linux-kernel - Re: [PATCH v3 2/3] video: fbdev: vesafb: add missing mtrr

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Date:	Wed, 20 May 2015 21:46:32 +0200
From:	"Luis R. Rodriguez" <mcgrof@...e.com>
To:	Tomi Valkeinen <tomi.valkeinen@...com>
Cc:	"Luis R. Rodriguez" <mcgrof@...not-panic.com>,
	plagnioj@...osoft.com, hpa@...or.com, linux-fbdev@...r.kernel.org,
	luto@...capital.net, cocci@...teme.lip6.fr,
	Toshi Kani <toshi.kani@...com>,
	Suresh Siddha <sbsiddha@...il.com>,
	Ingo Molnar <mingo@...e.hu>,
	Thomas Gleixner <tglx@...utronix.de>,
	Juergen Gross <jgross@...e.com>,
	Daniel Vetter <daniel.vetter@...ll.ch>,
	Dave Airlie <airlied@...hat.com>,
	Antonino Daplas <adaplas@...il.com>,
	Rob Clark <robdclark@...il.com>,
	Jingoo Han <jg1.han@...sung.com>,
	Wolfram Sang <wsa@...-dreams.de>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3 2/3] video: fbdev: vesafb: add missing mtrr_del() for
 added MTRR

On Wed, May 20, 2015 at 12:52:14PM +0300, Tomi Valkeinen wrote:
> Hi Luis,
> 
> On 21/04/15 23:40, Luis R. Rodriguez wrote:
> > From: "Luis R. Rodriguez" <mcgrof@...e.com>
> > 
> > The MTRR added was never being deleted.
> > 
> > Cc: Toshi Kani <toshi.kani@...com>
> > Cc: Suresh Siddha <sbsiddha@...il.com>
> > Cc: Ingo Molnar <mingo@...e.hu>
> > Cc: Thomas Gleixner <tglx@...utronix.de>
> > Cc: Juergen Gross <jgross@...e.com>
> > Cc: Daniel Vetter <daniel.vetter@...ll.ch>
> > Cc: Andy Lutomirski <luto@...capital.net>
> > Cc: Dave Airlie <airlied@...hat.com>
> > Cc: Antonino Daplas <adaplas@...il.com>
> > Cc: Rob Clark <robdclark@...il.com>
> > Cc: Jingoo Han <jg1.han@...sung.com>
> > Cc: Wolfram Sang <wsa@...-dreams.de>
> > Cc: Jean-Christophe Plagniol-Villard <plagnioj@...osoft.com>
> > Cc: Tomi Valkeinen <tomi.valkeinen@...com>
> > Cc: linux-fbdev@...r.kernel.org
> > Cc: linux-kernel@...r.kernel.org
> > Signed-off-by: Luis R. Rodriguez <mcgrof@...e.com>
> > ---
> >  drivers/video/fbdev/vesafb.c | 30 ++++++++++++++++++++++++------
> >  1 file changed, 24 insertions(+), 6 deletions(-)
> > 
> > diff --git a/drivers/video/fbdev/vesafb.c b/drivers/video/fbdev/vesafb.c
> > index 191156b..a2261d0 100644
> > --- a/drivers/video/fbdev/vesafb.c
> > +++ b/drivers/video/fbdev/vesafb.c
> > @@ -29,6 +29,10 @@
> >  
> >  /* --------------------------------------------------------------------- */
> >  
> > +struct vesafb_par {
> > +	int wc_cookie;
> > +};
> > +
> >  static struct fb_var_screeninfo vesafb_defined = {
> >  	.activate	= FB_ACTIVATE_NOW,
> >  	.height		= -1,
> > @@ -175,7 +179,16 @@ static int vesafb_setcolreg(unsigned regno, unsigned red, unsigned green,
> >  
> >  static void vesafb_destroy(struct fb_info *info)
> >  {
> > +#ifdef CONFIG_MTRR
> > +	struct vesafb_par *par = info->par;
> > +#endif
> > +
> >  	fb_dealloc_cmap(&info->cmap);
> > +
> > +#ifdef CONFIG_MTRR
> > +	if (par->wc_cookie >= 0)
> > +		mtrr_del(par->wc_cookie, 0, 0);
> > +#endif
> >  	if (info->screen_base)
> >  		iounmap(info->screen_base);
> >  	release_mem_region(info->apertures->ranges[0].base, info->apertures->ranges[0].size);
> > @@ -228,6 +241,7 @@ static int vesafb_setup(char *options)
> >  static int vesafb_probe(struct platform_device *dev)
> >  {
> >  	struct fb_info *info;
> > +	struct vesafb_par *par;
> >  	int i, err;
> >  	unsigned int size_vmode;
> >  	unsigned int size_remap;
> > @@ -297,8 +311,8 @@ static int vesafb_probe(struct platform_device *dev)
> >  		return -ENOMEM;
> >  	}
> >  	platform_set_drvdata(dev, info);
> > -	info->pseudo_palette = info->par;
> > -	info->par = NULL;
> > +	info->pseudo_palette = NULL;
> > +	par = info->par;
> >  
> >  	/* set vesafb aperture size for generic probing */
> >  	info->apertures = alloc_apertures(1);
> > @@ -407,17 +421,17 @@ static int vesafb_probe(struct platform_device *dev)
> >  	if (mtrr == 3) {
> >  #ifdef CONFIG_MTRR
> >  		unsigned int temp_size = size_total;
> > -		int rc;
> >  
> >  		/* Find the largest power-of-two */
> >  		temp_size = roundup_pow_of_two(temp_size);
> >  
> >  		/* Try and find a power of two to add */
> >  		do {
> > -			rc = mtrr_add(vesafb_fix.smem_start, temp_size,
> > -				      MTRR_TYPE_WRCOMB, 1);
> > +			par->wc_cookie = mtrr_add(vesafb_fix.smem_start,
> > +						  temp_size,
> > +						  MTRR_TYPE_WRCOMB, 1);
> >  			temp_size >>= 1;
> > -		} while (temp_size >= PAGE_SIZE && rc == -EINVAL);
> > +		} while (temp_size >= PAGE_SIZE && par->wc_cookie == -EINVAL);
> >  #endif
> >  		info->screen_base = ioremap_wc(vesafb_fix.smem_start, vesafb_fix.smem_len);
> >  	} else {
> > @@ -462,6 +476,10 @@ static int vesafb_probe(struct platform_device *dev)
> >  	fb_info(info, "%s frame buffer device\n", info->fix.id);
> >  	return 0;
> >  err:
> > +#ifdef CONFIG_MTRR
> > +	if (par->wc_cookie >= 0)
> > +		mtrr_del(par->wc_cookie, 0, 0);
> > +#endif
> >  	if (info->screen_base)
> >  		iounmap(info->screen_base);
> >  	framebuffer_release(info);
> 
> Hmm, this looks a bit odd... You're removing the pseudo_palette, and
> using its memory for mtrr cookie?

You are totally right, sorry, will spin a v3.

  Luis
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