Re: [BUG] mfd: ezx-pcap: Possible sleep-in-atomic-context bugs in pcap_adc_irq()

[Jia-Ju Bai]

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?


Best wishes,
Jia-Ju Bai