Re: [PATCH v2] fbdev: platinumfb: add error checking for ioremap calls

[Helge Deller]

On 8/20/26 01:59, Nathan Chancellor wrote:
> On Tue, Aug 18, 2026 at 11:03:07AM +0200, Helge Deller wrote:
> > On 8/17/26 08:39, yuebingkun wrote:
> > > The ioremap() and ioremap_wt() calls in platinumfb_probe() were not
> > > checked for failure. If any of these mappings fail, the driver would
> > > dereference NULL pointers, leading to a kernel panic.
> > >
> > > Add proper error checking and use goto-based cleanup to avoid code
> > > duplication across the error paths.
> > >
> > > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> >
> > That Fixes line ^^^ has no value, so I dropped it.
> >
> > > Signed-off-by: yuebingkun <yuebingkun@xxxxxxxxxx>
> >
> > Would be nice to have your Name written out here, e.g. Yue Bing Kun (or something),
> > but I've left it as-is for now. In case you resend with full name, I can replace it
> > in the git tree.
> >
> > >    drivers/video/fbdev/platinumfb.c | 36 ++++++++++++++++++++++++++------
> > >    1 file changed, 30 insertions(+), 6 deletions(-)
> > Patch applied (with the Fixes line dropped).
>
> This patch introduces a compiler warning for me:
>
>    drivers/video/fbdev/platinumfb.c: In function 'platinumfb_probe':
>    drivers/video/fbdev/platinumfb.c:650:1: warning: label 'err_unmap_regs' defined but not used [-Wunused-label]
>      650 | err_unmap_regs:
>          | ^~~~~~~~~~~~~~
>
> As far as I can tell, it is unnecessary, so maybe this could be folded
> in? Otherwise, I can send a formal patch.

I've folded it into the existing patch!

Thank you, Nathan!
Helge


> diff --git a/drivers/video/fbdev/platinumfb.c b/drivers/video/fbdev/platinumfb.c
> index f74c937c839f..81fdaa3541db 100644
> --- a/drivers/video/fbdev/platinumfb.c
> +++ b/drivers/video/fbdev/platinumfb.c
> @@ -647,7 +647,6 @@ static int platinumfb_probe(struct platform_device* odev)
>   	iounmap(pinfo->cmap_regs);
>   err_release_cmap:
>   	release_mem_region(pinfo->cmap_regs_phys, 0x1000);
> -err_unmap_regs:
>   	iounmap(pinfo->platinum_regs);
>   err_unmap_fb:
>   	iounmap(pinfo->frame_buffer);