4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tony Lindgren <tony@xxxxxxxxxxx> [ Upstream commit 3ba7b7795b7e8889af1377904c55c7fae9e0c775 ] While testing musb host mode cable plugging on a BeagleBone, I came across this error: Unhandled fault: external abort on non-linefetch (0x1008) at 0xd1dcfc60 ... [<bf668390>] (musb_default_readb [musb_hdrc]) from [<bf668578>] (musb_irq_work+0x1c/0x180 [musb_hdrc]) [<bf668578>] (musb_irq_work [musb_hdrc]) from [<c0156554>] (process_one_work+0x2b4/0x808) [<c0156554>] (process_one_work) from [<c015767c>] (worker_thread+0x3c/0x550) [<c015767c>] (worker_thread) from [<c015d568>] (kthread+0x104/0x148) [<c015d568>] (kthread) from [<c01078d0>] (ret_from_fork+0x14/0x24) Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> Signed-off-by: Bin Liu <b-liu@xxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/musb/musb_core.c | 11 +++++++++++ 1 file changed, 11 insertions(+) --- a/drivers/usb/musb/musb_core.c +++ b/drivers/usb/musb/musb_core.c @@ -1909,6 +1909,14 @@ static void musb_pm_runtime_check_sessio static void musb_irq_work(struct work_struct *data) { struct musb *musb = container_of(data, struct musb, irq_work.work); + int error; + + error = pm_runtime_get_sync(musb->controller); + if (error < 0) { + dev_err(musb->controller, "Could not enable: %i\n", error); + + return; + } musb_pm_runtime_check_session(musb); @@ -1916,6 +1924,9 @@ static void musb_irq_work(struct work_st musb->xceiv_old_state = musb->xceiv->otg->state; sysfs_notify(&musb->controller->kobj, NULL, "mode"); } + + pm_runtime_mark_last_busy(musb->controller); + pm_runtime_put_autosuspend(musb->controller); } static void musb_recover_from_babble(struct musb *musb)