Pavel Hofman wrote: > > Dne 19. 08. 21 v 22:10 Ferry Toth napsal(a): >> Hi >> >> Op 19-08-2021 om 09:51 schreef Pavel Hofman: >>> Hi, >>> >>> Dne 18. 08. 21 v 21:07 Ferry Toth napsal(a): >>>> Hi, >>>> >>>> Op 18-08-2021 om 00:00 schreef Ferry Toth: >>>>> Hi, >>>>> >>>>> Op 16-08-2021 om 07:18 schreef Felipe Balbi: >>>>>> Hi, >>>>>> >>>>>> Ferry Toth <fntoth@xxxxxxxxx> writes: >>>>>>>> Ferry Toth <fntoth@xxxxxxxxx> writes: >>>>>>>>>>>> Ferry Toth <fntoth@xxxxxxxxx> writes: >>>>>>>>>>>>>>>>> Hardware name: Intel Corporation Merrifield/BODEGA BAY, >>>>>>>>>>>>>>>>> BIOS 542 >>>>>>>>>>>>>>>>> 2015.01.21:18.19.48 >>>>>>>>>>>>>>>>> RIP: 0010:0x500000000 >>>>>>>>>>>>>>>>> Code: Unable to access opcode bytes at RIP 0x4ffffffd6. >>>>>>>>>>>>>>>>> RSP: 0018:ffffa4d00045fc28 EFLAGS: 00010046 >>>>>>>>>>>>>>>>> RAX: 0000000500000000 RBX: ffff8cd546aed200 RCX: >>>>>>>>>>>>>>>>> 0000000000000000 >>>>>>>>>>>>>>>>> RDX: 0000000000000000 RSI: ffff8cd547bfcae0 RDI: >>>>>>>>>>>>>>>>> ffff8cd546aed200 >>>>>>>>>>>>>>>>> RBP: ffff8cd547bfcae0 R08: 0000000000000000 R09: >>>>>>>>>>>>>>>>> 0000000000000001 >>>>>>>>>>>>>>>>> R10: ffff8cd541fd28c0 R11: 0000000000000000 R12: >>>>>>>>>>>>>>>>> ffff8cd547342828 >>>>>>>>>>>>>>>>> R13: ffff8cd546aed248 R14: 0000000000000000 R15: >>>>>>>>>>>>>>>>> ffff8cd548b1d000 >>>>>>>>>>>>>>>>> FS: 0000000000000000(0000) GS:ffff8cd57e200000(0000) >>>>>>>>>>>>>>>>> knlGS:0000000000000000 >>>>>>>>>>>>>>>>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >>>>>>>>>>>>>>>>> CR2: 0000000500000000 CR3: 000000000311e000 CR4: >>>>>>>>>>>>>>>>> 00000000001006f0 >>>>>>>>>>>>>>>>> Call Trace: >>>>>>>>>>>>>>>>> ? dwc3_remove_requests.constprop.0+0x14d/0x170 >>>>>>>>>>>>>>>>> ? __dwc3_gadget_ep_disable+0x7a/0x160 >>>>>>>>>>>>>>>>> ? dwc3_gadget_ep_disable+0x3d/0xd0 >>>>>>>>>>>>>>>>> ? usb_ep_disable+0x1c/0x >>>>>>>>>>>>>>>>> ? u_audio_stop_capture+0x79/0x120 [u_audio] >>>>>>>>>>>>>>>>> ? afunc_set_alt+0x73/0x80 [usb_f_uac2] >>>>>>>>>> So this is triggered by a SetInterface request... >>>>>>>>>> >>>>>>>>>>>>>>>>> ? composite_setup+0x224/0x1b90 [libcomposite] >>>>>>>>>>>>>>>>> ? __dwc3_gadget_kick_transfer+0x160/0x400 >>>>>>>>>>>>>>>>> ? dwc3_gadget_ep_queue+0xf3/0x1a0 >>>>>>>>>>>>>>>>> ? configfs_composite_setup+0x6b/0x90 >>>>>>>>>>>>>>>>> [libcomposite] >>>>>>>>>>>>>>>>> ? configfs_composite_setup+0x6b/0x90 >>>>>>>>>>>>>>>>> [libcomposite] >>>>>>>>>>>>>>>>> ? dwc3_ep0_interrupt+0x459/0xa40 >>>>>>>>>>>>>>>>> ? dwc3_thread_interrupt+0x8ee/0xf40 >>>>>>>>>>>>>>>>> ? __schedule+0x235/0x6c0 >>>>>>>>>>>>>>>>> ? disable_irq_nosync+0x10/0x10 >>>>>>>>>>>>>>>>> ? irq_thread_fn+0x1b/0x60 >>>>>>>>>>>>>>>>> ? irq_thread+0xc0/0x160 >>>>>>>>>>>>>>>>> ? irq_thread_check_affinity+0x70/0x70 >>>>>>>>>>>>>>>>> ? irq_forced_thread_fn+0x70/0x70 >>>>>>>>>>>>>>>>> ? kthread+0x122/0x140 >>>>>>>>>>>>>>>>> ? set_kthread_struct+0x40/0x40 >>>>>>>>>>>>>>>>> ? ret_from_fork+0x22/0x30 >>>>>>>>>>>>>>>> Do you mind enabling dwc3 traces and collecting them? >>>>>>>>>>>>>>>> Trying to figure >>>>>>>>>>>>>>>> out how we got here. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I'll try if I can get the same error by booting with USB >>>>>>>>>>>>>>> in host mode >>>>>>>>>>>>>>> and then switch to device mode. If so I can enable traces >>>>>>>>>>>>>>> and collect as >>>>>>>>>>>>>>> you explained me before. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I'll try before monday, as then I fly for a holiday and >>>>>>>>>>>>>>> will not be >>>>>>>>>>>>>>> available before rc5. >>>>>>>>>>>>>> you can enable all of those with kernel cmdline :-) >>>>>>>>>>>>>> >>>>>>>>>>>>>> https://urldefense.com/v3/__https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html__;!!A4F2R9G_pg!PZHOWnH3HDs-9a9bz4KLDShZpsubSfG84fu3wEZyK4Q_Wvv2lhHKuk7LJpWPAPch0qja$ ; >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> you need ftrace_dump_on_oops=1 and also need the correct >>>>>>>>>>>>>> options on >>>>>>>>>>>>>> trace_buf_size and trace_event. >>>>>>>>>>>>>> >>>>>>>>>>>>> On Edison-Arduino I have a switch to go to device mode, >>>>>>>>>>>>> after which >>>>>>>>>>>>> udev triggers a script configure gadgets through configfs. >>>>>>>>>>>>> >>>>>>>>>>>>> I tried to log following these instructions: >>>>>>>>>>>>> >>>>>>>>>>>>> https://urldefense.com/v3/__https://www.kernel.org/doc/html/latest/driver-api/usb/dwc3.html*reporting-bugs__;Iw!!A4F2R9G_pg!PZHOWnH3HDs-9a9bz4KLDShZpsubSfG84fu3wEZyK4Q_Wvv2lhHKuk7LJpWPAG64agnA$ ; >>>>>>>>>>>>> <https://urldefense.com/v3/__https://www.kernel.org/doc/html/latest/driver-api/usb/dwc3.html*reporting-bugs__;Iw!!A4F2R9G_pg!PZHOWnH3HDs-9a9bz4KLDShZpsubSfG84fu3wEZyK4Q_Wvv2lhHKuk7LJpWPAG64agnA$ >>>>>>>>>>>>> > >>>>>>>>>>>>> >>>>>>>>>>>>> Unfortunately the kernel crashes so badly I can not get to >>>>>>>>>>>>> the ` cp >>>>>>>>>>>>> /t/trace /root/trace.txt` line (after a while the watchdog >>>>>>>>>>>>> kicks). >>>>>>>>>>>>> >>>>>>>>>>>>> What to do next? >>>>>>>>>>>> Pass ftrace_dump_on_oops to kernel cmdline. >>>>>>>>>>>> >>>>>>>>>>> No sure if I did this right, on oops everything is pushed to >>>>>>>>>>> console >>>>>>>>>>> (115k2 serial), I hope nothing essential is lost. >>>>>>>>>>> >>>>>>>>>>> I copied the screen buffer to file see attached. >>>>>>>>>> Thank you, I bet it took quite a some time :-) Anyway, looking at >>>>>>>>>> the logs around Set Interface requests, we can track every >>>>>>>>>> endpoint >>>>>>>>>> that's disabled. I'll take a guess and assume we're failing at >>>>>>>>>> the last >>>>>>>>>> Set Interface, that means we should have something odd with >>>>>>>>>> ep6in, but >>>>>>>>>> everything looks fine in the trace output: >>>>>>>>>> >>>>>>>>>> [ 75.823107] irq/14-d-596 0d... 42789194us : >>>>>>>>>> dwc3_gadget_ep_enable: ep6in: mps 192/346 streams 16 burst 0 >>>>>>>>>> ring 0/0 flags E:swbp:< >>>>>>>>>> [ 75.835472] irq/14-d-596 0d... 42789198us : >>>>>>>>>> dwc3_alloc_request: ep6in: req 0000000002c71409 length 0/0 zsI >>>>>>>>>> ==> 0 >>>>>>>>>> [ 75.846416] irq/14-d-596 0d... 42789202us : >>>>>>>>>> dwc3_ep_queue: ep6in: req 0000000002c71409 length 0/192 zsI >>>>>>>>>> ==> -115 >>>>>>>>>> [ 75.857360] irq/14-d-596 0d... 42789204us : >>>>>>>>>> dwc3_alloc_request: ep6in: req 00000000a324f5d0 length 0/0 zsI >>>>>>>>>> ==> 0 >>>>>>>>>> [ 75.868301] irq/14-d-596 0d... 42789206us : >>>>>>>>>> dwc3_ep_queue: ep6in: req 00000000a324f5d0 length 0/192 zsI >>>>>>>>>> ==> -115 >>>>>>>>>> [ 75.879244] irq/14-d-596 0d... 42789209us : >>>>>>>>>> dwc3_event: event (000020c2): ep0in: Transfer Not Ready [0] >>>>>>>>>> (Not Active) [Status Phase] >>>>>>>>>> [ 75.891880] irq/14-d-596 0d... 42789211us : >>>>>>>>>> dwc3_prepare_trb: ep0in: trb 000000004c0ae319 (E0:D0) buf >>>>>>>>>> 000000001bded000 size 0 ctrl 00000c33 (HLcs:SC:status2) >>>>>>>>>> [ 75.989131] irq/14-d-596 0d... 42789224us : >>>>>>>>>> dwc3_gadget_ep_cmd: ep0in: cmd 'Start Transfer' [406] params >>>>>>>>>> 00000000 1bded000 00000000 --> status: Successful >>>>>>>>>> [ 76.096261] irq/14-d-596 0d... 42789272us : >>>>>>>>>> dwc3_event: event (0000c042): ep0in: Transfer Complete (sIL) >>>>>>>>>> [Status Phase] >>>>>>>>>> [ 76.107834] irq/14-d-596 0d... 42789275us : >>>>>>>>>> dwc3_complete_trb: ep0out: trb 000000004c0ae319 (E0:D0) buf >>>>>>>>>> 000000001bded000 size 0 ctrl 00000c32 (hLcs:SC:status2) >>>>>>>>>> [ 76.122944] irq/14-d-596 0d... 42789277us : >>>>>>>>>> dwc3_gadget_giveback: ep0out: req 00000000cb1bd3cd length 0/0 >>>>>>>>>> zsI ==> 0 >>>>>>>>>> [ 76.134160] irq/14-d-596 0d... 42789280us : >>>>>>>>>> dwc3_prepare_trb: ep0out: trb 000000004c0ae319 (E0:D0) buf >>>>>>>>>> 000000001bded000 size 8 ctrl 00000c23 (HLcs:SC:setup) >>>>>>>>>> [ 76.231322] irq/14-d-596 0d... 42789292us : >>>>>>>>>> dwc3_gadget_ep_cmd: ep0out: cmd 'Start Transfer' [406] params >>>>>>>>>> 00000000 1bded000 00000000 --> status: Successful >>>>>>>>>> [ 76.297418] kworker/-23 0d... 42789670us : >>>>>>>>>> dwc3_ep_queue: ep3in: req 0000000029586135 length 0/96 ZsI ==> >>>>>>>>>> -115 >>>>>>>>>> [ 76.308278] kworker/-23 0d... 42789695us : >>>>>>>>>> dwc3_prepare_trb: ep3in: trb 00000000b81213d6 (E1:D0) buf >>>>>>>>>> 0000000003b7a800 size 96 ctrl 00000811 (Hlcs:sC:normal) >>>>>>>>>> [ 76.395294] kworker/-23 0d... 42789707us : >>>>>>>>>> dwc3_gadget_ep_cmd: ep3in: cmd 'Update Transfer' [60007] >>>>>>>>>> params 00000000 00000000 00000000 --> status: Successful >>>>>>>>>> [ 76.471900] irq/14-d-596 0d... 42789842us : >>>>>>>>>> dwc3_event: event (0000c040): ep0out: Transfer Complete (sIL) >>>>>>>>>> [Setup Phase] >>>>>>>>>> [ 76.489308] irq/14-d-596 0d... 42789845us : >>>>>>>>>> dwc3_ctrl_req: Set Interface(Intf = 5, Alt.Setting = 0) >>>>>>>>>> [ 76.505650] irq/14-d-596 0d... 42789851us : >>>>>>>>>> dwc3_ep_dequeue: ep6in: req 0000000002c71409 length 0/192 zsI >>>>>>>>>> ==> -115 >>>>>>>>>> [ 76.523315] irq/14-d-596 0d... 42789854us : >>>>>>>>>> dwc3_gadget_giveback: ep6in: req 0000000002c71409 length 0/192 >>>>>>>>>> zsI ==> -104 >>>>>>>>>> [ 76.541427] irq/14-d-596 0d... 42789857us : >>>>>>>>>> dwc3_free_request: ep6in: req 0000000002c71409 length 0/192 >>>>>>>>>> zsI ==> -104 >>>>>>>>>> [ 76.559267] irq/14-d-596 0d... 42789859us : >>>>>>>>>> dwc3_ep_dequeue: ep6in: req 00000000a324f5d0 length 0/192 zsI >>>>>>>>>> ==> -115 >>>>>>>>>> [ 76.576937] irq/14-d-596 0d... 42789861us : >>>>>>>>>> dwc3_gadget_giveback: ep6in: req 00000000a324f5d0 length 0/192 >>>>>>>>>> zsI ==> -104 >>>>>>>>>> [ 76.595046] irq/14-d-596 0d... 42789862us : >>>>>>>>>> dwc3_free_request: ep6in: req 00000000a324f5d0 length 0/192 >>>>>>>>>> zsI ==> -104 >>>>>>>>>> [ 76.612892] irq/14-d-596 0d... 42789865us : >>>>>>>>>> dwc3_gadget_ep_disable: ep6in: mps 192/346 streams 16 burst 0 >>>>>>>>>> ring 0/0 flags E:swbp:< >>>>>>>>>> [ 76.665535] irq/14-d-596 0d... 42789873us : >>>>>>>>>> dwc3_event: event (000020c2): ep0in: Transfer Not Ready [0] >>>>>>>>>> (Not Active) [Status Phase] >>>>>>>>>> [ 76.684716] irq/14-d-596 0d... 42789875us : >>>>>>>>>> dwc3_prepare_trb: ep0in: trb 000000004c0ae319 (E0:D0) buf >>>>>>>>>> 000000001bded000 size 0 ctrl 00000c33 (HLcs:SC:status2) >>>>>>>>>> [ 76.819195] irq/14-d-596 0d... 42789886us : >>>>>>>>>> dwc3_gadget_ep_cmd: ep0in: cmd 'Start Transfer' [406] params >>>>>>>>>> 00000000 1bded000 00000000 --> status: Successful >>>>>>>>>> [ 76.926324] irq/14-d-596 0d... 42789930us : >>>>>>>>>> dwc3_event: event (0000c042): ep0in: Transfer Complete (sIL) >>>>>>>>>> [Status Phase] >>>>>>>>>> [ 76.937892] irq/14-d-596 0d... 42789933us : >>>>>>>>>> dwc3_complete_trb: ep0out: trb 000000004c0ae319 (E0:D0) buf >>>>>>>>>> 000000001bded000 size 0 ctrl 00000c32 (hLcs:SC:status2) >>>>>>>>>> [ 76.953003] irq/14-d-596 0d... 42789935us : >>>>>>>>>> dwc3_gadget_giveback: ep0out: req 00000000cb1bd3cd length 0/0 >>>>>>>>>> zsI ==> 0 >>>>>>>>>> [ 76.964217] irq/14-d-596 0d... 42789938us : >>>>>>>>>> dwc3_prepare_trb: ep0out: trb 000000004c0ae319 (E0:D0) buf >>>>>>>>>> 000000001bded000 size 8 ctrl 00000c23 (HLcs:SC:setup) >>>>>>>>>> [ 77.061379] irq/14-d-596 0d... 42789950us : >>>>>>>>>> dwc3_gadget_ep_cmd: ep0out: cmd 'Start Transfer' [406] params >>>>>>>>>> 00000000 1bded000 00000000 --> status: Successful >>>>>>>>>> [ 77.168595] irq/14-d-596 0d... 42790509us : >>>>>>>>>> dwc3_event: event (0000c040): ep0out: Transfer Complete (sIL) >>>>>>>>>> [Setup Phase] >>>>>>>>>> [ 77.180159] irq/14-d-596 0d... 42790512us : >>>>>>>>>> dwc3_ctrl_req: Get String Descriptor(Index = 18, Length = 255) >>>>>>>>>> [ 77.190578] irq/14-d-596 0d... 42790537us : >>>>>>>>>> dwc3_prepare_trb: ep0in: trb 000000004c0ae319 (E0:D0) buf >>>>>>>>>> 0000000003b68000 size 36 ctrl 00000c53 (HLcs:SC:data) >>>>>>>>>> [ 77.287648] irq/14-d-596 0d... 42790550us : >>>>>>>>>> dwc3_gadget_ep_cmd: ep0in: cmd 'Start Transfer' [406] params >>>>>>>>>> 00000000 1bded000 00000000 --> status: Successful >>>>>>>>>> [ 77.333107] irq/14-d-596 0d... 42790557us : >>>>>>>>>> dwc3_event: event (000010c2): ep0in: Transfer Not Ready [0] >>>>>>>>>> (Not Active) [Data Phase] >>>>>>>>>> [ 77.407223] irq/14-d-596 0d... 42790575us : >>>>>>>>>> dwc3_event: event (000090c2): ep0in: Transfer Not Ready [0] >>>>>>>>>> (Active) [Data Phase] >>>>>>>>>> [ 77.480985] irq/14-d-596 0d... 42790588us : >>>>>>>>>> dwc3_event: event (0000c042): ep0in: Transfer Complete (sIL) >>>>>>>>>> [Data Phase] >>>>>>>>>> [ 77.492376] irq/14-d-596 0d... 42790590us : >>>>>>>>>> dwc3_complete_trb: ep0out: trb 000000004c0ae319 (E0:D0) buf >>>>>>>>>> 0000000003b68000 size 0 ctrl 00000c52 (hLcs:SC:data) >>>>>>>>>> [ 77.507221] irq/14-d-596 0d... 42790595us : >>>>>>>>>> dwc3_gadget_giveback: ep0out: req 00000000cb1bd3cd length >>>>>>>>>> 36/36 ZsI ==> 0 >>>>>>>>>> [ 77.518609] irq/14-d-596 0d... 42790597us : >>>>>>>>>> dwc3_event: event (000020c0): ep0out: Transfer Not Ready [0] >>>>>>>>>> (Not Active) [Status Phase] >>>>>>>>>> [ 77.531332] irq/14-d-596 0d... 42790598us : >>>>>>>>>> dwc3_prepare_trb: ep0out: trb 000000004c0ae319 (E0:D0) buf >>>>>>>>>> 000000001bded000 size 0 ctrl 00000c43 (HLcs:SC:status3) >>>>>>>>>> [ 77.628669] irq/14-d-596 0d... 42790609us : >>>>>>>>>> dwc3_gadget_ep_cmd: ep0out: cmd 'Start Transfer' [406] params >>>>>>>>>> 00000000 1bded000 00000000 --> status: Successful >>>>>>>>>> >>>>>>>>>> Do you mind adding a few prints in dwc3_remove_requests to >>>>>>>>>> tell us which >>>>>>>>>> endpoint is being processed? Then we'll know for sure which >>>>>>>>>> one caused >>>>>>>>>> the crash. >>>>>>>>>> >>>>>>>>> I wouldn't mind but am leaving on a holiday, won't have time >>>>>>>>> until 6 aug. >>>>>>>> not a problem, we'll still be here when you're back :-) >>>>>>> Well, let's go then :-) >>>>>>> >>>>>>> To get back in the mood I have retested 5.13.0, 5.14.0-rc1, >>>>>>> 5.14.0-rc2 >>>>>>> and 5.14.0-rc5. >>>>>>> >>>>>>> I find that 5.13.0 works fine, and the issue starts from 5.14.0-rc1. >>>>>> That's great finding. We have a bisection point. There are a total of >>>>>> 13764 commits between v5.13 and v5.14-rc1 >>>>>> >>>>>> $ git rev-list --count v5.13..v5.14-rc1 >>>>>> 13764 >>>>>> >>>>>> git bisect should find the offending commit in at most 14 tries. >>>>>> That's >>>>>> not too bad. >>>>> I correctly guesstimated that the problem got introduced by the usb >>>>> merge 79160a60 >>>>> >>>>> "Merge tag 'usb-5.14-rc1' of >>>>> git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb" >>>>> >>>>> 116 commits(7 bisects). >>>>> >>>>> 24f779dac8f3efb9629adc0e486914d93dc45517 is the first bad commit >>>>> >>>>> "usb: gadget: f_uac2/u_audio: add feedback endpoint support" >>>>> >>>>> Ruslan's 3 patches are related to each other so I reverted all >>>>> three 24f779da...e89bb428 and applied the reverts to rc1. >>>>> >>>>> I can confirm this indeed resolves the problem in rc1. >>>>> >>>>> Is late now, tomorrow evening I will apply the reverts to rc6. >>>> >>>> With these reverts rc6 works fine as well. >>>> >>>> So, where do we go from here? >>>> >>> >>> I know the patches have been tested on dwc2 (by me and others). I do >>> not know if Ruslan or Jerome tested them on dwc3 but probably not. >>> Ruslan has talked about RPi (my case too) and BeagleboneBlack, both >>> with dwc2. Perhaps the dwc2 behaves a bit differently than dwc3? >>> >>> The patches add a new EP-IN for async feedback. I am sorry I have not >>> followed your long thread (it started as unrelated to uac). Does the >>> problem appear with f_uac1 or f_uac2? Please how have you reached the >>> above problem? >> >> I'm sorry too. I first believed the issue was related to the patch >> mentioned in the subject line. >> >> The problem appaers with f_uac2. I bost Edison_Arduino board in host >> mode (there is a switch allowing to select host/device mode). When >> flipping the switch to device mode udev run a script: >> But as I am using configfs (excerpt follows) and just disabling the >> last 2 line resolves the issue, I'm guessing uac2 is the issue. Or >> exceeding the available resources. >> >> # Create directory structure >> mkdir "${GADGET_BASE_DIR}" >> cd "${GADGET_BASE_DIR}" >> mkdir -p configs/c.1/strings/0x409 >> mkdir -p strings/0x409 >> >> # Serial device >> mkdir functions/gser.usb0 >> ln -s functions/gser.usb0 configs/c.1/ >> ### >> >> # Ethernet device >> mkdir functions/eem.usb0 >> echo "${DEV_ETH_ADDR}" > functions/eem.usb0/dev_addr >> echo "${HOST_ETH_ADDR}" > functions/eem.usb0/host_addr >> ln -s functions/eem.usb0 configs/c.1/ >> >> # Mass Storage device >> mkdir functions/mass_storage.usb0 >> echo 1 > functions/mass_storage.usb0/stall >> echo 0 > functions/mass_storage.usb0/lun.0/cdrom >> echo 0 > functions/mass_storage.usb0/lun.0/ro >> echo 0 > functions/mass_storage.usb0/lun.0/nofua >> echo "${USBDISK}" > functions/mass_storage.usb0/lun.0/file >> ln -s functions/mass_storage.usb0 configs/c.1/ >> >> # UAC2 device >> mkdir functions/uac2.usb0 >> ln -s functions/uac2.usb0 configs/c.1 >> .... >> > > As you say, could perhaps the reason be that the extra EP-IN added in > those patches (previously 1, now 2 with the default config you use) > exceeds your EP-IN max count or available fifos somehow? You have a > number of functions initialized. If you change the load order of the > functions, do you get the error later with a different function? Just > guessing... > > You should be able to switch the default async EP-OUT (which configures > the new feedback EP-IN ) to adaptive EP-OUT (which requires no feedback > EP) with c_sync=8 parameter of f_uac2. > > https://urldefense.com/v3/__https://elixir.bootlin.com/linux/v5.14-rc6/source/drivers/usb/gadget/function/f_uac2.c*L47__;Iw!!A4F2R9G_pg!PZHOWnH3HDs-9a9bz4KLDShZpsubSfG84fu3wEZyK4Q_Wvv2lhHKuk7LJpWPAHQ6Lj4y$ > > https://urldefense.com/v3/__https://elixir.bootlin.com/linux/v5.14-rc6/source/drivers/usb/gadget/function/f_uac2.c*L830__;Iw!!A4F2R9G_pg!PZHOWnH3HDs-9a9bz4KLDShZpsubSfG84fu3wEZyK4Q_Wvv2lhHKuk7LJpWPAC7mfgo7$ > > https://urldefense.com/v3/__https://elixir.bootlin.com/linux/v5.14-rc6/source/include/uapi/linux/usb/ch9.h*L453__;Iw!!A4F2R9G_pg!PZHOWnH3HDs-9a9bz4KLDShZpsubSfG84fu3wEZyK4Q_Wvv2lhHKuk7LJpWPANdeuGIx$ > > Does that fix the problem? > Hi Pavel, I took a look at 24f779dac8f3 ("usb: gadget: f_uac2/u_audio: add feedback endpoint support") that Ferry reported the issue from bisection. I see at least a couple problems in the new UAC2 changes. 1) usb_ep_dequeue() is asynchronous. Don't free requests before the controller driver give them back. 2) Did you test with SuperSpeed? I don't see companion descriptor. Please fix them. Thanks, Thinh