kernel is 2.6.7-bk17 and today i got an oops again:

 kernel: nfsd: page allocation failure. order:5, mode:0xd0
 kernel: [<c0132cf1>] __alloc_pages+0x2d1/0x2e0
 kernel: [<c0132d18>] __get_free_pages+0x18/0x40
 kernel: [<c0135f29>] kmem_getpages+0x19/0xb0
 kernel: [<c0136b16>] cache_grow+0xb6/0x190
 kernel: [<c0136dcb>] cache_alloc_refill+0x1db/0x220
 kernel: [<c029dc60>] ip_local_deliver_finish+0x0/0x1d0
 kernel: [<c01371dc>] __kmalloc+0x5c/0x60
 kernel: [<c01fdd2e>] kmem_alloc+0x5e/0xf0
 kernel: [<c01db7e6>] xfs_iread_extents+0x66/0x110
 kernel: [<c029dc60>] ip_local_deliver_finish+0x0/0x1d0
 kernel: [<c01b62a9>] xfs_bmapi+0x1e9/0x1400
 kernel: [<c028343c>] sk_reset_timer+0xc/0x20
 kernel: [<c02ac0bb>] tcp_clean_rtx_queue+0x29b/0x3d0
 kernel: [<d08c931b>] ipt_do_table+0x2eb/0x500 [ip_tables]
 kernel: [<c02ac90d>] tcp_ack+0xdd/0x5d0
 kernel: [<c01b4c28>] xfs_bmap_do_search_extents+0xc8/0x400
 kernel: [<c029dc60>] ip_local_deliver_finish+0x0/0x1d0
 kernel: [<c01b4fbb>] xfs_bmap_search_extents+0x5b/0x80
 kernel: [<c01b6300>] xfs_bmapi+0x240/0x1400
 kernel: [<c01df6c6>] xfs_iomap+0x176/0x4a0
 kernel: [<c0163e1a>] iget_locked+0x6a/0xe0
 kernel: [<c01ff40e>] linvfs_get_block_core+0x9e/0x2a0
 kernel: [<c01de591>] xfs_iaccess+0xb1/0x210
 kernel: [<c01f7eaf>] xfs_access+0x3f/0x50
 kernel: [<c0204fe0>] linvfs_permission+0x0/0x20
 kernel: [<c01ff635>] linvfs_get_block+0x25/0x30
 kernel: [<c016add8>] do_mpage_readpage+0x248/0x330
 kernel: [<c0212a90>] radix_tree_node_alloc+0x10/0x50
 kernel: [<c0212ca6>] radix_tree_insert+0x76/0x110
 kernel: [<c012e57a>] add_to_page_cache+0x5a/0xb0
 kernel: [<c016afae>] mpage_readpages+0xee/0x140
 kernel: [<c01ff610>] linvfs_get_block+0x0/0x30
 kernel: [<c02a09b8>] ip_finish_output2+0xb8/0x1e0
 kernel: [<c02a0900>] ip_finish_output2+0x0/0x1e0
 kernel: [<c029224f>] nf_hook_slow+0x13f/0x160
 kernel: [<c01356f0>] read_pages+0x130/0x140
 kernel: [<c01ff610>] linvfs_get_block+0x0/0x30
 kernel: [<c0132937>] buffered_rmqueue+0xf7/0x1e0
 kernel: [<c0132abf>] __alloc_pages+0x9f/0x2e0
 kernel: [<c0135ab4>] do_page_cache_readahead+0x1a4/0x1d0
 kernel: [<c0135bc9>] page_cache_readahead+0xe9/0x1f0
 kernel: [<c012edfd>] do_generic_mapping_read+0xed/0x4d0
 kernel: [<c012f6eb>] generic_file_sendfile+0x6b/0x90
 kernel: [<d09770c0>] nfsd_read_actor+0x0/0xd0 [nfsd]
 kernel: [<c0205ae7>] xfs_sendfile+0xc7/0x1b0
 kernel: [<d09770c0>] nfsd_read_actor+0x0/0xd0 [nfsd]
 kernel: [<c020242a>] linvfs_sendfile+0x4a/0x60
 kernel: [<d09770c0>] nfsd_read_actor+0x0/0xd0 [nfsd]
 kernel: [<d09773b6>] nfsd_read+0x226/0x3e0 [nfsd]
 kernel: [<d09770c0>] nfsd_read_actor+0x0/0xd0 [nfsd]
 kernel: [<d097e04f>] nfsd3_proc_read+0xaf/0x170 [nfsd]
 kernel: [<d097fcf0>] nfs3svc_decode_readargs+0x0/0x190 [nfsd]
 kernel: [<d09736aa>] nfsd_dispatch+0x8a/0x1f0 [nfsd]
 kernel: [<d092fa53>] svc_authenticate+0xd3/0x120 [sunrpc]
 kernel: [<d092cefd>] svc_process+0x57d/0x610 [sunrpc]
 kernel: [<d0982560>] nfs3svc_release_fhandle+0x0/0x10 [nfsd]
 kernel: [<d097346b>] nfsd+0x1cb/0x380 [nfsd]
 kernel: [<d09732a0>] nfsd+0x0/0x380 [nfsd]
 kernel: [<c0101f7d>] kernel_thread_helper+0x5/0x18

this is debian/unstable (i386), gcc-3.4.0, xfsprogs-2.6.11-1.

(i sent a mail to linux-xfs, but i think bugzilla is the preferred location to
report bugs)