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Date:   Tue, 9 Oct 2018 02:07:15 -0700
From:   Lee Jones <lee.jones@linaro.org>
To:     Jia-Ju Bai <baijiaju1990@gmail.com>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [BUG] mfd: ezx-pcap: Possible sleep-in-atomic-context bugs in
 pcap_adc_irq()
Message-ID: <20181009090715.GE4939@dell>
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On Mon, 17 Sep 2018, Jia-Ju Bai wrote:

> 
> 
> On 2018/9/17 9:03, Lee Jones wrote:
> > On Sat, 15 Sep 2018, Jia-Ju Bai wrote:
> > 
> > > The driver may sleep in an interrupt handler.
> > > The function call paths (from bottom to top) in Linux-4.17 are:
> > > 
> > > [FUNC] mutex_lock_nested
> > > drivers/mfd/ezx-pcap.c, 272:
> > >      mutex_lock_nested in pcap_adc_irq (interrupt handler)
> > > 
> > > [FUNC] mutex_lock_nested
> > > drivers/mfd/ezx-pcap.c, 100:
> > >      mutex_lock_nested in ezx_pcap_read
> > > drivers/mfd/ezx-pcap.c, 281:
> > >      ezx_pcap_read in pcap_adc_irq (interrupt handler)
> > > 
> > > [FUNC] mutex_lock_nested
> > > drivers/mfd/ezx-pcap.c, 85:
> > >      mutex_lock_nested in ezx_pcap_write
> > > drivers/mfd/ezx-pcap.c, 285:
> > >      ezx_pcap_write in pcap_adc_irq (interrupt handler)
> > > 
> > > [FUNC] mutex_lock_nested
> > > drivers/mfd/ezx-pcap.c, 244:
> > >      mutex_lock_nested in pcap_adc_trigger
> > > drivers/mfd/ezx-pcap.c, 299:
> > >      pcap_adc_trigger in pcap_adc_irq (interrupt handler)
> > > 
> > > These bugs are found by my static analysis tool DSAC.
> > Not sure what you want me to do with this.
> > 
> > Do you have something in mind?
> > 
> 
> I find some possible bugs in this driver, but I do not know how to correctly
> fix them...
> Could you find a good solution?

If you have found bugs and do not intend on fixing them, please report
them via the 'File a Bug' option here:

  https://bugzilla.kernel.org/

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
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