Commit af5d0f7e authored by Antonino A. Daplas's avatar Antonino A. Daplas Committed by Linus Torvalds
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[PATCH] fbdev: Reduce stack usage 



calc_mode_timings() and fb_get_mode() are using more than 500 bytes off the
stack.  Fix.

Signed-off-by: default avatarAntonino Daplas <adaplas@pol.net>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 0a484a3a

drivers/video/fbmon.c

+68 −58
Original line number Diff line number Diff line
@@ -317,26 +317,29 @@ static int edid_is_monitor_block(unsigned char *block) 
static void calc_mode_timings(int xres, int yres, int refresh,

			      struct fb_videomode *mode)

{

	struct fb_var_screeninfo var;

	struct fb_info info;

	struct fb_var_screeninfo *var;

	

	memset(&var, 0, sizeof(struct fb_var_screeninfo));

	var.xres = xres;

	var.yres = yres;

	var = kzalloc(sizeof(struct fb_var_screeninfo), GFP_KERNEL);



	if (var) {

		var->xres = xres;

		var->yres = yres;

		fb_get_mode(FB_VSYNCTIMINGS | FB_IGNOREMON,

		    refresh, &var, &info);

			    refresh, var, NULL);

		mode->xres = xres;

		mode->yres = yres;

	mode->pixclock = var.pixclock;

		mode->pixclock = var->pixclock;

		mode->refresh = refresh;

	mode->left_margin = var.left_margin;

	mode->right_margin = var.right_margin;

	mode->upper_margin = var.upper_margin;

	mode->lower_margin = var.lower_margin;

	mode->hsync_len = var.hsync_len;

	mode->vsync_len = var.vsync_len;

		mode->left_margin = var->left_margin;

		mode->right_margin = var->right_margin;

		mode->upper_margin = var->upper_margin;

		mode->lower_margin = var->lower_margin;

		mode->hsync_len = var->hsync_len;

		mode->vsync_len = var->vsync_len;

		mode->vmode = 0;

		mode->sync = 0;

		kfree(var);

	}

}



static int get_est_timing(unsigned char *block, struct fb_videomode *mode)
@@ -1105,15 +1108,21 @@ static void fb_timings_dclk(struct __fb_timings *timings) 
 */ 

int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var, struct fb_info *info)

{

	struct __fb_timings timings;

	struct __fb_timings *timings;

	u32 interlace = 1, dscan = 1;

	u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;

	u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax, err = 0;





	timings = kzalloc(sizeof(struct __fb_timings), GFP_KERNEL);



	if (!timings)

		return -ENOMEM;



	/* 

	 * If monspecs are invalid, use values that are enough

	 * for 640x480@60

	 */

	if (!info->monspecs.hfmax || !info->monspecs.vfmax ||

	if (!info || !info->monspecs.hfmax || !info->monspecs.vfmax ||

	    !info->monspecs.dclkmax ||

	    info->monspecs.hfmax < info->monspecs.hfmin ||

	    info->monspecs.vfmax < info->monspecs.vfmin ||
@@ -1130,65 +1139,66 @@ int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var, struct fb_inf 
		dclkmax = info->monspecs.dclkmax;

	}



	memset(&timings, 0, sizeof(struct __fb_timings));

	timings.hactive = var->xres;

	timings.vactive = var->yres;

	timings->hactive = var->xres;

	timings->vactive = var->yres;

	if (var->vmode & FB_VMODE_INTERLACED) { 

		timings.vactive /= 2;

		timings->vactive /= 2;

		interlace = 2;

	}

	if (var->vmode & FB_VMODE_DOUBLE) {

		timings.vactive *= 2;

		timings->vactive *= 2;

		dscan = 2;

	}



	switch (flags & ~FB_IGNOREMON) {

	case FB_MAXTIMINGS: /* maximize refresh rate */

		timings.hfreq = hfmax;

		fb_timings_hfreq(&timings);

		if (timings.vfreq > vfmax) {

			timings.vfreq = vfmax;

			fb_timings_vfreq(&timings);

		timings->hfreq = hfmax;

		fb_timings_hfreq(timings);

		if (timings->vfreq > vfmax) {

			timings->vfreq = vfmax;

			fb_timings_vfreq(timings);

		}

		if (timings.dclk > dclkmax) {

			timings.dclk = dclkmax;

			fb_timings_dclk(&timings);

		if (timings->dclk > dclkmax) {

			timings->dclk = dclkmax;

			fb_timings_dclk(timings);

		}

		break;

	case FB_VSYNCTIMINGS: /* vrefresh driven */

		timings.vfreq = val;

		fb_timings_vfreq(&timings);

		timings->vfreq = val;

		fb_timings_vfreq(timings);

		break;

	case FB_HSYNCTIMINGS: /* hsync driven */

		timings.hfreq = val;

		fb_timings_hfreq(&timings);

		timings->hfreq = val;

		fb_timings_hfreq(timings);

		break;

	case FB_DCLKTIMINGS: /* pixelclock driven */

		timings.dclk = PICOS2KHZ(val) * 1000;

		fb_timings_dclk(&timings);

		timings->dclk = PICOS2KHZ(val) * 1000;

		fb_timings_dclk(timings);

		break;

	default:

		return -EINVAL;

		err = -EINVAL;

		

	} 

	

	if (!(flags & FB_IGNOREMON) && 

	    (timings.vfreq < vfmin || timings.vfreq > vfmax || 

	     timings.hfreq < hfmin || timings.hfreq > hfmax ||

	     timings.dclk < dclkmin || timings.dclk > dclkmax))

		return -EINVAL;



	var->pixclock = KHZ2PICOS(timings.dclk/1000);

	var->hsync_len = (timings.htotal * 8)/100;

	var->right_margin = (timings.hblank/2) - var->hsync_len;

	var->left_margin = timings.hblank - var->right_margin - var->hsync_len;

	

	if (err || (!(flags & FB_IGNOREMON) &&

	    (timings->vfreq < vfmin || timings->vfreq > vfmax ||

	     timings->hfreq < hfmin || timings->hfreq > hfmax ||

	     timings->dclk < dclkmin || timings->dclk > dclkmax))) {

		err = -EINVAL;

	} else {

		var->pixclock = KHZ2PICOS(timings->dclk/1000);

		var->hsync_len = (timings->htotal * 8)/100;

		var->right_margin = (timings->hblank/2) - var->hsync_len;

		var->left_margin = timings->hblank - var->right_margin -

			var->hsync_len;

		var->vsync_len = (3 * interlace)/dscan;

		var->lower_margin = (1 * interlace)/dscan;

	var->upper_margin = (timings.vblank * interlace)/dscan - 

		var->upper_margin = (timings->vblank * interlace)/dscan -

			(var->vsync_len + var->lower_margin);

	}

	

	return 0;

	kfree(timings);

	return err;

}

#else

int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)

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