[PATCH 5.18 0796/1095] staging: fbtft: core: set smem_len before fb_deferred_io_init call

Greg Kroah-Hartman
2022-08-15T22:30:18Z

From: Peter Suti <peter.suti@streamunlimited.com>

[ Upstream commit 81e878887ff82a7dd42f22951391069a5d520627 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/staging/fbtft/fbtft-core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/fbtft/fbtft-core.c b/drivers/staging/fbtft/fbtft-core.c
index 9c4d797e7ae4..4137c1a51e1b 100644
--- a/drivers/staging/fbtft/fbtft-core.c
+++ b/drivers/staging/fbtft/fbtft-core.c
@@ -656,7 +656,6 @@ struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
fbdefio->delay = HZ / fps;
fbdefio->sort_pagelist = 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;
@@ -667,6 +666,7 @@ 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;
--
2.35.1