Comment 3 for bug 1624541

My system seems to works on kernel 'Linux ubuntu-Inspiron-5447 4.4.0-49-generic #70-Ubuntu SMP Fri Nov 11 16:40:34 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux'

but I've noted some crashs with this info:

Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.860595] BUG: unable to handle kernel NULL pointer dereference at 0000000000000248
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.860634] IP: [<ffffffffc0130f82>] amdgpu_vm_grab_id+0x122/0x310 [amdgpu]
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.860688] PGD 0
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.860698] Oops: 0000 [#1] SMP
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.860714] Modules linked in: rfcomm vmw_vsock_vmci_transport vsock vmw_vmci bnep drbg ansi_cprng ctr ccm rtsx_usb_ms memstick rtsx_usb_sdmmc rtsx_usb zram binfmt_misc nls_iso8859_1 joydev hid_generic hid_multitouch hid_rmi dell_wmi sparse_keymap dell_laptop dcdbas dell_smm_hwmon intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 uvcvideo lrw gf128mul arc4 glue_helper ablk_helper videobuf2_vmalloc cryptd videobuf2_memops psmouse videobuf2_v4l2 dell_led radio_keene input_leds videobuf2_core serio_raw ath9k v4l2_common ath9k_common videodev ath9k_hw media snd_hda_codec_hdmi snd_hda_codec_realtek snd_usb_audio snd_hda_codec_generic ath snd_usbmidi_lib mac80211 snd_hda_intel snd_hda_codec ath3k btusb snd_hda_core btrtl btbcm snd_hwdep btintel bluetooth cfg80211 snd_seq_midi usbhid snd_seq_midi_event snd_soc_rt5640 snd_rawmidi snd_soc_rl6231 r8169 snd_soc_core mii snd_seq snd_compress ac97_bus snd_seq_device snd_pcm_dmaengine snd_pcm elan_i2c snd_timer i2c_hid hid mei_me lpc_ich mei snd shpchp soundcore dell_rbtn dw_dmac dw_dmac_core 8250_dw sdhci_acpi fjes soc_button_array i2c_designware_platform spi_pxa2xx_platform sdhci i2c_designware_core mac_hid kvm_intel kvm irqbypass lz4 lz4_compress parport_pc ppdev lp parport autofs4 btrfs xor raid6_pq amdkfd amd_iommu_v2 i915 amdgpu ttm i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm ahci libahci wmi video
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.861362] CPU: 3 PID: 167 Comm: gfx Not tainted 4.4.0-49-generic #70-Ubuntu
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.861390] Hardware name: Dell Inc. Inspiron 5447/0K5C1C, BIOS A05 08/12/2014
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.861417] task: ffff880449773700 ti: ffff880036b14000 task.ti: ffff880036b14000
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.861445] RIP: 0010:[<ffffffffc0130f82>] [<ffffffffc0130f82>] amdgpu_vm_grab_id+0x122/0x310 [amdgpu]
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.861496] RSP: 0018:ffff880036b17ce0 EFLAGS: 00010246
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.861517] RAX: 0000000000000000 RBX: ffff880448a20000 RCX: ffff8803fa8e6c00
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.861543] RDX: 000003e8000003e8 RSI: ffff880448a22dc0 RDI: ffff88003653be40
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.861569] RBP: ffff880036b17db0 R08: ffff8803fa8e6c00 R09: 0000000000000000
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.861595] R10: ffff880036b17b58 R11: 0000000000002f93 R12: ffff880448a22dc0
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.861621] R13: ffff88003653be40 R14: ffff880448a20838 R15: 0000000000000001
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.861647] FS: 0000000000000000(0000) GS:ffff88045f2c0000(0000) knlGS:0000000000000000
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.861677] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.861698] CR2: 0000000000000248 CR3: 0000000002e0a000 CR4: 00000000001406e0
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.863009] Stack:
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.864270] ffff88041de9e648 0000000000000000 ffff8803fa8e6c00 0000000000000000
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.865548] 0000000000000000 0000000000000000 0000000000000000 0000000000000000
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.866825] 0000000000000000 0000000000000000 0000000000000000 0000000000000000
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.868078] Call Trace:
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.869317] [<ffffffffc0132dc0>] amdgpu_ib_schedule+0x90/0x390 [amdgpu]
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.870573] [<ffffffffc016f5a6>] amdgpu_sched_run_job+0x36/0x140 [amdgpu]
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.871820] [<ffffffffc016edbf>] amd_sched_main+0x23f/0x400 [amdgpu]
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.873046] [<ffffffff810c3ec0>] ? wake_atomic_t_function+0x60/0x60
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.874278] [<ffffffffc016eb80>] ? amd_sched_entity_wakeup+0x70/0x70 [amdgpu]
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.875482] [<ffffffff810a09d8>] kthread+0xd8/0xf0
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.876677] [<ffffffff810a0900>] ? kthread_create_on_node+0x1e0/0x1e0
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.877870] [<ffffffff818363cf>] ret_from_fork+0x3f/0x70
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.879039] [<ffffffff810a0900>] ? kthread_create_on_node+0x1e0/0x1e0
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.880195] Code: c0 44 89 bc 85 48 ff ff ff 41 83 c7 01 44 39 bb 1c 09 00 00 76 4f 49 83 c6 10 4d 8b 6e f0 4d 85 ed 74 66 4c 89 ef e8 ce 2e ff ff <8b> b8 48 02 00 00 48 8b b4 fd 50 ff ff ff 48 85 f6 74 b2 41 8b
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.882721] RIP [<ffffffffc0130f82>] amdgpu_vm_grab_id+0x122/0x310 [amdgpu]
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.883974] RSP <ffff880036b17ce0>
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.885193] CR2: 0000000000000248
Nov 27 05:35:35 ubuntu-Inspiron-5447 kernel: [ 303.891186] ---[ end trace 6f73582cbf32c937 ]---