Re: [PATCH] staging: fbtft: add typecast in call to vfree()

[Dan Carpenter <dan.carpenter@oracle.com>]

On Thu, Oct 01, 2015 at 03:00:12PM +0200, Lars Svensson wrote:
> Member screen_base in struct fb_info is declared __iomem causing
> a sparse warning as below when passed to vfree(). This adds typecast
> (__force void *) to silence the warning.
> 
> fbtft-core.c:922:39: warning: incorrect type in argument 1 \
> (different address spaces)
> fbtft-core.c:922:39:    expected void const *addr
> fbtft-core.c:922:39:    got char [noderef] <asn:2>*screen_base
> 

I thought we were going to do something like this:

diff --git a/include/linux/fb.h b/include/linux/fb.h
index be40dba..3324c92 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -483,7 +483,10 @@ struct fb_info {
 #ifdef CONFIG_FB_TILEBLITTING
 	struct fb_tile_ops *tileops;    /* Tile Blitting */
 #endif
-	char __iomem *screen_base;	/* Virtual address */
+	union {
+		char __iomem *screen_base;	/* Virtual address */
+		char *fake_screen_base;
+	};
 	unsigned long screen_size;	/* Amount of ioremapped VRAM or 0 */ 
 	void *pseudo_palette;		/* Fake palette of 16 colors */ 
 #define FBINFO_STATE_RUNNING	0

The only question is what to call the fake_screen_base.

regards,
dan carpenter