Hi, Right after I copy a bunch of files from the NFS server to the client, I tried to diff the local files against the files on the server (I suppose that it should be "diff"ing the local files against the files in the cache instead). It then crashes on cachefile_read_or_alloc_page. Here are the error messages: Dec 10 16:41:37 GD008 kernel: BUG: unable to handle kernel NULL pointer dereference at virtual address 0000002c Dec 10 16:41:37 GD008 kernel: printing eip: Dec 10 16:41:37 GD008 kernel: e006ee6a Dec 10 16:41:37 GD008 kernel: *pde = 17948067 Dec 10 16:41:37 GD008 kernel: Oops: 0000 [#1] Dec 10 16:41:37 GD008 kernel: Modules linked in: server test snd_intel8x0 snd_ac97_codec snd_ac97_bus snd_seq_dummy snd_seq_oss snd_seq_midi_event snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss snd_pcm ehci_hcd uhci_hcd snd_timer snd i2c_i810 soundcore i2c_i801 i2c_algo_bit snd_page_alloc i2c_core 8139too e1000 pcnet32 b44 tg3 e100 3c59x mii ext3 jbd nfs cachefiles fscache lockd nfs_acl sunrpc Dec 10 16:41:37 GD008 kernel: CPU: 0 Dec 10 16:41:37 GD008 kernel: EIP: 0060:[<e006ee6a>] Not tainted VLI Dec 10 16:41:37 GD008 kernel: EFLAGS: 00010246 (2.6.17-rc6 #146) Dec 10 16:41:37 GD008 kernel: EIP is at cachefiles_read_or_alloc_page+0x3cb/0x483 [cachefiles] Dec 10 16:41:37 GD008 kernel: eax: 00000000 ebx: dd10f180 ecx: dd10db00 edx: c10c0480 Dec 10 16:41:37 GD008 kernel: esi: d34758c0 edi: dd10f180 ebp: c10c0480 esp: d850bd40 Dec 10 16:41:37 GD008 kernel: ds: 007b es: 007b ss: 0068 Dec 10 16:41:37 GD008 kernel: Process diff (pid: 1719, threadinfo=d850b000 task=df771a90) Dec 10 16:41:37 GD008 kernel: Stack: 00000164 00000000 e013d1a0 e0147cc9 c12abb00 dd10f180 d0b56080 d850bda0 Dec 10 16:41:37 GD008 kernel: dd1ad120 00000000 00000000 00000000 c10c0480 d0caf174 d0caf140 00000000 Dec 10 16:41:37 GD008 kernel: c6020e40 dd1ad100 00000000 e0148ccf 00000001 00000001 dd1ad030 00000164 Dec 10 16:41:37 GD008 kernel: Call Trace: Dec 10 16:41:37 GD008 kernel: <e0147cc9> nfs_readpage_from_fscache_complete+0x0/0x36 [nfs] <e0148ccf> nfs_wait_on_requests_locked+0x90/0xa2 [nfs] Dec 10 16:41:37 GD008 kernel: <e0028888> __fscache_read_or_alloc_page+0xa8/0xe6 [fscache] <e0147cc9> nfs_readpage_from_fscache_complete+0x0/0x36 [nfs] Dec 10 16:41:37 GD008 kernel: <e0148310> nfs_readpage+0x128/0x604 [nfs] <c0138e94> add_to_page_cache_lru+0xd/0x20 Dec 10 16:41:37 GD008 kernel: <c0139140> do_generic_mapping_read+0x201/0x400 <c0139ac7> __generic_file_aio_read+0x148/0x18f Dec 10 16:41:37 GD008 kernel: <c0138a81> file_read_actor+0x0/0xe0 <c0139b49> generic_file_aio_read+0x3b/0x42 Dec 10 16:41:37 GD008 kernel: <c0152317> do_sync_read+0xb8/0xf3 <c0129383> autoremove_wake_function+0x0/0x2d Dec 10 16:41:37 GD008 kernel: <c015225f> do_sync_read+0x0/0xf3 <c0152bde> vfs_read+0x9f/0x13e Dec 10 16:41:37 GD008 kernel: <c0152f45> sys_read+0x3c/0x63 <c01029ef> sysenter_past_esp+0x54/0x75 Dec 10 16:41:37 GD008 kernel: Code: e8 7f 73 0a e0 31 c9 8b 54 24 7c 8b 44 24 10 ff 54 24 0c eb 04 85 ed 74 07 89 e8 e8 39 02 0d e0 8b 5c 24 14 8b 44 24 24 8b 4b 18 <8b> 50 2c 8b 41 28 8b 58 2c 85 db 74 05 8b 41 34 ff d3 8b 44 24 Dec 10 16:41:37 GD008 kernel: EIP: [<e006ee6a>] cachefiles_read_or_alloc_page+0x3cb/0x483 [cachefiles] SS:ESP 0068:d850bd40 Derek
