>] EFLAGS: 00010216 CPU: 1
Dec  2 15:14:10 CGDWX08027093 klogd: EIP is at cifs_demultiplex_thread+0x37c/0xc50 [cifs]
Dec  2 15:14:10 CGDWX08027093 klogd: EAX: f84afd20 EBX: f5e64400 ECX: f6c38000 EDX: 00000000
Dec  2 15:14:10 CGDWX08027093 klogd: ESI: f5e64460 EDI: f5e64408 EBP: f5f73fb8 ESP: f5f73f40
Dec  2 15:14:10 CGDWX08027093 klogd:  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Dec  2 15:14:10 CGDWX08027093 klogd: Process cifsd (pid: 5120, ti=f5f72000 task=f5f5eff0 task.ti=f5f72000)
Dec  2 15:14:10 CGDWX08027093 klogd: Stack:
Dec  2 15:14:10 CGDWX08027093 klogd:  00000000 00000004 00000000 743594af f5e64448 c1f9a420 f5e64460 f61ca550
Dec  2 15:14:10 CGDWX08027093 klogd: <0> f5fd0000 f5dbb340 f6b46e00 f5f5eff0 00f5f270 c1f9a420 00000001 c012e588
Dec  2 15:14:10 CGDWX08027093 klogd: <0> 74359c99 83000001 00000003 00000000 f5f73fa4 00000001 00000000 00000000
Dec  2 15:14:10 CGDWX08027093 klogd: Call Trace:
Dec  2 15:14:10 CGDWX08027093 klogd:  [<c012e588>] ? __wake_up_common+0x48/0x70
Dec  2 15:14:10 CGDWX08027093 klogd:  [<c013218e>] ? complete+0x4e/0x60
Dec  2 15:14:10 CGDWX08027093 klogd:  [<f847f5a0>] ? cifs_demultiplex_thread+0x0/0xc50 [cifs]
Dec  2 15:14:10 CGDWX08027093 klogd:  [<c0159e14>] ? kthread+0x84/0x90
Dec  2 15:14:10 CGDWX08027093 klogd:  [<c0159d90>] ? kthread+0x0/0x90
Dec  2 15:14:10 CGDWX08027093 klogd:  [<c0104947>] ? kernel_thread_helper+0x7/0x10
Dec  2 15:14:10 CGDWX08027093 klogd: Code: 4d a0 3b 4b 60 74 17 f6 05 04 fd 4a f8 01 0f 85 4e 04 00 00 b8 b0 b3 00 00 e8 71 e9 cc c7 b8 20 fd 4a f8 e8 57 22 f9 c7 8b 53 08 <8b> 02 0f 18 00 90 39 fa 74 15 66 90 c7 42 20 00 00 00 00 89 c2 
Dec  2 15:14:10 CGDWX08027093 klogd: EIP: [<f847f91c>] cifs_demultiplex_thread+0x37c/0xc50 [cifs] SS:ESP 0068:f5f73f40
Dec  2 15:14:10 CGDWX08027093 klogd: CR2: 0000000000000000
Dec  2 15:14:10 CGDWX08027093 klogd: ---[ end trace 93d72a36b9146f25 ]---

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Angulo Sólido - Tecnologias de Informação
http://angulosolido.pt