From: Li Jun jun.li@nxp.com
commit 1449cb2c2253d37d998c3714aa9b95416d16d379 upstream.
While removing the host (e.g. for USB role switch from host to device), if runtime pm is enabled by user, below oops occurs on dwc3 and cdns3 platforms. Keeping the xhci-plat device active during host removal, and disabling runtime pm before calling pm_runtime_set_suspended() fixes them.
oops1: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000240 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 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 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 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 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 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 ]---
[minor commit message cleanup -Mathias] Cc: Baolin Wang baolin.wang@linaro.org Cc: stable@vger.kernel.org Fixes: b0c69b4bace3 ("usb: host: plat: Enable xHCI plat runtime PM") Reviewed-by: Peter Chen peter.chen@nxp.com Tested-by: Peter Chen peter.chen@nxp.com Signed-off-by: Li Jun jun.li@nxp.com Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com Link: https://lore.kernel.org/r/20200514110432.25564-3-mathias.nyman@linux.intel.c... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/host/xhci-plat.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c index 9602241..adc437c 100644 --- a/drivers/usb/host/xhci-plat.c +++ b/drivers/usb/host/xhci-plat.c @@ -361,6 +361,7 @@ static int xhci_plat_remove(struct platform_device *dev) struct clk *reg_clk = xhci->reg_clk; struct usb_hcd *shared_hcd = xhci->shared_hcd;
+ pm_runtime_get_sync(&dev->dev); xhci->xhc_state |= XHCI_STATE_REMOVING;
usb_remove_hcd(shared_hcd); @@ -374,8 +375,9 @@ static int xhci_plat_remove(struct platform_device *dev) clk_disable_unprepare(reg_clk); usb_put_hcd(hcd);
- pm_runtime_set_suspended(&dev->dev); pm_runtime_disable(&dev->dev); + pm_runtime_put_noidle(&dev->dev); + pm_runtime_set_suspended(&dev->dev);
return 0; }