From: Felipe Balbi <balbi@kernel.org>
To: Robert Jarzmik <robert.jarzmik@free.fr>,
Jia-Ju Bai <baijiaju1990@gmail.com>
Cc: gregkh@linuxfoundation.org, nicolas.ferre@microchip.com,
keescook@chromium.org, allen.lkml@gmail.com,
linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] usb: gadget: r8a66597: Fix two possible sleep-in-atomic-context bugs in init_controller()
Date: Fri, 29 Jun 2018 09:35:10 +0300 [thread overview]
Message-ID: <87y3eydrs1.fsf@linux.intel.com> (raw)
In-Reply-To: <87efh0o6f9.fsf@belgarion.home>
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
--
balbi
next prev parent reply other threads:[~2018-06-29 6:38 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-06-20 3:54 [PATCH 1/2] usb: gadget: r8a66597: Fix two possible sleep-in-atomic-context bugs in init_controller() Jia-Ju Bai
2018-06-21 9:06 ` Robert Jarzmik
2018-06-29 6:35 ` Felipe Balbi [this message]
2018-06-29 6:48 ` Robert Jarzmik
2018-06-29 10:25 ` Felipe Balbi
2018-06-29 11:04 ` Robert Jarzmik
2018-06-29 11:15 ` Felipe Balbi
2018-06-29 13:21 ` Robert Jarzmik
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