Comment 12 for bug 1091169

It took me some hours to set up a vm and working around a few bugs (eg. bug 935585), but finally I got the mainline kernel working.

[ 1096.823058] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 1096.823064] IP: [< (null)>] (null)
[ 1096.823067] PGD 17c37067 PUD 929e067 PMD 0
[ 1096.823069] Oops: 0010 [#1] SMP
[ 1096.823072] Modules linked in: arc4 md4 nls_utf8 cifs fscache nf_conntrack_ipv6 nf_defrag_ipv6 xt_tcpudp nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack vboxvideo(OF) drm ip6table_filter ip6_tables iptable_filter ip_tables x_tables bnep rfcomm bluetooth lp snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_page_alloc snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device joydev snd_timer hid_generic psmouse usbhid snd ppdev hid serio_raw soundcore parport_pc i2c_piix4 parport microcode mac_hid e1000
[ 1096.823092] CPU 0
[ 1096.823096] Pid: 7375, comm: mount.cifs Tainted: GF O 3.8.0-030800rc2-generic #201301022235 innotek GmbH VirtualBox/VirtualBox
[ 1096.823098] RIP: 0010:[<0000000000000000>] [< (null)>] (null)
[ 1096.823100] RSP: 0018:ffff88000929dc70 EFLAGS: 00010246
[ 1096.823101] RAX: ffffffffa02a56c0 RBX: ffff88000d559e40 RCX: 0000000000000000
[ 1096.823102] RDX: 0000000000000000 RSI: ffff88000d559e40 RDI: ffff880007142350
[ 1096.823103] RBP: ffff88000929dc98 R08: ffff88001fc17380 R09: ffffc90000000000
[ 1096.823104] R10: ffffffffa02818b5 R11: 0000000007e44712 R12: ffff88000d5599c0
[ 1096.823105] R13: ffff88001b6c2651 R14: ffff88001b6c2640 R15: ffff8800071423f8
[ 1096.823109] FS: 00007fd220cfe740(0000) GS:ffff88001fc00000(0000) knlGS:0000000000000000
[ 1096.823110] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 1096.823111] CR2: 0000000000000000 CR3: 0000000003d19000 CR4: 00000000000006f0
[ 1096.823114] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1096.823120] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 1096.823122] Process mount.cifs (pid: 7375, threadinfo ffff88000929c000, task ffff880000ff2e40)
[ 1096.823122] Stack:
[ 1096.823157] ffffffff811a266d ffff88000d5599c0 ffff88001b6c2651 ffff88001b6c2640
[ 1096.823160] 0000000000000000 ffff88000929dcc8 ffffffff811a2ad8 ffff88001b6c2651
[ 1096.823162] 01ff88000d5599c0 ffff88001b6c2651 ffff88000d5599c0 ffff88000929dd08
[ 1096.823164] Call Trace:
[ 1096.823169] [<ffffffff811a266d>] ? lookup_real+0x1d/0x60
[ 1096.823171] [<ffffffff811a2ad8>] __lookup_hash+0x38/0x50
[ 1096.823174] [<ffffffff811a6b7e>] lookup_one_len+0xce/0x120
[ 1096.823181] [<ffffffffa026d7e1>] cifs_get_root+0x111/0x190 [cifs]
[ 1096.823186] [<ffffffffa026d9e2>] cifs_do_mount+0x182/0x270 [cifs]
[ 1096.823189] [<ffffffff8119c623>] mount_fs+0x43/0x1b0
[ 1096.823191] [<ffffffff811b73d6>] vfs_kern_mount+0x76/0x120
[ 1096.823193] [<ffffffff811b8851>] do_new_mount+0xb1/0x1e0
[ 1096.823195] [<ffffffff811ba066>] do_mount+0x1b6/0x1f0
[ 1096.823197] [<ffffffff811ba130>] sys_mount+0x90/0xe0
[ 1096.823200] [<ffffffff816f14dd>] system_call_fastpath+0x1a/0x1f
[ 1096.823201] Code: Bad RIP value.
[ 1096.823205] RIP [< (null)>] (null)
[ 1096.823206] RSP <ffff88000929dc70>
[ 1096.823207] CR2: 0000000000000000
[ 1096.823210] ---[ end trace 44c55e75aa8302d1 ]---