Re: [PATCH v10 0/6] Re-introduce TX FIFO resize for larger EP bursting

From: Andy Shevchenko
Date: Thu Aug 19 2021 - 03:55:56 EST


On Wed, Aug 18, 2021 at 10:07 PM Ferry Toth <fntoth@xxxxxxxxx> wrote:
> Op 18-08-2021 om 00:00 schreef Ferry Toth:
> > Op 16-08-2021 om 07:18 schreef Felipe Balbi:
> >> 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://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html
> >>>>>>>>>>
> >>>>>>>>>>
> >>>>>>>>>> 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://www.kernel.org/doc/html/latest/driver-api/usb/dwc3.html#reporting-bugs
> >>>>>>>>> <https://www.kernel.org/doc/html/latest/driver-api/usb/dwc3.html#reporting-bugs>
> >>>>>>>>>
> >>>>>>>>>
> >>>>>>>>> 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?

Since it's rc6 to rc7 I think the best is to send a revert series to
handle the regression.

> >>> With 5.14.0-rc5 the problem seems worse (or different?), and just
> >>> disabling uac2 gadget does not prevent the crash. Even disabling gser
> >>> and mass_storage.usb0 as well there is still a crash.
> >>>
> >>> Now I'm not sure how to proceed. Bisect rc1? Or focus on rc5 (rc6?)?
> >> I'd first bisect between 5.13 and v5.14-rc1. Once you find the offending
> >> commit, verify if reverting that on -rc1 works, then verify if reverting
> >> on -rc5 also works :-)

--
With Best Regards,
Andy Shevchenko