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Date:   Wed, 20 Jun 2018 13:22:49 +0300
From:   Dan Carpenter <dan.carpenter@oracle.com>
To:     Jia-Ju Bai <baijiaju1990@gmail.com>
Cc:     cocci@systeme.lip6.fr, Julia Lawall <Julia.Lawall@lip6.fr>,
        gregkh@linuxfoundation.org, quytelda@tamalin.org,
        Larry.Finger@lwfinger.net, harshasharmaiitr@gmail.com,
        arushisinghal19971997@gmail.com, amitoj1606@gmail.com,
        jeremy.lefaure@lse.epita.fr, teo.dacquet@gmail.com,
        devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] staging: rtl8723bs: Fix two possible
 sleep-in-atomic-context bugs in translate_scan()
Message-ID: <20180620102249.djwmdv34zp5vyj2h@mwanda>
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On Wed, Jun 20, 2018 at 06:05:06PM +0800, Jia-Ju Bai wrote:
> > Thanks!  It occurs to me that another way to detect this bug is that
> > one of the allocations in this function already uses GFP_ATOMIC.  It
> > doesn't normally make sense to mix GFP_ATOMIC and GFP_KERNEL when there
> > isn't any locking in the function.
> 
> Yes, this pattern is interesting for bug finding :)
> But to fix the bugs of this pattern, we need to decide whether GFP_ATOMIC or
> GFP_KERNEL should be used here.
> 

Sure.  But either way it's a bug. Plus this would be the first static
checker warning which warns about using GFP_ATOMIC when it's supposed to
be GFP_KERNEL.  #milestone

regards,
dan carpenter