On 14.5.2020 12.43, Li Jun wrote: > While remove host(e.g. for USB role switch from host to device), if > runtime pm is enabled by user, below oops are occurs at dwc3 > and cdns3 platform. Keep the xhci-plat device being active during > remove host fixes them. > > oops1: > Unable to handle kernel NULL pointer dereference at virtual address 0000000000000240 > Mem abort info: > ESR = 0x96000004 > xhci-hcd xhci-hcd.1.auto: // Halt the HC > xhci-hcd xhci-hcd.1.auto: // Reset the HC > xhci-hcd xhci-hcd.1.auto: Wait for controller to be ready for doorbell rings > EC = 0x25: DABT (current EL), IL = 32 bits > SET = 0, FnV = 0 > EA = 0, S1PTW = 0 > Data abort info: > ISV = 0, ISS = 0x00000004 > xhci-hcd xhci-hcd.1.auto: // Disabling event ring interrupts > CM = 0, WnR = 0 > user pgtable: 4k pages, 48-bit VAs, pgdp=00000001b7b18000 > xhci-hcd xhci-hcd.1.auto: cleaning up memory > xhci-hcd xhci-hcd.1.auto: Freed event ring > xhci-hcd xhci-hcd.1.auto: Freed command ring > [0000000000000240] pgd=0000000000000000 > Internal error: Oops: 96000004 [#1] PREEMPT SMP > Modules linked in: > CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.4.3-00107-g64d454a-dirty #1219 > Hardware name: FSL i.MX8MP EVK (DT) > Workqueue: pm pm_runtime_work > pstate: 60000005 (nZCv daif -PAN -UAO) > pc : xhci_suspend+0x34/0x698 > lr : xhci_plat_runtime_suspend+0x2c/0x38 > sp : ffff800011ddbbc0 > x29: ffff800011ddbbc0 x28: 0000000000000000 > x27: 0000000000000008 x26: ffff800011b28000 > x25: ffff80001012b328 x24: ffff800011ddbd48 > x23: 0000000000000000 x22: ffff80001076ed78 > x21: ffff000177896000 x20: ffff0001714ebce4 > x19: ffff000177896000 x18: ffffffffffffffff > x17: 0000000000000000 x16: 0000000000000000 > x15: ffff800011b288c8 x14: 0000000000000261 > x13: 0000000000000001 x12: 0000000000000001 > x11: 0000000000000000 x10: 00000000000009c0 > x9 : ffff800011ddbd40 x8 : fefefefefefefeff > x7 : 0000000000000000 x6 : 000000003ca92688 > x5 : 00ffffffffffffff x4 : 001b6b0b00000000 > x3 : ffff0001714ebc10 x2 : 0000000000000000 > x1 : 0000000000000001 x0 : ffff000177896250 > Call trace: > xhci_suspend+0x34/0x698 > xhci_plat_runtime_suspend+0x2c/0x38 > pm_generic_runtime_suspend+0x28/0x40 > __rpm_callback+0xd8/0x138 > rpm_callback+0x24/0x98 > rpm_suspend+0xe0/0x448 > rpm_idle+0x124/0x140 > pm_runtime_work+0xa0/0xf8 > process_one_work+0x1dc/0x370 > worker_thread+0x48/0x468 > kthread+0xf0/0x120 > ret_from_fork+0x10/0x1c > > oops2: > usb 2-1: USB disconnect, device number 2 > xhci-hcd xhci-hcd.1.auto: remove, state 4 > usb usb2: USB disconnect, device number 1 > xhci-hcd xhci-hcd.1.auto: USB bus 2 deregistered > xhci-hcd xhci-hcd.1.auto: remove, state 4 > usb usb1: USB disconnect, device number 1 > Unable to handle kernel NULL pointer dereference at virtual address 0000000000000138 > Mem abort info: > ESR = 0x96000004 > EC = 0x25: DABT (current EL), IL = 32 bits > SET = 0, FnV = 0 > EA = 0, S1PTW = 0 > Data abort info: > ISV = 0, ISS = 0x00000004 > CM = 0, WnR = 0 > user pgtable: 4k pages, 48-bit VAs, pgdp=00000008b05e8000 > [0000000000000138] pgd=0000000000000000, p4d=0000000000000000 > Internal error: Oops: 96000004 [#1] PREEMPT SMP > Modules linked in: > CPU: 2 PID: 7 Comm: kworker/u8:0 Not tainted 5.6.0-rc4-next-20200304-03578-gd6235ff42e2b #101 > Hardware name: Freescale i.MX8QXP MEK (DT) > Workqueue: 1-0050 tcpm_state_machine_work > pstate: 20000005 (nzCv daif -PAN -UAO) > pc : xhci_free_dev+0x214/0x270 > lr : xhci_plat_runtime_resume+0x78/0x88 > sp : ffff80001006b5b0 > x29: ffff80001006b5b0 x28: 0000000000000002 > x27: ffff00083b74fd48 x26: ffff00083a365580 > x25: ffff800010141458 x24: 0000000000000000 > x23: 0000000000000000 x22: ffff000837e58138 > x21: 0000000000000004 x20: ffff000837e58000 > x19: ffff000837e58250 x18: 0000000000000000 > x17: 0000000000000000 x16: 0000000000000001 > x15: 0000000000000004 x14: ffffffffffffffff > x13: 0000000000004ed8 x12: ffff8000123d1000 > x11: ffff800012158000 x10: ffff8000123d1360 > x9 : ffff800010c74b00 x8 : 0000000000000007 > x7 : 00000000000012c2 x6 : ffff8000123d1000 > x5 : 0000000000000001 x4 : 0000000000000000 > x3 : 0000000000000000 x2 : 0000000000000138 > x1 : 0000000000000000 x0 : 0000000000000138 > Call trace: > xhci_free_dev+0x214/0x270 > xhci_plat_runtime_resume+0x78/0x88 > pm_generic_runtime_resume+0x30/0x48 > __rpm_callback+0x90/0x148 > rpm_callback+0x28/0x88 > rpm_resume+0x568/0x758 > rpm_resume+0x260/0x758 > rpm_resume+0x260/0x758 > __pm_runtime_resume+0x40/0x88 > device_release_driver_internal+0xa0/0x1c8 > device_release_driver+0x1c/0x28 > bus_remove_device+0xd4/0x158 > device_del+0x15c/0x3a0 > usb_disable_device+0xb0/0x268 > usb_disconnect+0xcc/0x300 > usb_remove_hcd+0xf4/0x1dc > xhci_plat_remove+0x78/0xe0 > platform_drv_remove+0x30/0x50 > device_release_driver_internal+0xfc/0x1c8 > device_release_driver+0x1c/0x28 > bus_remove_device+0xd4/0x158 > device_del+0x15c/0x3a0 > platform_device_del.part.0+0x20/0x90 > platform_device_unregister+0x28/0x40 > cdns3_host_exit+0x20/0x40 > cdns3_role_stop+0x60/0x90 > cdns3_role_set+0x64/0xd8 > usb_role_switch_set_role.part.0+0x3c/0x68 > usb_role_switch_set_role+0x20/0x30 > tcpm_mux_set+0x60/0xf8 > tcpm_reset_port+0xa4/0xf0 > tcpm_detach.part.0+0x28/0x50 > tcpm_state_machine_work+0x12ac/0x2360 > process_one_work+0x1c8/0x470 > worker_thread+0x50/0x428 > kthread+0xfc/0x128 > ret_from_fork+0x10/0x18 > Code: c8037c02 35ffffa3 17ffe7c3 f9800011 (c85f7c01) > ---[ end trace 45b1a173d2679e44 ]--- > > Cc: Baolin Wang <baolin.wang@xxxxxxxxxx> > Cc: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> > Cc: <stable@xxxxxxxxxxxxxxx> > Fixes: b0c69b4bace3 ("usb: host: plat: Enable xHCI plat runtime PM") > Reviewed-by: Peter Chen <peter.chen@xxxxxxx> > Tested-by: Peter Chen <peter.chen@xxxxxxx> > Signed-off-by: Li Jun <jun.li@xxxxxxx> > --- > changes for v2: > - Add pm_runtime_put_noidle() to balance pm_runtime_get_sync(). > - Move pm_runtime_set_suspended() to be after pm_runtime_disable(). Thanks, added to queue. did some minor modification to the commit message at the same time. -Mathias