Dec  1 13:14:52 ph4 kernel: BUG: unable to handle kernel NULL pointer dereference at 0000000000000d48
Dec  1 13:14:52 ph4 kernel: IP: [<ffffffffa0302044>] radeon_fence_signaled+0x44/0x90 [radeon]
Dec  1 13:14:52 ph4 kernel: PGD 0 
Dec  1 13:14:52 ph4 kernel: Oops: 0000 [#1] PREEMPT SMP 
Dec  1 13:14:52 ph4 kernel: Modules linked in: radeon fbcon bitblit fbcon_rotate fbcon_ccw fbcon_ud fbcon_cw softcursor font tileblit i2c_algo_bit drm_kms_helper snd_hda_codec_realtek ttm snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_intel snd_hda_controller snd_hda_codec snd_usb_audio drm ata_generic snd_usbmidi_lib snd_rawmidi snd_hwdep snd_seq_device pata_acpi snd_pcm snd_timer snd r8169 xhci_pci plusb usbnet xhci_hcd pata_jmicron soundcore pcspkr acpi_cpufreq k10temp mii asus_atk0110 i2c_piix4
Dec  1 13:14:52 ph4 kernel: CPU: 2 PID: 1283 Comm: mplayer Not tainted 3.18.0-rc4-gf487ce6 #1
Dec  1 13:14:52 ph4 kernel: Hardware name: System manufacturer System Product Name/M4A89GTD-PRO/USB3, BIOS 1456    05/04/2010
Dec  1 13:14:52 ph4 kernel: task: ffff880223a91830 ti: ffff880221dbc000 task.ti: ffff880221dbc000
Dec  1 13:14:52 ph4 kernel: RIP: 0010:[<ffffffffa0302044>]  [<ffffffffa0302044>] radeon_fence_signaled+0x44/0x90 [radeon]
Dec  1 13:14:52 ph4 kernel: RSP: 0018:ffff880221dbf968  EFLAGS: 00010246
Dec  1 13:14:52 ph4 kernel: RAX: 0000000000000000 RBX: ffff88022158c0c0 RCX: 000000018040002d
Dec  1 13:14:52 ph4 kernel: RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
Dec  1 13:14:52 ph4 kernel: RBP: ffff880221dbf988 R08: ffff880224479e80 R09: 0000000024479f01
Dec  1 13:14:52 ph4 kernel: R10: 000000000000bc00 R11: 0000000000000002 R12: 0000000000000000
Dec  1 13:14:52 ph4 kernel: R13: 0000000000000d40 R14: 0000000000000000 R15: ffff880221dbfbb0
Dec  1 13:14:52 ph4 kernel: FS:  00007f71123d3700(0000) GS:ffff88022fc80000(0000) knlGS:0000000000000000
Dec  1 13:14:52 ph4 kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
Dec  1 13:14:52 ph4 kernel: CR2: 0000000000000d48 CR3: 00000000c2fed000 CR4: 00000000000007e0
Dec  1 13:14:52 ph4 kernel: Stack:
Dec  1 13:14:52 ph4 kernel: ffff880221dbf988 ffff8800ced1f480 ffff8800ced1f680 ffff8800ce2b9a20
Dec  1 13:14:52 ph4 kernel: ffff880221dbf9b8 ffffffffa03750fc ffff880221dbf9b8 ffff8800ce2b9978
Dec  1 13:14:52 ph4 kernel: ffff880221dbfb38 ffff8800ce2b8000 ffff880221dbfac8 ffffffffa03756d8
Dec  1 13:14:52 ph4 kernel: Call Trace:
Dec  1 13:14:52 ph4 kernel: [<ffffffffa03750fc>] radeon_sa_bo_try_free+0x5c/0x70 [radeon]
Dec  1 13:14:52 ph4 kernel: [<ffffffffa03756d8>] radeon_sa_bo_new+0xf8/0x440 [radeon]
Dec  1 13:14:52 ph4 kernel: [<ffffffff812c87c7>] ? debug_smp_processor_id+0x17/0x20
Dec  1 13:14:52 ph4 kernel: [<ffffffffa03cd62d>] radeon_ib_get+0x3d/0xe0 [radeon]
Dec  1 13:14:52 ph4 kernel: [<ffffffffa031d732>] radeon_cs_ioctl+0x242/0x800 [radeon]
Dec  1 13:14:52 ph4 kernel: [<ffffffff810785b7>] ? dequeue_task_fair+0x9f7/0xaf0
Dec  1 13:14:52 ph4 kernel: [<ffffffffa01d91c1>] drm_ioctl+0x1a1/0x660 [drm]
Dec  1 13:14:52 ph4 kernel: [<ffffffff8106dd61>] ? get_parent_ip+0x11/0x50
Dec  1 13:14:52 ph4 kernel: [<ffffffff8106ddf5>] ? preempt_count_add+0x55/0xb0
Dec  1 13:14:52 ph4 kernel: [<ffffffff81548c03>] ? _raw_spin_unlock_irqrestore+0x13/0x40
Dec  1 13:14:52 ph4 kernel: [<ffffffffa02e6054>] radeon_drm_ioctl+0x54/0x90 [radeon]
Dec  1 13:14:52 ph4 kernel: [<ffffffff8117a920>] do_vfs_ioctl+0x2c0/0x4a0
Dec  1 13:14:52 ph4 kernel: [<ffffffff811848a4>] ? __fget+0x74/0xb0
Dec  1 13:14:52 ph4 kernel: [<ffffffff8117ab47>] SyS_ioctl+0x47/0x90
Dec  1 13:14:52 ph4 kernel: [<ffffffff81549796>] system_call_fastpath+0x16/0x1b
Dec  1 13:14:52 ph4 kernel: Code: 48 89 fb 4c 89 65 f0 8b 47 68 4c 8b 67 60 48 8b 7f 58 48 89 c2 48 89 c6 48 c1 e0 08 48 c1 e2 04 48 29 d0 4c 8d ac 07 40 0d 00 00 <49> 8b 45 08 49 39 c4 77 1b 48 89 df e8 4b 9b 08 e1 b8 01 00 00 
Dec  1 13:14:52 ph4 kernel: RIP  [<ffffffffa0302044>] radeon_fence_signaled+0x44/0x90 [radeon]
Dec  1 13:14:52 ph4 kernel: RSP <ffff880221dbf968>
Dec  1 13:14:52 ph4 kernel: CR2: 0000000000000d48
Dec  1 13:14:52 ph4 kernel: ---[ end trace 34d9f2e09283aa50 ]---