Re: BUG: scheduling while atomic in f_fs when gadget remove driver

From: Michal Nazarewicz <mina86@mina86.com>
To: John Stultz <john.stultz@linaro.org>
Cc: Chen Yu <chenyu56@huawei.com>,
	Felipe Balbi <felipe.balbi@linux.intel.com>,
	Greg KH <gregkh@linuxfoundation.org>,
	Biggo Wang <wangbinghui@hisilicon.com>,
	lkml <linux-kernel@vger.kernel.org>,
	linux-usb@vger.kernel.org, Amit Pundir <amit.pundir@linaro.org>,
	Guodong Xu <guodong.xu@linaro.org>
Subject: Re: BUG: scheduling while atomic in f_fs when gadget remove driver
Date: Mon, 03 Oct 2016 22:07:32 +0200	[thread overview]
Message-ID: <xa1tint9qjqz.fsf@mina86.com> (raw)
In-Reply-To: <CALAqxLW0scq+WxcEZEojdap_UdN7r0aEV6+KxsZ4H2WFXHVXcQ@mail.gmail.com>

On Mon, Oct 03 2016, John Stultz wrote:
> On Wed, Sep 28, 2016 at 2:38 PM, Michal Nazarewicz <mina86@mina86.com> wrote:
>> On Wed, Sep 28 2016, Michal Nazarewicz wrote:
>>> With that done, the only thing which needs a mutex is
>>> epfile->read_buffer.
>>
>> Perhaps this would do:
>>
>> ---- >8 -------------------------------------------------- -------------
>> From 6416a1065203a39328311f6c58083089efe169aa Mon Sep 17 00:00:00 2001
>> From: Michal Nazarewicz <mina86@mina86.com>
>> Date: Wed, 28 Sep 2016 23:36:56 +0200
>> Subject: [RFC] usb: gadget: f_fs: stop sleeping in ffs_func_eps_disable
>> MIME-Version: 1.0
>> Content-Type: text/plain; charset=UTF-8
>> Content-Transfer-Encoding: 8bit
>>
>> ffs_func_eps_disable is called from atomic context so it cannot sleep
>> thus cannot grab a mutex.  Change the handling of epfile->read_buffer
>> to use non-sleeping synchronisation method.
>>
>> Reported-by: Chen Yu <chenyu56@huawei.com>
>> Signed-off-by: Michał Nazarewicz <mina86@mina86.com>
>> Fixes: 9353afbbfa7b ("buffer data from ‘oversized’ OUT requests")
>
> So the patch here seems to be in some odd encoding?

O_o
It’s UTF-8.

> Can you resend it using git-send-email or in some way other then
> embedding it inline here? Maybe just point me to a git tree that has
> it?

	https://github.com/mina86/linux.git f-fs-fix

Regardless, I’ll prepare a proper patchset within a few days.  Maybe
even now.

-- 
Best regards
ミハウ “𝓶𝓲𝓷𝓪86” ナザレヴイツ
«If at first you don’t succeed, give up skydiving»