linux-kernel - Re: [PATCH v2 2/3] lib/vsprintf: Replace custom spec to print decimals with generic one

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Date:   Fri, 31 Jul 2020 16:48:09 -0400
From:   Steven Rostedt <rostedt@...dmis.org>
To:     Joe Perches <joe@...ches.com>
Cc:     Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Petr Mladek <pmladek@...e.com>,
        Sergey Senozhatsky <sergey.senozhatsky@...il.com>,
        linux-kernel@...r.kernel.org,
        Rasmus Villemoes <linux@...musvillemoes.dk>,
        Pantelis Antoniou <pantelis.antoniou@...sulko.com>,
        Rob Herring <robh@...nel.org>,
        Grant Likely <grant.likely@....com>
Subject: Re: [PATCH v2 2/3] lib/vsprintf: Replace custom spec to print
 decimals with generic one

On Fri, 31 Jul 2020 11:20:21 -0700
Joe Perches <joe@...ches.com> wrote:

> On Fri, 2020-07-31 at 21:08 +0300, Andy Shevchenko wrote:
> > When printing phandle via %pOFp the custom spec is used. First of all,
> > it has a SMALL flag which makes no sense for decimal numbers. Second,
> > we have already default spec for decimal numbers. Use the latter in
> > the %pOFp case as well.  
> []
> > diff --git a/lib/vsprintf.c b/lib/vsprintf.c  
> []
> > @@ -1979,12 +1979,6 @@ char *device_node_string(char *buf, char *end, struct device_node *dn,
> >  	char *buf_start = buf;
> >  	struct property *prop;
> >  	bool has_mult, pass;
> > -	static const struct printf_spec num_spec = {
> > -		.flags = SMALL,
> > -		.field_width = -1,
> > -		.precision = -1,
> > -		.base = 10,
> > -	};
> >  
> >  	struct printf_spec str_spec = spec;
> >  	str_spec.field_width = -1;
> > @@ -2024,7 +2018,7 @@ char *device_node_string(char *buf, char *end, struct device_node *dn,
> >  			str_spec.precision = precision;
> >  			break;
> >  		case 'p':	/* phandle */
> > -			buf = number(buf, end, (unsigned int)dn->phandle, num_spec);
> > +			buf = number(buf, end, (unsigned int)dn->phandle, default_dec_spec);  
> 
> Could changing .precision = -1 to 0 change any output?
> 

static const struct printf_spec default_dec_spec = {
	.base = 10,
	.precision = -1,
};


It's the field_width that changes from -1 to 0, which shouldn't cause
any issue.

-- Steve