Hey Srinivas, I noticed a kernel panic when the hid-sensor-hub is removed and a trigger/buffer has been setup. My device changes it's HID ID depending on which microsoft keyboard is attached. This change removes the USB device and reattaches it. I belive the kernel panic happens since it's trying to send a usb packet after the device is gone. The usb packet is created by hid_sensor_power_state() when the trigger predisabled callback is called. I have a fix that checks hid_device->status before calling hid_sensor_power_state() but I had to set hid_device->status, to removed, earlier in hid-core hid_destroy_device() for this to work. I'll post the kernel panic below. Do you think using hid_device status is appropriate or should some other variable be used, maybe one per hid sensor hub device? [ 234.449988] BUG: unable to handle kernel NULL pointer dereference at 0000000000000058 [ 234.450134] IP: [<ffffffff8161746f>] hid_submit_ctrl+0x7f/0x290 [ 234.450234] PGD 0 [ 234.450275] Oops: 0002 [#1] PREEMPT SMP [ 234.450348] Modules linked in: uinput ip6t_rpfilter ip6t_REJECT fuse 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 mwifiex_usb mwifiex cfg80211 x86_pkg_temp_thermal rfkill coretemp kvm_intel hid_sensor_rotation hid_sensor_als hid_sensor_accel_3d hid_sensor_gyro_3d hid_sensor_magn_3d(O) hid_sensor_incl_3d hid_sensor_trigger kvm hid_sensor_iio_common industrialio_triggered_buffer snd_hda_codec_realtek kfifo_buf snd_hda_codec_generic snd_hda_codec_hdmi industrialio snd_hda_intel iTCO_wdt iTCO_vendor_support snd_hda_controller [ 234.451613] snd_hda_codec vfat fat crc32_pclmul snd_hwdep crc32c_intel uvcvideo snd_seq ghash_clmulni_intel videobuf2_vmalloc videobuf2_memops microcode videobuf2_core v4l2_common snd_seq_device videodev joydev snd_pcm hid_sensor_hub media snd_timer snd hid_multitouch i2c_i801 mei_me lpc_ich mei tpm_infineon soundcore tpm_tis tpm i2c_hid i2c_designware_platform i2c_designware_core binfmt_misc i915 i2c_algo_bit drm_kms_helper drm sd_mod i2c_core video [ 234.452205] CPU: 2 PID: 39 Comm: khubd Tainted: G IO 3.16.0-rc5+ #112 [ 234.452284] Hardware name: Microsoft Corporation Surface Pro 2/Surface Pro 2, BIOS 2.03.0250 09/06/2013 [ 234.452383] task: ffff880118aba6e0 ti: ffff8800daf80000 task.ti: ffff8800daf80000 [ 234.452461] RIP: 0010:[<ffffffff8161746f>] [<ffffffff8161746f>] hid_submit_ctrl+0x7f/0x290 [ 234.452558] RSP: 0018:ffff8800daf83750 EFLAGS: 00010086 [ 234.452616] RAX: 0000000080000300 RBX: ffff88003f60c000 RCX: 0000000000000000 [ 234.452690] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff880117f78000 [ 234.452767] RBP: ffff8800daf83788 R08: 0000000000000001 R09: 0000000000000001 [ 234.452842] R10: 0000000000000001 R11: 0000000000000000 R12: ffff880117f78000 [ 234.452919] R13: ffff88003f11a290 R14: 000000000000000c R15: ffff880091cb3ab8 [ 234.452993] FS: 0000000000000000(0000) GS:ffff88011b000000(0000) knlGS:0000000000000000 [ 234.453077] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 234.453139] CR2: 0000000000000058 CR3: 0000000001c11000 CR4: 00000000001407e0 [ 234.453216] Stack: [ 234.453241] ffff880117f3dcd0 ffff880117f78000 ffff88003f60c000 ffff880117f78000 [ 234.453335] ffff880117f78000 ffff88003f11a290 0000000000000000 ffff8800daf837b0 [ 234.453431] ffffffff81617707 ffff880117f78000 ffff88003f60c000 0000000000000013 [ 234.453527] Call Trace: [ 234.453565] [<ffffffff81617707>] usbhid_restart_ctrl_queue+0x87/0x140 [ 234.453641] [<ffffffff81617a88>] usbhid_submit_report+0x2c8/0x370 [ 234.453711] [<ffffffff81617b4a>] usbhid_request+0x1a/0x30 [ 234.453783] [<ffffffffa020edfb>] sensor_hub_set_feature+0x8b/0xd0 [hid_sensor_hub] [ 234.453867] [<ffffffffa02d9084>] hid_sensor_power_state+0x84/0x110 [hid_sensor_trigger] [ 234.453920] [<ffffffffa02d9129>] hid_sensor_data_rdy_trigger_set_state+0x19/0x20 [hid_sensor_trigger] [ 234.453981] [<ffffffffa034d5b7>] iio_triggered_buffer_predisable+0xa7/0xb0 [industrialio] [ 234.454035] [<ffffffffa034cc4a>] iio_disable_all_buffers+0x3a/0xc0 [industrialio] [ 234.454084] [<ffffffffa03487d3>] iio_device_unregister+0x53/0x80 [industrialio] [ 234.454130] [<ffffffffa026c06a>] hid_accel_3d_remove+0x2a/0x50 [hid_sensor_accel_3d] [ 234.454179] [<ffffffff814f433d>] platform_drv_remove+0x1d/0x40 [ 234.454217] [<ffffffff814f18bf>] __device_release_driver+0x7f/0xf0 [ 234.454255] [<ffffffff814f1955>] device_release_driver+0x25/0x40 [ 234.454293] [<ffffffff814f121c>] bus_remove_device+0x11c/0x1a0 [ 234.454329] [<ffffffff814ed7d6>] device_del+0x136/0x1e0 [ 234.454369] [<ffffffff81512190>] ? mfd_cell_disable+0x80/0x80 [ 234.454406] [<ffffffff814f41d1>] platform_device_del+0x21/0xc0 [ 234.454443] [<ffffffff814f4282>] platform_device_unregister+0x12/0x30 [ 234.454482] [<ffffffff815121d3>] mfd_remove_devices_fn+0x43/0x50 [ 234.454518] [<ffffffff814ed3e3>] device_for_each_child+0x43/0x70 [ 234.454555] [<ffffffff81512105>] mfd_remove_devices+0x25/0x30 [ 234.454595] [<ffffffffa020ebd7>] sensor_hub_remove+0x87/0x140 [hid_sensor_hub] [ 234.454639] [<ffffffff81607c5b>] hid_device_remove+0x6b/0xd0 [ 234.454677] [<ffffffff814f18bf>] __device_release_driver+0x7f/0xf0 [ 234.454734] [<ffffffff814f1955>] device_release_driver+0x25/0x40 [ 234.454765] [<ffffffff814f121c>] bus_remove_device+0x11c/0x1a0 [ 234.454795] [<ffffffff814ed7d6>] device_del+0x136/0x1e0 [ 234.454822] [<ffffffff81607d47>] hid_destroy_device+0x27/0x60 [ 234.454852] [<ffffffff81616972>] usbhid_disconnect+0x22/0x50 [ 234.454883] [<ffffffff81568597>] usb_unbind_interface+0x77/0x2b0 [ 234.454914] [<ffffffff814f18bf>] __device_release_driver+0x7f/0xf0 [ 234.454945] [<ffffffff814f1955>] device_release_driver+0x25/0x40 [ 234.454975] [<ffffffff814f121c>] bus_remove_device+0x11c/0x1a0 [ 234.455005] [<ffffffff814ed7d6>] device_del+0x136/0x1e0 [ 234.456529] [<ffffffff81565cd1>] usb_disable_device+0x91/0x2a0 [ 234.457652] [<ffffffff8155b046>] usb_disconnect+0x96/0x2e0 [ 234.458812] [<ffffffff8155d74a>] hub_thread+0xb5a/0x1840 [ 234.459947] [<ffffffff817a1ffc>] ? _raw_spin_unlock_irq+0x2c/0x60 [ 234.461043] [<ffffffff810edb10>] ? abort_exclusive_wait+0xb0/0xb0 [ 234.462179] [<ffffffff8155cbf0>] ? hub_port_debounce+0x140/0x140 [ 234.463258] [<ffffffff810c1379>] kthread+0xf9/0x110 [ 234.464328] [<ffffffff810c1280>] ? insert_kthread_work+0x80/0x80 [ 234.465404] [<ffffffff817a2dfc>] ret_from_fork+0x7c/0xb0 [ 234.466437] [<ffffffff810c1280>] ? insert_kthread_work+0x80/0x80 [ 234.467431] Code: 8d 74 10 01 48 8b 87 a8 19 00 00 48 8b 53 30 48 8b 00 8b 80 70 ff ff ff c1 e0 08 84 c9 0f 85 e9 00 00 00 0d 00 00 00 80 4d 85 ff <89> 42 58 48 8b 43 30 44 89 b0 88 00 00 00 74 2e 48 8b bb 48 18 [ 234.468523] RIP [<ffffffff8161746f>] hid_submit_ctrl+0x7f/0x290 [ 234.469501] RSP <ffff8800daf83750> [ 234.470430] CR2: 0000000000000058 [ 234.478900] ---[ end trace a68f124f1f3439e3 ]--- [ 234.478904] BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:41 [ 234.478905] in_atomic(): 1, irqs_disabled(): 1, pid: 39, name: khubd [ 234.478906] INFO: lockdep is turned off. [ 234.478907] irq event stamp: 88244 [ 234.478908] hardirqs last enabled at (88243): [<ffffffff817a1fa5>] _raw_spin_unlock_irqrestore+0x65/0x90 [ 234.478912] hardirqs last disabled at (88244): [<ffffffff817a297b>] _raw_spin_lock_irqsave+0x2b/0xa0 [ 234.478914] softirqs last enabled at (88204): [<ffffffff8109cc0b>] __do_softirq+0x21b/0x4e0 [ 234.478917] softirqs last disabled at (88185): [<ffffffff8109d0b5>] irq_exit+0xc5/0xd0 [ 234.478919] Preemption disabled at:[<ffffffff816177f8>] usbhid_submit_report+0x38/0x370 [ 234.478924] CPU: 2 PID: 39 Comm: khubd Tainted: G D IO 3.16.0-rc5+ #112 [ 234.478926] Hardware name: Microsoft Corporation Surface Pro 2/Surface Pro 2, BIOS 2.03.0250 09/06/2013 [ 234.478927] ffffffff81a4e169 ffff8800daf833b8 ffffffff8179924a 0000000000000000 [ 234.478929] ffff8800daf833e0 ffffffff810cbf20 ffff880118a6e2b8 ffff880118a6e328 [ 234.478932] ffff8800daf836a8 ffff8800daf83408 ffffffff817a056a ffff8800daf83418 [ 234.478934] Call Trace: [ 234.478937] [<ffffffff8179924a>] dump_stack+0x4e/0x7a [ 234.478940] [<ffffffff810cbf20>] __might_sleep+0x170/0x260 [ 234.478942] [<ffffffff817a056a>] down_read+0x2a/0xa0 [ 234.478946] [<ffffffff810ad004>] exit_signals+0x24/0x130 [ 234.478948] [<ffffffff81098d0d>] do_exit+0xbd/0xd90 [ 234.478952] [<ffffffff8110ee35>] ? kmsg_dump+0x145/0x210 [ 234.478954] [<ffffffff8110ed12>] ? kmsg_dump+0x22/0x210 [ 234.478958] [<ffffffff8101e99b>] oops_end+0x9b/0xe0 [ 234.478961] [<ffffffff81061c8c>] no_context+0x12c/0x300 [ 234.478963] [<ffffffff81061eed>] __bad_area_nosemaphore+0x8d/0x220 [ 234.478965] [<ffffffff81062093>] bad_area_nosemaphore+0x13/0x20 [ 234.478967] [<ffffffff8106242e>] __do_page_fault+0xce/0x620 [ 234.478970] [<ffffffff810ed684>] ? __wake_up+0x44/0x50 [ 234.478973] [<ffffffff813e1017>] ? debug_smp_processor_id+0x17/0x20 [ 234.478976] [<ffffffff810f623b>] ? get_lock_stats+0x2b/0x60 [ 234.478978] [<ffffffff810f63de>] ? put_lock_stats.isra.29+0xe/0x30 [ 234.478980] [<ffffffff810f681e>] ? lock_release_holdtime.part.30+0xde/0x160 [ 234.478983] [<ffffffff813d689d>] ? trace_hardirqs_off_thunk+0x3a/0x3c [ 234.478985] [<ffffffff810629a2>] do_page_fault+0x22/0x30 [ 234.478988] [<ffffffff817a4f68>] page_fault+0x28/0x30 [ 234.478991] [<ffffffff8161746f>] ? hid_submit_ctrl+0x7f/0x290 [ 234.478993] [<ffffffff81617707>] usbhid_restart_ctrl_queue+0x87/0x140 [ 234.478996] [<ffffffff81617a88>] usbhid_submit_report+0x2c8/0x370 [ 234.478998] [<ffffffff81617b4a>] usbhid_request+0x1a/0x30 [ 234.479004] [<ffffffffa020edfb>] sensor_hub_set_feature+0x8b/0xd0 [hid_sensor_hub] [ 234.479008] [<ffffffffa02d9084>] hid_sensor_power_state+0x84/0x110 [hid_sensor_trigger] [ 234.479011] [<ffffffffa02d9129>] hid_sensor_data_rdy_trigger_set_state+0x19/0x20 [hid_sensor_trigger] [ 234.479016] [<ffffffffa034d5b7>] iio_triggered_buffer_predisable+0xa7/0xb0 [industrialio] [ 234.479020] [<ffffffffa034cc4a>] iio_disable_all_buffers+0x3a/0xc0 [industrialio] [ 234.479024] [<ffffffffa03487d3>] iio_device_unregister+0x53/0x80 [industrialio] [ 234.479027] [<ffffffffa026c06a>] hid_accel_3d_remove+0x2a/0x50 [hid_sensor_accel_3d] [ 234.479030] [<ffffffff814f433d>] platform_drv_remove+0x1d/0x40 [ 234.479033] [<ffffffff814f18bf>] __device_release_driver+0x7f/0xf0 [ 234.479036] [<ffffffff814f1955>] device_release_driver+0x25/0x40 [ 234.479038] [<ffffffff814f121c>] bus_remove_device+0x11c/0x1a0 [ 234.479040] [<ffffffff814ed7d6>] device_del+0x136/0x1e0 [ 234.479042] [<ffffffff81512190>] ? mfd_cell_disable+0x80/0x80 [ 234.479045] [<ffffffff814f41d1>] platform_device_del+0x21/0xc0 [ 234.479047] [<ffffffff814f4282>] platform_device_unregister+0x12/0x30 [ 234.479049] [<ffffffff815121d3>] mfd_remove_devices_fn+0x43/0x50 [ 234.479051] [<ffffffff814ed3e3>] device_for_each_child+0x43/0x70 [ 234.479053] [<ffffffff81512105>] mfd_remove_devices+0x25/0x30 [ 234.479057] [<ffffffffa020ebd7>] sensor_hub_remove+0x87/0x140 [hid_sensor_hub] [ 234.479059] [<ffffffff81607c5b>] hid_device_remove+0x6b/0xd0 [ 234.479063] [<ffffffff814f18bf>] __device_release_driver+0x7f/0xf0 [ 234.479065] [<ffffffff814f1955>] device_release_driver+0x25/0x40 [ 234.479067] [<ffffffff814f121c>] bus_remove_device+0x11c/0x1a0 [ 234.479069] [<ffffffff814ed7d6>] device_del+0x136/0x1e0 [ 234.479071] [<ffffffff81607d47>] hid_destroy_device+0x27/0x60 [ 234.479074] [<ffffffff81616972>] usbhid_disconnect+0x22/0x50 [ 234.479076] [<ffffffff81568597>] usb_unbind_interface+0x77/0x2b0 [ 234.479079] [<ffffffff814f18bf>] __device_release_driver+0x7f/0xf0 [ 234.479081] [<ffffffff814f1955>] device_release_driver+0x25/0x40 [ 234.479083] [<ffffffff814f121c>] bus_remove_device+0x11c/0x1a0 [ 234.479085] [<ffffffff814ed7d6>] device_del+0x136/0x1e0 [ 234.479088] [<ffffffff81565cd1>] usb_disable_device+0x91/0x2a0 [ 234.479090] [<ffffffff8155b046>] usb_disconnect+0x96/0x2e0 [ 234.479092] [<ffffffff8155d74a>] hub_thread+0xb5a/0x1840 [ 234.479094] [<ffffffff817a1ffc>] ? _raw_spin_unlock_irq+0x2c/0x60 [ 234.479096] [<ffffffff810edb10>] ? abort_exclusive_wait+0xb0/0xb0 [ 234.479098] [<ffffffff8155cbf0>] ? hub_port_debounce+0x140/0x140 [ 234.479101] [<ffffffff810c1379>] kthread+0xf9/0x110 [ 234.479103] [<ffffffff810c1280>] ? insert_kthread_work+0x80/0x80 [ 234.479106] [<ffffffff817a2dfc>] ret_from_fork+0x7c/0xb0 [ 234.479107] [<ffffffff810c1280>] ? insert_kthread_work+0x80/0x80 Thanks, Reyad Attiyat -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
