On 20-03-10 09:57:00, Alan Stern wrote:
On Tue, 10 Mar 2020, Peter Chen wrote:
From: Peter Chen peter.chen@nxp.com
The code calls pm_runtime_get_sync with irq disabled, it causes below warning:
BUG: sleeping function called from invalid context at wer/runtime.c:1075 in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: er/u8:1
...
Tested-by: Dmitry Osipenko digetx@gmail.com Cc: stable@vger.kernel.org #v5.5 Fixes: 72dc8df7920f ("usb: chipidea: udc: protect usb interrupt enable") Reported-by: Dmitry Osipenko digetx@gmail.com Signed-off-by: Peter Chen peter.chen@nxp.com
drivers/usb/chipidea/udc.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c index ffaf46f5d062..1fa587ec52fc 100644 --- a/drivers/usb/chipidea/udc.c +++ b/drivers/usb/chipidea/udc.c @@ -1539,9 +1539,11 @@ static void ci_hdrc_gadget_connect(struct usb_gadget *_gadget, int is_active) if (ci->driver) { hw_device_state(ci, ci->ep0out->qh.dma); usb_gadget_set_state(_gadget, USB_STATE_POWERED);
spin_unlock_irqrestore(&ci->lock, flags); usb_udc_vbus_handler(_gadget, true);} else {spin_unlock_irqrestore(&ci->lock, flags);
spin_unlock_irqrestore(&ci->lock, flags);There's something strange about this patch.
Do you really know that interrupts will be enabled following the spin_unlock_irqrestore()? In other words, do you know that interrupts were enabled upon entry to this routine?
If they were, then why use spin_lock_irqsave/spin_unlock_irqrestore? Why not use spin_lock_irq and spin_unlock_irq?
This function is called at process context, so the interrupt is enabled, I will use spin_lock_irq, thanks, Alan.