On 9/15/23 18:35, Avichal Rakesh wrote: > > > On 9/15/23 16:16, Michael Grzeschik wrote: >> Hi Avichal >> >> On Thu, Sep 14, 2023 at 04:05:36PM -0700, Avichal Rakesh wrote: >>> On Mon, Sep 11, 2023 at 9:19 PM Avichal Rakesh <arakesh@xxxxxxxxxx> wrote: >>>> >>>> We have been seeing two main bugs when stopping stream: >>>> 1. attempting to queue usb_requests on a disabled usb endpoint, and >>>> 2. use-after-free problems for inflight requests >>>> >>>> Avichal Rakesh (2): >>>> usb: gadget: uvc: prevent use of disabled endpoint >>>> usb: gadget: uvc: prevent de-allocating inflight usb_requests >>>> >>>> drivers/usb/gadget/function/f_uvc.c | 11 ++++---- >>>> drivers/usb/gadget/function/f_uvc.h | 2 +- >>>> drivers/usb/gadget/function/uvc.h | 5 +++- >>>> drivers/usb/gadget/function/uvc_v4l2.c | 21 ++++++++++++--- >>>> drivers/usb/gadget/function/uvc_video.c | 34 +++++++++++++++++++++++-- >>>> 5 files changed, 60 insertions(+), 13 deletions(-) >>>> >>> >>> Bumping this thread up. Laurent, Dan, and Michael could you take a look? >> >> I tested the patches against my setup and it did not help. > > Thank you for testing the patch, I really appreciate your help in testing the > patches! > >> >> In fact I saw two different issues when calling the streamoff event. >> >> One issue was a stalled pipeline after the streamoff from the host came in. >> The streaming application did not handle any events anymore. > > This sounds like uvc_function_setup_continue was never called, so no more control > events were queued for the userspace to handle. This is a little bit of a shot in > the dark: if you are not using the Laurent's uvc-gadget > (https://git.ideasonboard.org/uvc-gadget.git) on the gadget, could you check that > your userspace application (on the gadget side) calls VIDIOC_STREAMOFF when > handling UVC_EVENT_STREAMOFF? > > This is similar to how it should called VIDIOC_STREAMON when handling > UVC_EVENT_STREAMON. Before my patch, I think UVC gadget driver is functionally fine > with userspace application not calling VIDIOC_STREAMOFF. However, my patch prevents > the host from making any more control requests until the gadget's userspace > application calls VIDIOC_STREAMOFF, which looks like a stalled control ep. > >> >> The second issue was when the streamoff event is triggered sometimes the >> following trace is shown, even with your patches applied. >> >> >> [ 104.202689] Unable to handle kernel paging request at virtual address 005bf43a692a5fd5 >> [ 104.235122] Mem abort info: >> [ 104.238257] ESR = 0x0000000096000004 >> [ 104.242449] EC = 0x25: DABT (current EL), IL = 32 bits >> [ 104.248391] SET = 0, FnV = 0 >> [ 104.251803] EA = 0, S1PTW = 0 >> [ 104.255313] FSC = 0x04: level 0 translation fault >> [ 104.260765] Data abort info: >> [ 104.263982] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 >> [ 104.270114] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 >> [ 104.275760] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 >> [ 104.281698] [005bf43a692a5fd5] address between user and kernel address ranges >> [ 104.290042] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP >> [ 104.297060] Dumping ftrace buffer: >> [ 104.300869] (ftrace buffer empty) >> [ 104.304862] Modules linked in: st1232 hantro_vpu v4l2_vp9 v4l2_h264 uio_pdrv_genirq fuse [last unloaded: rockchip_vpu(C)] >> [ 104.312080] panfrost fde60000.gpu: Panfrost Dump: BO has no sgt, cannot dump >> [ 104.317137] CPU: 0 PID: 465 Comm: irq/46-dwc3 Tainted: G C 6.5.0-20230831-2+ #5 >> [ 104.317144] Hardware name: WolfVision PF5 (DT) >> [ 104.317148] pstate: 604000c9 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) >> [ 104.317154] pc : __list_del_entry_valid+0x48/0xe8 >> [ 104.352728] lr : dwc3_gadget_giveback+0x3c/0x1b0 >> [ 104.357893] sp : ffffffc08381bc60 >> [ 104.361593] x29: ffffffc08381bc60 x28: ffffff80047d4000 x27: ffffff80047de440 >> [ 104.369576] x26: 0000000000000000 x25: ffffffc08135b2d0 x24: ffffffc08381bd00 >> [ 104.377559] x23: 00000000ffffff98 x22: ffffff8004204880 x21: ffffff80047d4000 >> [ 104.385541] x20: ffffff800718dea0 x19: ffffff800718dea0 x18: 0000000000000000 >> [ 104.393523] x17: 7461747320687469 x16: 7720646574656c70 x15: 6d6f632074736575 >> [ 104.401504] x14: 716572205356203a x13: 2e3430312d207375 x12: 7461747320687469 >> [ 104.409486] x11: ffffffc0815c98f0 x10: 0000000000000000 x9 : ffffffc0808f4fa0 >> [ 104.417468] x8 : ffffffc082415000 x7 : ffffffc0808f4e2c x6 : ffffffc0823d0928 >> [ 104.425450] x5 : 0000000000000282 x4 : 0000000000000201 x3 : d85bf43a692a5fcd >> [ 104.433431] x2 : ffffff80047d4048 x1 : ffffff800718dea0 x0 : dead000000000122 >> [ 104.441413] Call trace: >> [ 104.444142] __list_del_entry_valid+0x48/0xe8 >> [ 104.449013] dwc3_gadget_giveback+0x3c/0x1b0 >> [ 104.453786] dwc3_gadget_ep_cleanup_cancelled_requests+0xe0/0x170 >> [ 104.460599] dwc3_process_event_buf+0x2a8/0xbb0 >> [ 104.465662] dwc3_thread_interrupt+0x4c/0x90 >> [ 104.470435] irq_thread_fn+0x34/0xb8 >> [ 104.474431] irq_thread+0x1a0/0x290 >> [ 104.478327] kthread+0x10c/0x120 >> [ 104.481933] ret_from_fork+0x10/0x20 >> >> The error path triggering these list errors are usually in the >> dwc3 driver handling the cancelled or completed list. > > It looks like we're still freeing un-returned requests :(. If you still have > the setup can you pull the uvc logs to see if waiting for requests to be returned timed > out? I wonder if dwc3's interrupt handler is being scheduled too late. 500ms seemed > like a reasonable time out to me, but this seems to prove otherwise. > Hey Michael, were you able to look into the comments from the previous email? Avi.
