Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753280AbcCRXAf (ORCPT ); Fri, 18 Mar 2016 19:00:35 -0400 Received: from mail-io0-f173.google.com ([209.85.223.173]:36096 "EHLO mail-io0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751388AbcCRXA0 convert rfc822-to-8bit (ORCPT ); Fri, 18 Mar 2016 19:00:26 -0400 MIME-Version: 1.0 In-Reply-To: <20160318222625.GA1200@kroah.com> References: <20160318222625.GA1200@kroah.com> Date: Fri, 18 Mar 2016 17:00:25 -0600 X-Google-Profiles: ANGjdJ8l3-9Xl648YK5QIdQbmk4jNjL0KHNXakShVVVtpyReTPfEgcosG2t5TMtjqunjtFV4yMY6rfX0oLXfBEG1Jc2vUB-2-zv4TFjv3fVV7KdIXDiOKGbWXjhvFJs Message-ID: Subject: Re: USB Sound oops in Linus's latest tree From: Shuah Khan To: Greg KH Cc: Takashi Iwai , Jaroslav Kysela , Linus Torvalds , alsa-devel@alsa-project.org, linux-usb@vger.kernel.org, LKML , "Mauro Carvalho Chehab (Google+)" Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7782 Lines: 147 On Fri, Mar 18, 2016 at 4:26 PM, Greg KH wrote: > Hi, > > I'm getting the following oops with my USB sound device using Linus's > latest tree of the moment, which has the sound tree pull in it. Anyone > seen this before? > Hi Greg, Nicolai Stange sent in a fix for this problem - I can't find the link to this. It is coming in through Linux Media tree. thanks, -- Shuah The patch: With commit aebb2b89bff0 ("[media] sound/usb: Use Media Controller API to share media resources") an access to quirk->media_device without checking for quirk != NULL has been introduced in usb_audio_probe(). With a Plantronics USB headset (device ID 0x047f:0xc010) attached, this results in the following splat at boot time: BUG: unable to handle kernel NULL pointer dereference at 0000000000000014 IP: [] usb_audio_probe+0x2cc/0x9a0 [snd_usb_audio] Oops: 0000 [#1] SMP [...] CPU: 2 PID: 696 Comm: systemd-udevd Not tainted 4.5.0-next-20160315 #13 Hardware name: Dell Inc. Latitude E6540/0725FP, BIOS A10 06/26/2014 task: ffff88021c88d7c0 ti: ffff88003d5b0000 task.ti: ffff88003d5b0000 RIP: 0010:[] [] usb_audio_probe+0x2cc/0x9a0 [snd_usb_audio] [...] Call Trace: [] usb_probe_interface+0x136/0x2d0 [] driver_probe_device+0x22c/0x440 [] __driver_attach+0xd1/0xf0 [] ? driver_probe_device+0x440/0x440 [] bus_for_each_dev+0x6c/0xc0 [] driver_attach+0x1e/0x20 [] bus_add_driver+0x1c3/0x280 [] driver_register+0x60/0xe0 [] usb_register_driver+0x81/0x140 [] ? 0xffffffffa08c7000 [] usb_audio_driver_init+0x1e/0x1000 [snd_usb_audio] [] do_one_initcall+0xb3/0x1f0 [] ? __vunmap+0x81/0xd0 [] ? kmem_cache_alloc_trace+0x182/0x1d0 [] ? do_init_module+0x27/0x1d8 [] do_init_module+0x5f/0x1d8 [] load_module+0x1fe5/0x27a0 [] ? __symbol_put+0x60/0x60 [] ? vfs_read+0x110/0x130 [] SYSC_finit_module+0xe6/0x120 [] SyS_finit_module+0xe/0x10 [] do_syscall_64+0x64/0x110 [] entry_SYSCALL64_slow_path+0x25/0x25 After encountering this, the system-udevd process seems to be blocked until it is killed when hitting its timeout of 3min. In analogy to the other accesses to members of quirk in usb_audio_probe(), check for quirk != NULL before accessing its ->media_device. Fixes: aebb2b89bff0 ("[media] sound/usb: Use Media Controller API to share media resources") Signed-off-by: Nicolai Stange --- Applicable to linux-next-20160315. sound/usb/card.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sound/usb/card.c b/sound/usb/card.c index 63244bb..479621e 100644 --- a/sound/usb/card.c +++ b/sound/usb/card.c @@ -612,7 +612,7 @@ static int usb_audio_probe(struct usb_interface *intf, if (err < 0) goto __error; - if (quirk->media_device) { + if (quirk && quirk->media_device) { /* don't want to fail when media_snd_device_create() fails */ media_snd_device_create(chip, intf); } -- 2.7.2 > > [ +0.002298] input: Schiit Audio USB Modi Device as /devices/pci0000:00/0000:00:14.0/usb2/2-10/2-10.1/2-10.1:1.2/0003:0D8C:1319.0001/input/input17 > [ +0.000056] hid-generic 0003:0D8C:1319.0001: input,hidraw0: USB HID v1.00 Device [Schiit Audio USB Modi Device] on usb-0000:00:14.0-10.1/input2 > [ +0.008749] BUG: unable to handle kernel NULL pointer dereference at 0000000000000014 > [ +0.001151] IP: [] usb_audio_probe+0x1e1/0x8f0 [snd_usb_audio] > [ +0.001142] PGD 0 > [ +0.001114] Oops: 0000 [#1] PREEMPT SMP > [ +0.001115] Modules linked in: snd_usb_audio(+) hid_generic snd_usbmidi_lib usbhid snd_rawmidi snd_seq_device hid media arc4 fuse btusb btrtl btbcm btintel bluetooth rt2800usb rt2x00usb rt2800lib rt2x00lib mac80211 crc_ccitt cfg80211 rfkill nls_cp437 vfat fat iTCO_wdt iTCO_vendor_support mxm_wmi x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass crct10dif_pclmul crct10dif_common crc32_pclmul crc32c_intel ghash_clmulni_intel aesni_intel aes_x86_64 glue_helper lrw gf128mul ablk_helper cryptd psmouse serio_raw pcspkr firewire_ohci firewire_core crc_itu_t xhci_pci ehci_pci xhci_hcd ehci_hcd mei_me usbcore mei lpc_ich mfd_core usb_common wmi evdev ip_tables x_tables > [ +0.004079] CPU: 4 PID: 615 Comm: systemd-udevd Not tainted 4.6.0-rc1+ #103 > [ +0.001382] Hardware name: / , BIOS KLZ8711D.86A.0457.2015.0713.1319 07/13/2015 > [ +0.001387] task: ffff880098ec0e00 ti: ffff880251920000 task.ti: ffff880251920000 > [ +0.001417] RIP: 0010:[] [] usb_audio_probe+0x1e1/0x8f0 [snd_usb_audio] > [ +0.001414] RSP: 0018:ffff880251923af0 EFLAGS: 00010246 > [ +0.001409] RAX: 0000000000000000 RBX: ffff88024d602000 RCX: 0000000000000000 > [ +0.001404] RDX: ffff880254e0b340 RSI: ffff8802559b99f8 RDI: ffffffff82181030 > [ +0.001413] RBP: ffff880251923b50 R08: 0000000000019d00 R09: ffffffff81385837 > [ +0.001431] R10: ffffea0009461200 R11: ffff880253b3fe72 R12: 0000000000000000 > [ +0.001411] R13: 0000000000000000 R14: 0000000000000001 R15: ffff88025338c212 > [ +0.001436] FS: 00007f7a8db567c0(0000) GS:ffff88025fb00000(0000) knlGS:0000000000000000 > [ +0.001431] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ +0.001445] CR2: 0000000000000014 CR3: 0000000251854000 CR4: 00000000001406e0 > [ +0.001451] Stack: > [ +0.001433] ffff880253302e88 ffff88024d602054 ffff88009879d000 ffff880253302e88 > [ +0.001480] ffff880255f7e000 386430425355d030 ff00393133313a63 ffff8800984f4098 > [ +0.001466] ffff8800984f4000 ffffffffc0e95728 ffff88009879d030 ffffffffc0e955a0 > [ +0.001497] Call Trace: > [ +0.001295] [] usb_probe_interface+0x1bd/0x300 [usbcore] > [ +0.001427] [] driver_probe_device+0x249/0x450 > [ +0.001400] [] __driver_attach+0x84/0x90 > [ +0.001398] [] ? driver_probe_device+0x450/0x450 > [ +0.001417] [] bus_for_each_dev+0x64/0xa0 > [ +0.001369] [] driver_attach+0x1e/0x20 > [ +0.001396] [] bus_add_driver+0x1eb/0x280 > [ +0.001365] [] driver_register+0x60/0xe0 > [ +0.001369] [] usb_register_driver+0x84/0x140 [usbcore] > [ +0.001422] [] ? 0xffffffffc0e9d000 > [ +0.001370] [] usb_audio_driver_init+0x1e/0x20 [snd_usb_audio] > [ +0.001472] [] do_one_initcall+0xab/0x1d0 > [ +0.001547] [] do_init_module+0x5f/0x1cd > [ +0.001469] [] load_module+0x1368/0x1510 > [ +0.001542] [] ? symbol_put_addr+0x50/0x50 > [ +0.001468] [] SyS_finit_module+0xc8/0xf0 > [ +0.001451] [] do_syscall_64+0x5e/0xc0 > [ +0.001538] [] entry_SYSCALL64_slow_path+0x25/0x25 > [ +0.001397] Code: f8 01 00 44 89 e6 48 89 df e8 dc 73 00 00 85 c0 89 c1 0f 88 99 00 00 00 48 8b 7b 10 e8 c9 0b 80 c0 85 c0 89 c1 0f 88 86 00 00 00 <41> 80 7d 14 00 0f 85 90 04 00 00 48 63 03 48 89 1c c5 40 90 e9 > [ +0.001513] RIP [] usb_audio_probe+0x1e1/0x8f0 [snd_usb_audio] > [ +0.001468] RSP > [ +0.001576] CR2: 0000000000000014 > [ +0.010610] ---[ end trace c9cdd61401b8f1d9 ]---