Re: [PATCH 04/13] ARM: k3: r5: add proper error handling

[Marco Felsch <m.felsch@pengutronix.de>]

On 25-03-11, Sascha Hauer wrote:
> On Mon, Mar 10, 2025 at 07:52:17PM +0100, Marco Felsch wrote:
> > On 25-02-28, Sascha Hauer wrote:
> > > Add missing error handling in the image loading code. Properly check for
> > > errors and panic when mandatory binaries are missing instead of blindly
> > > continuing.
> > > 
> > > Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> > > ---
> > >  arch/arm/mach-k3/r5.c | 57 ++++++++++++++++++++++++++++-----------------------
> > >  1 file changed, 31 insertions(+), 26 deletions(-)
> > > 
> > > diff --git a/arch/arm/mach-k3/r5.c b/arch/arm/mach-k3/r5.c
> > > index 2418e9ae73..e12c888afa 100644
> > > --- a/arch/arm/mach-k3/r5.c
> > > +++ b/arch/arm/mach-k3/r5.c
> > > @@ -283,7 +283,7 @@ static int load_fip(const char *filename, off_t offset)
> > >  	return 0;
> > >  }
> > >  
> > > -static void do_dfu(void)
> > > +static int do_dfu(void)
> > >  {
> > >  	struct usbgadget_funcs funcs = {};
> > >  	int ret;
> > > @@ -293,37 +293,24 @@ static void do_dfu(void)
> > >  	funcs.dfu_opts = "/fip.img(fip)cs";
> > >  
> > >  	ret = usbgadget_prepare_register(&funcs);
> > > -	if (ret)
> > > -		goto err;
> > > +	if (ret) {
> > > +		pr_err("DFU failed with: %pe\n", ERR_PTR(ret));
> > > +		return ret;
> > > +	}
> > >  
> > >  	while (1) {
> > >  		ret = stat("/fip.img", &s);
> > >  		if (!ret) {
> > >  			printf("Downloaded FIP image, DFU done\n");
> > > -			load_fip("/fip.img", 0);
> > > -			break;
> > > +			ret = load_fip("/fip.img", 0);
> > > +			if (!ret)
> > > +				return 0;
> > >  		}
> > >  
> > >  		command_slice_release();
> > >  		mdelay(50);
> > >  		command_slice_acquire();
> > >  	};
> > > -
> > > -	return;
> > > -
> > > -err:
> > > -	pr_err("DFU failed with: %pe\n", ERR_PTR(ret));
> > > -}
> > > -
> > > -static int load_images(void)
> > > -{
> > > -	int err;
> > > -
> > > -	err = load_fip("/boot/k3.fip", 0);
> > > -	if (!err)
> > > -		return 0;
> > > -
> > > -	return 0;
> > >  }
> > 
> > Removing load_images should go into patch-3.
> 
> I deliberately did it in this patch because load_images already does
> error checking, but up to now the return value of load_images() wasn't
> checked. By doing it like you suggest I would either end up calling
> load_fip() without checking the error, or I would introduce an
> incomplete error checking in k3_r5_start_image() where the return value
> of load_fip() is checked, but not the return values of do_dfu and
> load_fip_emmc().

Ah okay, good point. In that case I'm fine with it.

Regards,
  Marco


> 
> > >  static int load_fip_emmc(void)
> > > @@ -332,6 +319,7 @@ static int load_fip_emmc(void)
> > >  	struct mci *mci;
> > >  	char *fname;
> > >  	const char *mmcdev = "mmc0";
> > > +	int ret;
> > 
> > Nit: Sometimes you do use ret, sometimes err. I would like to align it
> > if possible.
> 
> Changed to 'ret' consistently.
> 
> Sascha
> 
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