I'm suffering from random freezes that more or less match the above description. What I see in the logs is:

May 30 16:27:31 test-desktop kernel: [ 5425.833094] BUG: unable to handle kernel paging request at f7cea2bc
May 30 16:27:31 test-desktop kernel: [ 5425.833103] IP: [<c021a426>] __d_lookup+0x66/0x110
May 30 16:27:31 test-desktop kernel: [ 5425.833114] *pde = 3703c067 *pte = 00000000 
May 30 16:27:31 test-desktop kernel: [ 5425.833119] Oops: 0000 [#1] SMP 
May 30 16:27:31 test-desktop kernel: [ 5425.833123] last sysfs file: /sys/devices/pci0000:00/0000:00:0e.0/host2/target2:0:0/2:0:0:0/block/sdb/uevent
May 30 16:27:31 test-desktop kernel: [ 5425.833128] Modules linked in: usblp xt_limit xt_tcpudp ipt_LOG ipt_MASQUERADE xt_DSCP ipt_REJECT nf_conntrack_irc nf_conntrack_ftp xt_state nls_utf8 isofs nls_iso8859_1 nls_cp437 vfat fat snd_usb_audio snd_usb_lib gspca_stv06xx binfmt_misc snd_hda_codec_analog iptable_nat snd_wavefront nf_nat snd_cs4236 nf_conntrack_ipv4 snd_wss_lib nf_conntrack nf_defrag_ipv4 snd_opl3_lib snd_mpu401 snd_mpu401_uart snd_seq_dummy iptable_mangle snd_seq_oss snd_seq_midi snd_rawmidi snd_hda_intel iptable_filter snd_seq_midi_event snd_hda_codec snd_hwdep snd_pcm_oss snd_seq snd_mixer_oss ip_tables x_tables snd_seq_device snd_pcm gspca_zc3xx gspca_main nvidia(P) fbcon tileblit font bitblit softcursor ppdev snd_timer videodev v4l1_compat snd ns558 snd_page_alloc k8temp agpgart vga16fb vgastate i2c_nforce2 soundcore gameport parport_pc asus_atk0110 lp parport usb_storage usbhid hid ohci1394 ieee1394 forcedeth pata_amd sata_nv floppy
May 30 16:27:31 test-desktop kernel: [ 5425.833198] 
May 30 16:27:31 test-desktop kernel: [ 5425.833203] Pid: 2794, comm: udisks-daemon Tainted: P           (2.6.32-22-generic #33-Ubuntu) System Product Name
May 30 16:27:31 test-desktop kernel: [ 5425.833208] EIP: 0060:[<c021a426>] EFLAGS: 00010282 CPU: 0
May 30 16:27:31 test-desktop kernel: [ 5425.833212] EIP is at __d_lookup+0x66/0x110
May 30 16:27:31 test-desktop kernel: [ 5425.833215] EAX: 00002541 EBX: f7cea2bc ECX: 00000011 EDX: f2be63b8
May 30 16:27:31 test-desktop kernel: [ 5425.833218] ESI: e844b3b8 EDI: d87a1ef0 EBP: d87a1ea4 ESP: d87a1e80
May 30 16:27:31 test-desktop kernel: [ 5425.833222]  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
May 30 16:27:31 test-desktop kernel: [ 5425.833226] Process udisks-daemon (pid: 2794, ti=d87a0000 task=f69fd9b0 task.ti=d87a0000)
May 30 16:27:31 test-desktop kernel: [ 5425.833228] Stack:
May 30 16:27:31 test-desktop kernel: [ 5425.833230]  d87a1f3f d87a1ef0 00000001 00002541 e844b3b8 f2be63b8 00000504 e844b3b8
May 30 16:27:31 test-desktop kernel: [ 5425.833238] <0> d87a1ef0 d87a1eb8 c021a50c d87a1f3f 00000001 00000003 d87a1f08 c024cfa5
May 30 16:27:31 test-desktop kernel: [ 5425.833245] <0> ffffffff 00000000 0000000d d87a1f3f d87a1f4c c070016b 00000010 00000002
May 30 16:27:31 test-desktop kernel: [ 5425.833253] Call Trace:
May 30 16:27:31 test-desktop kernel: [ 5425.833259]  [<c021a50c>] ? d_lookup+0x3c/0x50
May 30 16:27:31 test-desktop kernel: [ 5425.833264]  [<c024cfa5>] ? proc_fill_cache+0x65/0x150
May 30 16:27:31 test-desktop kernel: [ 5425.833269]  [<c02168a0>] ? filldir64+0x0/0xf0
May 30 16:27:31 test-desktop kernel: [ 5425.833274]  [<c024eb5b>] ? proc_readfd_common+0xeb/0x1f0
May 30 16:27:31 test-desktop kernel: [ 5425.833279]  [<c0250af0>] ? proc_fd_instantiate+0x0/0x130
May 30 16:27:31 test-desktop kernel: [ 5425.833284]  [<c0250af0>] ? proc_fd_instantiate+0x0/0x130
May 30 16:27:31 test-desktop kernel: [ 5425.833288]  [<c02168a0>] ? filldir64+0x0/0xf0
May 30 16:27:31 test-desktop kernel: [ 5425.833293]  [<c01e6259>] ? handle_mm_fault+0x139/0x390
May 30 16:27:31 test-desktop kernel: [ 5425.833298]  [<c024ec97>] ? proc_readfd+0x17/0x20
May 30 16:27:31 test-desktop kernel: [ 5425.833302]  [<c0250af0>] ? proc_fd_instantiate+0x0/0x130
May 30 16:27:31 test-desktop kernel: [ 5425.833307]  [<c0216bd6>] ? vfs_readdir+0x96/0xb0
May 30 16:27:31 test-desktop kernel: [ 5425.833310]  [<c02168a0>] ? filldir64+0x0/0xf0
May 30 16:27:31 test-desktop kernel: [ 5425.833314]  [<c0216c59>] ? sys_getdents64+0x69/0xc0
May 30 16:27:31 test-desktop kernel: [ 5425.833319]  [<c01033ec>] ? syscall_call+0x7/0xb
May 30 16:27:31 test-desktop kernel: [ 5425.833322] Code: 45 dc 89 d0 35 01 00 37 9e d3 e8 31 d0 23 05 94 13 7a c0 c1 e0 02 03 05 9c 13 7a c0 8b 18 85 db 75 09 eb 6e 90 8b 1b 85 db 74 67 <8b> 03 0f 18 00 90 8d 53 ec 8b 45 e8 89 55 f0 39 42 20 75 e6 8b 
May 30 16:27:31 test-desktop kernel: [ 5425.833360] EIP: [<c021a426>] __d_lookup+0x66/0x110 SS:ESP 0068:d87a1e80
May 30 16:27:31 test-desktop kernel: [ 5425.833365] CR2: 00000000f7cea2bc
May 30 16:27:31 test-desktop kernel: [ 5425.833369] ---[ end trace aaa071149051d3bd ]---

Would you guys consider that a variant of the same bug? Does the above trace help?

Yoav