Messages in this thread | | | From | Robert Jarzmik <> | Subject | Re: [PATCH 1/2] usb: gadget: r8a66597: Fix two possible sleep-in-atomic-context bugs in init_controller() | Date | Fri, 29 Jun 2018 08:48:46 +0200 |
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Felipe Balbi <balbi@kernel.org> writes:
> Hi, > > Robert Jarzmik <robert.jarzmik@free.fr> writes: > >> Jia-Ju Bai <baijiaju1990@gmail.com> writes: >> >>> The driver may sleep with holding a spinlock. >>> The function call paths (from bottom to top) in Linux-4.16.7 are: >>> >>> [FUNC] msleep >>> drivers/usb/gadget/udc/r8a66597-udc.c, 839: >>> msleep in init_controller >>> drivers/usb/gadget/udc/r8a66597-udc.c, 96: >>> init_controller in r8a66597_usb_disconnect >>> drivers/usb/gadget/udc/r8a66597-udc.c, 93: >>> spin_lock in r8a66597_usb_disconnect >> >> That should not happen... >> >> If think the issue you have is that your usb_connect() and usb_disconnect() are >> called from interrupt context. I think the proper fix, as what is done in most >> udc phys, is to schedule a workqueue, see drivers/usb/phy/phy-gpio-vbus-usb.c, >> gpio_vbus_data.vbus. > > argh, no. No workqueues needed here. Sorry Technically why ?
And as bonus question, why is it better to have mdelay() calls in the driver ?
Cheers.
-- Robert
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