OOPS in latest mainline tree null pointer dereference in usb audio probe

From: Jon Christopherson
Date: Tue Mar 22 2016 - 16:20:17 EST

Hello All,

The latest mainline code from ~1 hour ago is giving me a oops in the usb audio path:

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[ 14.985811] BUG: unable to handle kernel NULL pointer dereference at 0000000000000014
[ 14.985814] IP: [<ffffffffc16cda2c>] usb_audio_probe+0x2cc/0x9a0 [snd_usb_audio]
[ 14.985821] PGD 83d6e3067 PUD 83d6e4067 PMD 0
[ 14.985823] Oops: 0000 [#1] SMP
[ 14.985824] Modules linked in: nvidia_uvm(POE) nvidia_modeset(POE) mxm_wmi intel_rapl x86_pkg_temp_thermal intel_powerclamp snd_hda_codec_realtek(+) kvm_intel snd_hda_codec_generic kvm i915 irqbypass uvcvideo(+) hid_logitech_hidpp joydev videobuf2_vmalloc serio_raw videobuf2_memops drm_kms_helper videobuf2_v4l2 snd_usb_audio(+) i2c_algo_bit videobuf2_core fb_sys_fops snd_usbmidi_lib syscopyarea videodev sysfillrect dm_multipath sysimgblt media snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_pcm snd_seq_midi snd_seq_midi_event wl(POE) snd_rawmidi btusb btrtl snd_seq cfg80211 snd_seq_device snd_timer snd nvidia(POE) soundcore drm mei_me mei hci_uart btbcm parport_pc btintel bluetooth wmi pinctrl_sunrisepoint ppdev pinctrl_intel i2c_hid msr mac_hid acpi_pad coretemp lp parport nls_iso8859_1 btrfs xor raid6_pq dm_mirror dm_region_hash dm_log dm_crypt hid_logitech_dj hid_generic usbhid hid crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd nvme psmouse nvme_core ahci libahci video
[ 14.985848] CPU: 4 PID: 867 Comm: systemd-udevd Tainted: P OE 4.6.0-168-generic #201603221445
[ 14.985849] Hardware name: System manufacturer System Product Name/Z170-DELUXE, BIOS 1702 01/28/2016
[ 14.985850] task: ffff88083d699e80 ti: ffff88083d6f4000 task.ti: ffff88083d6f4000
[ 14.985851] RIP: 0010:[<ffffffffc16cda2c>] [<ffffffffc16cda2c>] usb_audio_probe+0x2cc/0x9a0 [snd_usb_audio]
[ 14.985855] RSP: 0018:ffff88083d6f7aa8 EFLAGS: 00010246
[ 14.985856] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[ 14.985857] RDX: ffff88083b630700 RSI: 0000000000000000 RDI: ffff88083e35f580
[ 14.985857] RBP: ffff88083d6f7b20 R08: 000000000001a280 R09: ffffffff813cb367
[ 14.985858] R10: ffffea0020f8d400 R11: 0000000000000000 R12: ffff88083bd4dc00
[ 14.985859] R13: 0000000000000001 R14: ffff88083bd4dc54 R15: ffff88083a925932
[ 14.985860] FS: 00007f1bfd71c880(0000) GS:ffff880866500000(0000) knlGS:0000000000000000
[ 14.985860] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 14.985861] CR2: 0000000000000014 CR3: 000000083d6e1000 CR4: 00000000003406e0
[ 14.985862] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 14.985863] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 14.985863] Stack:
[ 14.985864] ffff88083b0db348 0000000000000000 ffff88083af79c00 ffff88083b0db348
[ 14.985865] 0000000200000246 0000000000000246 ffff88083a9df000 363430425355f836
[ 14.985866] 0000333438303a64 00000000bda88ff6 ffff88083c377898 ffff88083c377800
[ 14.985868] Call Trace:
[ 14.985871] [<ffffffff815e76dd>] usb_probe_interface+0x1bd/0x300
[ 14.985873] [<ffffffff81523c3c>] driver_probe_device+0x22c/0x440
[ 14.985875] [<ffffffff81523f21>] __driver_attach+0xd1/0xf0
[ 14.985876] [<ffffffff81523e50>] ? driver_probe_device+0x440/0x440
[ 14.985877] [<ffffffff81521854>] bus_for_each_dev+0x64/0xa0
[ 14.985879] [<ffffffff8152334e>] driver_attach+0x1e/0x20
[ 14.985880] [<ffffffff81522e1b>] bus_add_driver+0x1eb/0x280
[ 14.985881] [<ffffffff81524850>] driver_register+0x60/0xe0
[ 14.985883] [<ffffffff815e6054>] usb_register_driver+0x84/0x140
[ 14.985884] [<ffffffffc16fa000>] ? 0xffffffffc16fa000
[ 14.985889] [<ffffffffc16fa01e>] usb_audio_driver_init+0x1e/0x1000 [snd_usb_audio]
[ 14.985890] [<ffffffff81002123>] do_one_initcall+0xb3/0x200
[ 14.985892] [<ffffffff811e7906>] ? kmem_cache_alloc_trace+0x176/0x1e0
[ 14.985894] [<ffffffff81184a18>] do_init_module+0x5f/0x1df
[ 14.985896] [<ffffffff81103d90>] load_module+0x16c0/0x1c60
[ 14.985897] [<ffffffff81100560>] ? __symbol_put+0x40/0x40
[ 14.985899] [<ffffffff81104563>] SYSC_finit_module+0xc3/0xf0
[ 14.985900] [<ffffffff811045ae>] SyS_finit_module+0xe/0x10
[ 14.985902] [<ffffffff81803376>] entry_SYSCALL_64_fastpath+0x1e/0xa8
[ 14.985903] Code: 02 00 8b 75 ac 4c 89 e7 e8 72 74 00 00 85 c0 89 c1 0f 88 ae 00 00 00 49 8b 7c 24 10 e8 be 8e c4 fe 85 c0 89 c1 0f 88 9a 00 00 00 <80> 7b 14 00 0f 85 4c 04 00 00 49 63 04 24 4c 89 24 c5 c0 ea 6e
[ 14.985917] RIP [<ffffffffc16cda2c>] usb_audio_probe+0x2cc/0x9a0 [snd_usb_audio]
[ 14.985921] RSP <ffff88083d6f7aa8>
[ 14.985922] CR2: 0000000000000014
[ 14.985923] ---[ end trace f2b3492837fdc127 ]---
====

Last known good build without this oops was Mar 16 19:15.


--

Regards,

Jon Christopherson
jon@xxxxxxxx