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Message-ID: <1359017171.18561.29.camel@suxuemin.sh.intel.com>
Subject: Re: [PATCH V3] drm_crtc: check if fb_create return NULL
From: "Su, Xuemin" <xuemin.su@intel.com>
To: Jani Nikula <jani.nikula@linux.intel.com>
Cc: airlied@linux.ie, dri-devel@lists.freedesktop.org,
        linux-kernel@vger.kernel.org, yanmin_zhang@linux.intel.com,
        bo.he@intel.com
Date: Thu, 24 Jan 2013 16:46:11 +0800
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	 <87bocfugln.fsf@intel.com>
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On Thu, 2013-01-24 at 10:31 +0200, Jani Nikula wrote:
> >  	}
> > +	/* some buggy driver may return NULL here, which may cause panic */
> > +	BUG_ON(!fb);
> 
> I fail to see the benefit of this compared to just letting it oops...
> 
> >  	or->fb_id = fb->base.id;
> 
> ...right here.
> 
> 
For PATCH V3, I think a BUG_ON may give the user clearer information
about the reason of panic. Easier to debug.
I submitted a PATCH V2 yesterday which gives a warning and then return
-EVAL if fb==NULL, preventing the panic. Do you think this is
acceptable?