I have been running the original code (because of issues with the patch) for a while with some added printks. This morning I found this NULL pointer derefence: [47772.121968] DEBUG: vb2_thread_stop entered [47772.122014] BUG: unable to handle kernel NULL pointer dereference at (null) [47772.122042] vb2: counters for queue ffff880407ee9828: UNBALANCED! [47772.122043] vb2: setup: 1 start_streaming: 1 stop_streaming: 1 [47772.122043] vb2: wait_prepare: 249333 wait_finish: 249334 [47772.122083] IP: [<ffffffffa057b65c>] cx23885_buf_prepare+0x6c/0xd0 [cx23885] [47772.122102] PGD 0 [47772.122107] Oops: 0000 [#1] SMP [47772.122116] Modules linked in: cfg80211 rfkill nf_conntrack_netbios_ns nf_conntrack_broadcast ip6t_rpfilter ip6t_REJECT xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw sp2(OE) si2157(OE) si2168(OE) i2c_mux cx25840(OE) cx23885(OE) altera_ci(OE) tda18271(OE) altera_stapl(OE) videobuf2_dvb(OE) videobuf2_core(OE) videobuf2_dma_sg(OE) videobuf2_memops(OE) snd_seq snd_seq_device snd_pcm snd_timer snd soundcore tveeprom(OE) cx2341x(OE) dvb_core(OE) rc_core(OE) v4l2_common(OE) videodev(OE) raid456 async_raid6_recov async_memcpy [47772.122321] async_pq async_xor xor async_tx raid6_pq media(OE) mxm_wmi intel_rapl x86_pkg_temp_thermal coretemp kvm_intel kvm serio_raw shpchp mei_me mei i2c_i801 crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel microcode dw_dmac wmi dw_dmac_core tpm_tis tpm i2c_hid i2c_designware_platform i2c_designware_core acpi_pad nfsd auth_rpcgss nfs_acl lockd sunrpc e1000e i915 ptp pps_core i2c_algo_bit drm_kms_helper drm sdhci_acpi sdhci mmc_core video [47772.122472] CPU: 0 PID: 6151 Comm: vb2-cx23885[2] Tainted: G OE 3.17.8-200.fc20.x86_64 #1 [47772.122492] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./Z97 Extreme4, BIOS P1.50 12/17/2014 [47772.122523] task: ffff8803dcfc9d70 ti: ffff8803652a8000 task.ti: ffff8803652a8000 [47772.122549] RIP: 0010:[<ffffffffa057b65c>] [<ffffffffa057b65c>] cx23885_buf_prepare+0x6c/0xd0 [cx23885] [47772.122573] RSP: 0018:ffff8803652abdc8 EFLAGS: 00010246 [47772.122585] RAX: 0000000000005e00 RBX: ffff880036a6d600 RCX: 00000000000002f0 [47772.122609] RDX: 0000000000005e00 RSI: ffff88040608a3b8 RDI: ffff8804091f3000 [47772.122624] RBP: ffff8803652abdf0 R08: 0000000000000020 R09: 0000000000000000 [47772.122649] R10: ffff880407ee9828 R11: ffff880407ee9828 R12: ffff88040608a000 [47772.122663] R13: 0000000000005e00 R14: ffff880036a6c000 R15: 0000000000000000 [47772.122677] FS: 0000000000000000(0000) GS:ffff88041fa00000(0000) knlGS:0000000000000000 [47772.122693] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [47772.122705] CR2: 0000000000000000 CR3: 0000000001c14000 CR4: 00000000001407f0 [47772.122720] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [47772.123643] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [47772.124605] Stack: [47772.125468] ffff88040608a000 ffff88040608c458 ffff88040608a000 0000000000000000 [47772.126350] ffff880407ee9828 ffff8803652abe00 ffffffffa057cd69 ffff8803652abe30 [47772.127230] ffffffffa04f183e 0000000000005e00 ffff880407ee9828 ffff88040608c458 [47772.128129] Call Trace: [47772.129002] [<ffffffffa057cd69>] buffer_prepare+0x19/0x20 [cx23885] [47772.129916] [<ffffffffa04f183e>] __buf_prepare+0x27e/0x390 [videobuf2_core] [47772.130838] [<ffffffffa04f301b>] vb2_internal_qbuf+0x6b/0x210 [videobuf2_core] [47772.131722] [<ffffffffa04f32f6>] vb2_thread+0x136/0x4d0 [videobuf2_core] [47772.132642] [<ffffffffa04f31c0>] ? vb2_internal_qbuf+0x210/0x210 [videobuf2_core] [47772.133527] [<ffffffff810b04b8>] kthread+0xd8/0xf0 [47772.134400] [<ffffffff810b03e0>] ? kthread_create_on_node +0x190/0x190 [47772.135268] [<ffffffff8173057c>] ret_from_fork+0x7c/0xb0 [47772.136134] [<ffffffff810b03e0>] ? kthread_create_on_node +0x190/0x190 [47772.137058] Code: 24 60 02 00 00 85 c0 75 3e 45 85 ed 75 4d 90 8b 8b f0 00 00 00 49 8b be 20 01 00 00 49 8d b4 24 b8 03 00 00 44 8b 83 f4 00 00 00 <49> 8b 17 45 31 c9 e8 c9 f0 ff ff 31 c0 5b 41 5c 41 5d 41 5e 41 [47772.138917] RIP [<ffffffffa057b65c>] cx23885_buf_prepare+0x6c/0xd0 [cx23885] [47772.139841] RSP <ffff8803652abdc8> [47772.140776] CR2: 0000000000000000 [47772.146080] ---[ end trace 2c986045fea9fe0a ]--- [47772.146236] DEBUG: vb2_thread_stop quit This happened only once normally it just prints: [47179.170117] DEBUG: vb2_thread [47400.670021] DEBUG: vb2_thread_stop entered [47400.670105] DEBUG: vb2_thread_stop quit [47401.012711] DEBUG: vb2_thread [47456.200792] DEBUG: vb2_thread_stop entered [47456.200908] DEBUG: vb2_thread_stop quit [47456.544154] DEBUG: vb2_thread [47480.938606] DEBUG: vb2_thread_stop entered [47480.938711] DEBUG: vb2_thread_stop quit [47481.024019] DEBUG: vb2_thread [47708.823051] DEBUG: vb2_thread_stop entered [47708.823184] DEBUG: vb2_thread_stop quit [47709.166499] DEBUG: vb2_thread Regards, Jurgen -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
