simplefb: fix unmapping fb during destruction (498f6d36) · Commits · 戴 / test

Unfortunately, fbdev does not create its own "struct device" for framebuffers. Instead, it attaches to the device of the parent layer. This has the side-effect that devm_* managed resources are not cleaned up on framebuffer-destruction but rather during destruction of the parent-device. In case of fbdev this might be too late, though. remove_conflicting_framebuffer() may remove fbdev devices but keep the parent device as it is. Therefore, we now use plain ioremap() and unmap the framebuffer in the fb_destroy() callback. Note that we must not free the device here as this might race with the parent-device removal. Instead, we rely on unregister_framebuffer() as barrier and we're safe. Reported-by:

Tom Gundersen <teg@jklm.no> Signed-off-by:

David Herrmann <dh.herrmann@gmail.com> Acked-by:

Stephen Warren <swarren@nvidia.com> Signed-off-by:

Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/video/simplefb.c

+10 −2

Original line number	Diff line number	Diff line
		@@ -66,8 +66,15 @@ static int simplefb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
		return 0;
		}

		static void simplefb_destroy(struct fb_info *info)
		{
		if (info->screen_base)
		iounmap(info->screen_base);
		}

		static struct fb_ops simplefb_ops = {
		.owner = THIS_MODULE,
		.fb_destroy = simplefb_destroy,
		.fb_setcolreg = simplefb_setcolreg,
		.fb_fillrect = cfb_fillrect,
		.fb_copyarea = cfb_copyarea,
		@@ -212,7 +219,7 @@ static int simplefb_probe(struct platform_device *pdev)

		info->fbops = &simplefb_ops;
		info->flags = FBINFO_DEFAULT \| FBINFO_MISC_FIRMWARE;
		info->screen_base = devm_ioremap(&pdev->dev, info->fix.smem_start,
		info->screen_base = ioremap(info->fix.smem_start,
		info->fix.smem_len);
		if (!info->screen_base) {
		framebuffer_release(info);
		@@ -231,6 +238,7 @@ static int simplefb_probe(struct platform_device *pdev)
		ret = register_framebuffer(info);
		if (ret < 0) {
		dev_err(&pdev->dev, "Unable to register simplefb: %d\n", ret);
		iounmap(info->screen_base);
		framebuffer_release(info);
		return ret;
		}

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