On Mon, Jan 16, 2017 at 12:57 PM, John Youn <john.y...@synopsys.com> wrote: > > >> On Jan 16, 2017, at 12:37 PM, John Stultz <john.stu...@linaro.org> wrote: >> >> On Mon, Jan 16, 2017 at 2:36 AM, Felipe Balbi >> <felipe.ba...@linux.intel.com> wrote: >>> >>> Hi, >>> >>> John Stultz <john.stu...@linaro.org> writes: >>>> Basically when plugging in various cables in different orders, I'm >>>> occasionally seeing the following BUG splat: >>>> >>>> [ 86.215403] BUG: scheduling while atomic: kworker/u16:2/53/0x00000002 >>>> [ 86.219164] usb 1-1: USB disconnect, device number 9 >>>> [ 86.226845] Preemption disabled at:[ 86.230218] >>>> [<ffffff8008673558>] dwc2_conn_id_status_change+0x120/0x250 >>>> [ 86.236894] CPU: 0 PID: 53 Comm: kworker/u16:2 Tainted: G W >>>> 4.9.0-rc8-00051-gd5a7979-dirty #1702 >>>> [ 86.246836] Hardware name: HiKey Development Board (DT) >>>> [ 86.252100] Workqueue: dwc2 dwc2_conn_id_status_change >>>> [ 86.257279] Call trace: >>>> [ 86.259771] [<ffffff8008087c28>] dump_backtrace+0x0/0x1a0 >>>> [ 86.265210] [<ffffff8008087ddc>] show_stack+0x14/0x20 >>>> [ 86.270308] [<ffffff80084343f0>] dump_stack+0x90/0xb0 >>>> [ 86.275401] [<ffffff80080d8d94>] __schedule_bug+0x6c/0xb8 >>>> [ 86.280841] [<ffffff8008a07220>] __schedule+0x4f8/0x5b0 >>>> [ 86.286099] [<ffffff8008a073e8>] schedule+0x38/0xa0 >>>> [ 86.291017] [<ffffff8008a0a6cc>] >>>> schedule_hrtimeout_range_clock+0x8c/0xf0 >>>> [ 86.297846] [<ffffff8008a0a740>] schedule_hrtimeout_range+0x10/0x18 >>>> [ 86.304150] [<ffffff8008a0a4a0>] usleep_range+0x50/0x58 >>>> [ 86.309418] [<ffffff800866d8dc>] dwc2_wait_for_mode.isra.4+0x54/0xd0 >>>> [ 86.315815] [<ffffff800866f058>] dwc2_core_reset+0xe0/0x168 >>>> [ 86.321431] [<ffffff800867e364>] >>>> dwc2_hsotg_core_init_disconnected+0x2c/0x310 >>>> [ 86.328602] [<ffffff8008673568>] dwc2_conn_id_status_change+0x130/0x250 >>>> [ 86.335254] [<ffffff80080ccd48>] process_one_work+0x118/0x370 >>>> [ 86.341035] [<ffffff80080ccfe8>] worker_thread+0x48/0x498 >>>> [ 86.346473] [<ffffff80080d2eb0>] kthread+0xd0/0xe8 >>>> [ 86.351299] [<ffffff8008082e80>] ret_from_fork+0x10/0x50 >>>> >>>> This seems to be caused by the dwc2_wait_for_mode() calling >>>> usleep_range() while the hstog->lock spinlock is held, since >>>> we take that before calling dwc2_hsotg_core_init_disconnected(). >>>> >>>> This patch avoids the issue by adding an extra argument to >>>> dwc2_core_reset(), as suggested by John Youn, which allows us to >>>> skip the waiting, which should be unnecessary when calling from >>>> dwc2_hsotg_core_init_disconnected(). >>>> >>>> Cc: Wei Xu <xuw...@hisilicon.com> >>>> Cc: Guodong Xu <guodong...@linaro.org> >>>> Cc: Amit Pundir <amit.pun...@linaro.org> >>>> Cc: Rob Herring <robh...@kernel.org> >>>> Cc: John Youn <johny...@synopsys.com> >>>> Cc: Douglas Anderson <diand...@chromium.org> >>>> Cc: Chen Yu <cheny...@huawei.com> >>>> Cc: Vardan Mikayelyan <mvar...@synopsys.com> >>>> Cc: Kishon Vijay Abraham I <kis...@ti.com> >>>> Cc: Felipe Balbi <felipe.ba...@linux.intel.com> >>>> Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> >>>> Cc: linux-...@vger.kernel.org >>>> Signed-off-by: John Stultz <john.stu...@linaro.org> >>>> --- >>> >>> doesn't apply to my testing/next. Please rebase >> >> So these were rebased onto JohnY's tree here: >> >> https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_synopsys-2Dusb_linux.git&d=DwIBaQ&c=DPL6_X_6JkXFx7AXWqB0tg&r=U3o8uKoKhWme5_V9D-eeCkB11BFwt4KvWztBgdE9ZpA&m=eBJTBuJyU21iKJvHdy5FxqtxsVARo0iIqJGxMHrlbyQ&s=VIiAT32aG7s04G5NoOOthNdm2JX0eWjJpg62neY_-KI&e= >> next >> >> And apparently have been merged there. I suspect he's going to submit >> his entire tree there to you? >> >> JohnY: Is this right? > > > Yeah I'll get these issues sorted out with Felipe. Which may mean > resubmitting everything the the proper order.
Ok. Thanks for sorting this out. Please let me know if there's anything else you need from me! thanks again! -john
