My computer has been running fine for a while with this kernel, but suddenly this happened (once). If more info is required, please ask, I'll do my best to provide all you need. BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff811e986f>] ext4_mb_good_group+0x5f/0x130 PGD 21ee03067 PUD 21ee09067 PMD 0 Oops: 0000 [#1] SMP CPU 1 Modules linked in: nvidia(P) snd_emu10k1 snd_rawmidi snd_ac97_codec ac97_bus snd_pcm snd_seq_device snd_timer snd_page_alloc snd_util_mem snd_hwdep snd soundcore [last unloaded: nvidia] Pid: 3119, comm: flush-252:2 Tainted: P O 3.2.12-gentoo #2 Gigabyte Technology Co., Ltd. GA-MA790X-UD3P/GA-MA790X-UD3P RIP: 0010:[<ffffffff811e986f>] [<ffffffff811e986f>] ext4_mb_good_group+0x5f/0x130 RSP: 0018:ffff8802230016d0 EFLAGS: 00010293 RAX: ffff880222170c00 RBX: 00000000000003f0 RCX: 0000000000000070 RDX: 0000000000000000 RSI: ffff880225106000 RDI: ffff880226116400 RBP: ffff880224a6a088 R08: 0000000000000007 R09: 0000000000002238 R10: 0000000000000003 R11: 0000000000100000 R12: 0000000000000000 R13: 0000000000000000 R14: 00000000000003f0 R15: 0000000000000001 FS: 00007fdc09923720(0000) GS:ffff88022fc80000(0000) knlGS:00000000f6f21b70 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000000 CR3: 0000000222305000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process flush-252:2 (pid: 3119, threadinfo ffff880223000000, task ffff880223f74500) Stack: 0000000000011200 ffff880224a6a088 00000000000003c0 ffff880224a6a088 0000000000000000 00000000000003c0 ffff880226116400 ffffffff811ebd90 0000000000000086 ffffffff81051484 ffff880226114400 0000000000000000 Call Trace: [<ffffffff811ebd90>] ? ext4_mb_regular_allocator+0x170/0x3c0 [<ffffffff81051484>] ? gart_map_sg+0x404/0x440 [<ffffffff811ed5aa>] ? ext4_mb_new_blocks+0x2ea/0x3e0 [<ffffffff811f1eda>] ? ext4_alloc_branch+0x3aa/0x5a0 [<ffffffff811f1b07>] ? ext4_get_branch+0x107/0x130 [<ffffffff811f2b27>] ? ext4_ind_map_blocks+0x247/0x620 [<ffffffff811cb53d>] ? ext4_map_blocks+0xed/0x2c0 [<ffffffff811cf435>] ? mpage_da_map_and_submit+0xc5/0x470 [<ffffffff811d9998>] ? ext4_journal_start_sb+0x68/0x160 [<ffffffff811cfeab>] ? ext4_da_writepages+0x28b/0x470 [<ffffffff8112dd6b>] ? writeback_single_inode+0x16b/0x350 [<ffffffff8112e3b5>] ? writeback_sb_inodes+0x1e5/0x290 [<ffffffff8112e4f6>] ? __writeback_inodes_wb+0x96/0xc0 [<ffffffff8112e72b>] ? wb_writeback+0x20b/0x220 [<ffffffff811229b1>] ? get_nr_inodes+0x41/0x60 [<ffffffff8112eaca>] ? wb_do_writeback+0x1aa/0x1c0 [<ffffffff8112eb62>] ? bdi_writeback_thread+0x82/0x150 [<ffffffff8112eae0>] ? wb_do_writeback+0x1c0/0x1c0 [<ffffffff8112eae0>] ? wb_do_writeback+0x1c0/0x1c0 [<ffffffff81097146>] ? kthread+0x96/0xa0 [<ffffffff8165cb34>] ? kernel_thread_helper+0x4/0x10 [<ffffffff810970b0>] ? kthread_worker_fn+0x120/0x120 [<ffffffff8165cb30>] ? gs_change+0xb/0xb Code: 28 02 00 00 44 8b a0 e0 02 00 00 41 d3 e8 48 8b 48 38 45 89 c0 4a 8b 04 c6 48 ff c9 21 d9 83 fa 03 4c 8b 2c c8 0f 87 c8 00 00 00 <49> 8b 45 00 a8 01 75 61 41 8b 45 14 41 8b 4d 18 85 c0 74 6d 85 RIP [<ffffffff811e986f>] ext4_mb_good_group+0x5f/0x130 RSP <ffff8802230016d0> CR2: 0000000000000000 ---[ end trace 1e3ba02eddf7210a ]---
Please duplicate the problem without proprietary modules loaded otherwise we can't really do much with it. If you can't duplicate it that way then report it to Nvidia instead.