On Thu, Aug 26, 2021 at 08:57:37PM +0200, Ferry Toth wrote: > This reverts commit e89bb4288378b85c82212b60dc98ecda6b3d3a70. > > The commit is part of a series with commit > 24f779dac8f3efb9629adc0e486914d93dc45517 causing a BUG on dwc3 > hardware, at least on Intel Merrifield platform when configured > through configfs: > BUG: kernel NULL pointer dereference, address: 0000000000000008 > ... > RIP: 0010:dwc3_gadget_del_and_unmap_request+0x19/0xe0 > ... > Call Trace: > dwc3_remove_requests.constprop.0+0x12f/0x170 > __dwc3_gadget_ep_disable+0x7a/0x160 > dwc3_gadget_ep_disable+0x3d/0xd0 > usb_ep_disable+0x1c/0x70 > u_audio_stop_capture+0x79/0x120 [u_audio] > afunc_set_alt+0x73/0x80 [usb_f_uac2] > composite_setup+0x224/0x1b90 [libcomposite] > > Pavel's suggestion to add > `echo "adaptive" > functions/uac2.usb0/c_sync` to the configfs script > resolves the issue. > Thinh suggests "the crash is probably because of f_uac2 prematurely > freeing feedback request before its completion. usb_ep_dequeue() is > asynchronous. dwc2() may treat it as a synchronous call so you didn't > get a crash." > > Revert as this is a regression and the kernel shouldn't crash depending > on configuration parameters. Are these normal configuration options in the wild, or is this just something that you "can do"? > Signed-off-by: Ferry Toth <ftoth@xxxxxxxxxxxxxx> I need an ack from the original authors to revert all this... thanks, greg k-h