Binary package hint: ubuntu's linux-image-2.6.15-29-server
Bug also raised with ubuntu.com: Bug #153855
https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.15/+bug/153855

I get a lock up when using CIFS.
The following output was captured via the console port.
During the lock up, ping works to the box, but sshd or any other higher level service does not work.

[42951888.400000] CIFS VFS: Calculated size 0x27 vs actual length 0x48
[42951888.420000] CIFS VFS: bad smb size detected for Mid=15525
[42951889.400000] CIFS VFS: Calculated size 0x27 vs actual length 0x48
[42951889.420000] CIFS VFS: bad smb size detected for Mid=15625
[42951953.200000] CIFS VFS: Calculated size 0x27 vs actual length 0x48
[42951953.220000] CIFS VFS: bad smb size detected for Mid=21731
[42955494.580000] CIFS VFS: Calculated size 0x27 vs actual length 0x48
[42955494.600000] CIFS VFS: bad smb size detected for Mid=16670
[42955496.100000] CIFS VFS: Calculated size 0x27 vs actual length 0x48
[42955496.120000] CIFS VFS: bad smb size detected for Mid=17181
[42955584.780000] CIFS VFS: Calculated size 0x27 vs actual length 0x48
[42955584.800000] CIFS VFS: bad smb size detected for Mid=48076
[42957738.790000] BUG: soft lockup detected on CPU#0!
[42957738.790000]
[42957738.790000] Pid: 4505, comm: rsync
[42957738.790000] EIP: 0060:[<c017cd3a>] CPU: 0
[42957738.790000] EIP is at generic_fillattr+0x8a/0xb0
[42957738.790000] EFLAGS: 00000202 Not tainted (2.6.15-29-server)
[42957738.790000] EAX: 00000009 EBX: 00320000 ECX: 00000009 EDX: 00000009
[42957738.790000] ESI: 00000000 EDI: dda5e378 EBP: f7541f70 DS: 007b ES: 007b
[42957738.790000] CR0: 8005003b CR2: b7966004 CR3: 1fae1820 CR4: 000006b0
[42957738.790000] [<f8b2c730>] cifs_getattr+0x30/0x40 [cifs]
[42957738.790000] [<c017cf49>] vfs_fstat+0x39/0x50
[42957738.790000] [<c017d618>] sys_fstat64+0x18/0x40
[42957738.790000] [<c01718e6>] do_sys_open+0xd6/0x100
[42957738.790000] [<c0103313>] sysenter_past_esp+0x54/0x75
[42957748.800000] BUG: soft lockup detected on CPU#0!
[42957748.800000]
[42957748.800000] Pid: 4505, comm: rsync
[42957748.800000] EIP: 0060:[<c017cd2a>] CPU: 0
[42957748.800000] EIP is at generic_fillattr+0x7a/0xb0
[42957748.800000] EFLAGS: 00000202 Not tainted (2.6.15-29-server)
[42957748.800000] EAX: 00000009 EBX: 00320000 ECX: 00000009 EDX: 00000001
[42957748.800000] ESI: 00000000 EDI: dda5e378 EBP: f7541f70 DS: 007b ES: 007b
[42957748.800000] CR0: 8005003b CR2: b7966004 CR3: 1fae1820 CR4: 000006b0
[42957748.800000] [<f8b2c730>] cifs_getattr+0x30/0x40 [cifs]
[42957748.800000] [<c017cf49>] vfs_fstat+0x39/0x50
[42957748.800000] [<c017d618>] sys_fstat64+0x18/0x40
[42957748.800000] [<c01718e6>] do_sys_open+0xd6/0x100
[42957748.800000] [<c0103313>] sysenter_past_esp+0x54/0x75
[42957758.810000] BUG: soft lockup detected on CPU#0!
[42957758.810000]
[42957758.810000] Pid: 4505, comm: rsync
[42957758.810000] EIP: 0060:[<c017cd25>] CPU: 0
[42957758.810000] EIP is at generic_fillattr+0x75/0xb0
[42957758.810000] EFLAGS: 00000202 Not tainted (2.6.15-29-server)
[42957758.810000] EAX: 00000009 EBX: 00320000 ECX: 00000009 EDX: 00000001
[42957758.810000] ESI: 00000000 EDI: dda5e378 EBP: f7541f70 DS: 007b ES: 007b
[42957758.810000] CR0: 8005003b CR2: b7966004 CR3: 1fae1820 CR4: 000006b0
[42957758.810000] [<f8b2c730>] cifs_getattr+0x30/0x40 [cifs]
[42957758.810000] [<c017cf49>] vfs_fstat+0x39/0x50
[42957758.810000] [<c017d618>] sys_fstat64+0x18/0x40
[42957758.810000] [<c01718e6>] do_sys_open+0xd6/0x100
[42957758.810000] [<c0103313>] sysenter_past_esp+0x54/0x75
[42957768.820000] BUG: soft lockup detected on CPU#0!
[42957768.820000]
[42957768.820000] Pid: 4505, comm: rsync
[42957768.820000] EIP: 0060:[<c017cd30>] CPU: 0
[42957768.820000] EIP is at generic_fillattr+0x80/0xb0
[42957768.820000] EFLAGS: 00000202 Not tainted (2.6.15-29-server)
[42957768.820000] EAX: 00000009 EBX: 00320000 ECX: 00000009 EDX: 00000001
[42957768.820000] ESI: 00000000 EDI: dda5e378 EBP: f7541f70 DS: 007b ES: 007b
[42957768.820000] CR0: 8005003b CR2: b7966004 CR3: 1fae1820 CR4: 000006b0
[42957768.820000] [<f8b2c730>] cifs_getattr+0x30/0x40 [cifs]
[42957768.820000] [<c017cf49>] vfs_fstat+0x39/0x50
[42957768.820000] [<c017d618>] sys_fstat64+0x18/0x40
[42957768.820000] [<c01718e6>] do_sys_open+0xd6/0x100
[42957768.820000] [<c0103313>] sysenter_past_esp+0x54/0x75

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