RHEL7.3 kernel OOPS: mixAudioStreamSamplesIntoOutputBuffer

Hi,

Getting this panic in our production servers every other day or so. Even though this OOPS/bug is coming, the audio seems working ok. This was with 10.8-a2 and we know this is a bit old but before upgrading without knowing if a newer version will help, just wanted to dump the dmesg-output and see if someone can answer.

We've read the release notes for the latest version (10.8.4) but it's not on this low level so it's impossible to know if the below has been/is a known issue or not.

The kernel we use is: 3.10.0-514.el7.x86_64

Thanks!
/Tomas

Code: Select all

[13267.110713] BUG: unable to handle kernel paging request at ffffc90001d16000
[13267.110750] IP: [<ffffffffa069317b>] _Z28mixAudioSamples_16bit_scalarPPvPiiij+0x8b/0x100 [blackmagic]
[13267.110803] PGD 187c58067 PUD 307c03067 PMD 275a0c067 PTE ffe7811d5b661027
[13267.110826] Oops: 0009 [#1] SMP
[13267.110840] Modules linked in: intel_powerclamp coretemp intel_rapl iosf_mbi kvm_intel kvm irqbypass crc32_pclmul ghash_clmulni_intel aesni_intel lrw gf128mul glue_helper ablk_helper cryptd snd_hda_codec_hdmi ipmi_ssif ipmi_devintf iTCO_wdt iTCO_vendor_support snd_hda_intel pcspkr snd_hda_codec blackmagic(POE) snd_hda_core snd_hwdep snd_seq sb_edac snd_seq_device edac_core snd_pcm i2c_i801 sg lpc_ich hpilo hpwdt snd_timer snd soundcore ioatdma shpchp dca ipmi_si ipmi_msghandler pcc_cpufreq acpi_power_meter nfsd nfs_acl lockd grace auth_rpcgss sunrpc ip_tables xfs libcrc32c sd_mod crc_t10dif crct10dif_generic nouveau video mgag200 mxm_wmi i2c_algo_bit crct10dif_pclmul crct10dif_common drm_kms_helper crc32c_intel serio_raw syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm tg3 hpsa ptp i2c_core
[13267.111085]  scsi_transport_sas pps_core wmi fjes dm_mirror dm_region_hash dm_log dm_mod
[13267.111109] CPU: 7 PID: 1923 Comm: kontrib Tainted: P           OE  ------------   3.10.0-514.el7.x86_64 #1
[13267.111136] Hardware name: HP ProLiant DL360 Gen9, BIOS P89 07/20/2015
[13267.111154] task: ffff880074560fb0 ti: ffff88026bb14000 task.ti: ffff88026bb14000
[13267.111174] RIP: 0010:[<ffffffffa069317b>]  [<ffffffffa069317b>] _Z28mixAudioSamples_16bit_scalarPPvPiiij+0x8b/0x100 [blackmagic]
[13267.111218] RSP: 0018:ffff88026bb17c00  EFLAGS: 00010002
[13267.111234] RAX: 0000000000000001 RBX: ffffc9000634f000 RCX: 0000000000000000
[13267.111253] RDX: ffffc9000634f000 RSI: ffffc90001d16000 RDI: 0000000000000002
[13267.111272] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
[13267.111291] R10: 0000000000000000 R11: ffffc9000634f004 R12: 0000000000000004
[13267.111310] R13: 0000000000000400 R14: ffffc90001d16000 R15: ffff88026bb17c40
[13267.111329] FS:  00007fc2bffff700(0000) GS:ffff88047fcc0000(0000) knlGS:0000000000000000
[13267.111351] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[13267.111367] CR2: ffffc90001d16000 CR3: 000000026a715000 CR4: 00000000001407e0
[13267.111386] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[13267.111405] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[13267.111424] Stack:
[13267.111432]  0000000000000000 00000000000097c0 ffff880476d86d80 ffff880272548088
[13267.111455]  ffff88026bb17c40 ffff880463707160 ffffffffa0694dbe 0000000000000000
[13267.111480]  ffffc90001d16000 0000000000000202 0000000000000206 ffff880272548088
[13267.111502] Call Trace:
[13267.111525]  [<ffffffffa0694dbe>] ? _ZN23AudioOutputSupportClass37mixAudioStreamSamplesIntoOutputBufferEP27BlackmagicAudioOutputStreamPvxj+0x1ee/0x210 [blackmagic]
[13267.111571]  [<ffffffffa0695437>] ? _ZN23AudioOutputSupportClass29writeAudioOutputStreamSamplesEP27BlackmagicAudioOutputStreamPvS2_jjPjx+0x3e7/0x460 [blackmagic]
[13267.111615]  [<ffffffffa069ba67>] ? _ZN15UserClientClass23audioOutputWriteSamplesEP32BlackmagicAudioOutputWriteParamsPjjS2_+0x87/0x150 [blackmagic]
[13267.111653]  [<ffffffffa064dff6>] ? blackmagic_ioctl_private+0x1fa6/0x4080 [blackmagic]
[13267.111679]  [<ffffffff810f4c18>] ? get_futex_key+0x1c8/0x2c0
[13267.111697]  [<ffffffff810f4f30>] ? futex_wake+0x80/0x160
[13267.111720]  [<ffffffffa06a1019>] ? blackmagic_ioctl+0x49/0x70 [blackmagic]
[13267.111743]  [<ffffffff81211ed5>] ? do_vfs_ioctl+0x2d5/0x4b0
[13267.111759]  [<ffffffff81212151>] ? SyS_ioctl+0xa1/0xc0
[13267.112518]  [<ffffffff816964c9>] ? system_call_fastpath+0x16/0x1b
[13267.113276] Code: 81 f9 00 00 80 ff 7f 4d 41 c7 03 00 00 80 ff 49 83 c2 02 49 83 c3 08 48 83 c2 08 44 39 d7 7e 4a 44 89 d1 8d 41 01 44 39 c0 74 0d <46> 0f bf 0c 56 41 c1 e1 08 45 03 4b fc 41 81 f9 00 00 80 ff 7e
[13267.114847] RIP  [<ffffffffa069317b>] _Z28mixAudioSamples_16bit_scalarPPvPiiij+0x8b/0x100 [blackmagic]
[13267.115627]  RSP <ffff88026bb17c00>
[13267.116382] CR2: ffffc90001d16000
[root@stb-lc-decoder-01 127.0.0.1-2017-01-18-08:03:27]# uname -a
Linux stb-lc-decoder-01.nix.cydmodule.com 3.10.0-514.el7.x86_64 #1 SMP Wed Oct 19 11:24:13 EDT 2016 x86_64 x86_64 x86_64 GNU/Linux


[Nicholas Gill]

Hi Thomas,

If the system exhibiting this issue uses an Intel CPU with the SMAP[1] feature (Broadwell / Skylake architecture), I recommend testing with Desktop Video 10.8.1+ as a correction was added for an issue with a similar backtrace to that shown in your post.

If you are developing an application using the DeckLink API, I also recommend confirming that the timestamps used to schedule audio are calculated as BMDTimeValue (64bit) values, as a similar issue has been observed after 24hrs of playback (2^32 / 48000 seconds, ~24.8hrs) when 32bit values are used by the application for audio stream time (with a timescale of 48000), when the 32bit value overflows.

A ticket exists to improve the DeckLink driver behaviour if the application stream time wraps, however if this is the case the application must be modified to correctly calculate the audio playback stream time to avoid the audio samples with incorrect stream time being dropped.

Hope that helps,

-nick

[1] Supervisor Mode Access Prevention