staging: fbtft: core: set smem_len before fb_deferred_io_init call

commit 81e878887ff82a7dd42f22951391069a5d520627 upstream.

The fbtft_framebuffer_alloc() calls fb_deferred_io_init() before
initializing info->fix.smem_len.  It is set to zero by the
framebuffer_alloc() function.  It will trigger a WARN_ON() at the
start of fb_deferred_io_init() and the function will not do anything.

Fixes: 856082f021a2 ("fbdev: defio: fix the pagelist corruption")
Signed-off-by: Peter Suti <peter.suti@streamunlimited.com>
Link: https://lore.kernel.org/r/20220727073550.1491126-1-peter.suti@streamunlimited.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/fbtft/fbtft-core.c b/drivers/staging/fbtft/fbtft-core.c
index 7aec35ae5cd51350462eca2dd795a40f258d0cf7..810ed1fca10b6c1212fcdd6ff65cc2fb3d52ef01 100644 (file)
--- a/drivers/staging/fbtft/fbtft-core.c
+++ b/drivers/staging/fbtft/fbtft-core.c
@@ -657,7 +657,6 @@ struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
        fbdefio->delay =            HZ / fps;
        fbdefio->sort_pagereflist = true;
        fbdefio->deferred_io =      fbtft_deferred_io;
-       fb_deferred_io_init(info);
 
        snprintf(info->fix.id, sizeof(info->fix.id), "%s", dev->driver->name);
        info->fix.type =           FB_TYPE_PACKED_PIXELS;
@@ -668,6 +667,7 @@ struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
        info->fix.line_length =    width * bpp / 8;
        info->fix.accel =          FB_ACCEL_NONE;
        info->fix.smem_len =       vmem_size;
+       fb_deferred_io_init(info);
 
        info->var.rotate =         pdata->rotate;
        info->var.xres =           width;