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Subject: Re: [PATCH] staging: rtl8723bs: Revert ignoring_unreachable_code
 kfree
From: Bastien Nocera <hadess@hadess.net>
To: Ian W MORRISON <ianwmorrison@gmail.com>
Cc: linux-wireless@vger.kernel.org,
        Larry Finger <Larry.Finger@lwfinger.net>,
        jes.sorensen@gmail.com, Hans de Goede <hdegoede@redhat.com>,
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Date: Thu, 27 Apr 2017 16:05:43 +0200
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On Fri, 2017-04-28 at 00:00 +1000, Ian W MORRISON wrote:
> With the current code from linux-next an 'insmod r8723bs.ko'
> immediately results in segmentation fault.

What's the error trace you get?

>  If I apply my 'patch' the insmod works and wifi is perfect. I didn't
> try removing the kfree() call altogether as I didn't feel I had
> enough understanding of possible implications to do so.
> 
> On 27 April 2017 at 23:47, Bastien Nocera <hadess@hadess.net> wrote:
> > On Thu, 2017-04-27 at 23:44 +1000, Ian W MORRISON wrote:
> > > I tried building the RTL8723BS SDIO wifi driver which has just
> > been
> > > incorporated in staging for linux-next as an external module and
> > > found that it fails with 'Segmentation Fault'. I've tracked this
> > down
> > > to commit 6557ddfec348c13d7798ea9e44f11b6459f2f652 (staging:
> > > rtl8723bs: Fix various errors in os_dep/ioctl_cfg80211.c) which
> > > includes the fix
> > > 'drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c:3547
> > > rtw_wdev_alloc() info: ignoring unreachable code'. The moving of
> > line
> > > 'kfree((u8 *)wdev);' causes the segmentation error so I've
> > included
> > > the following patch to revert it.
> > 
> > What error? Both versions look equally incorrect, eg. either it's
> > leaking data in which case the kfree() is necessary and should be
> > in a
> > callable location, or it's not, and the call should be removed.
> > 
> 
>