Re: [PATCH] printk: handle blank console arguments passed in.

From: Sergey Senozhatsky
Date: Mon Mar 16 2020 - 22:01:58 EST


On (20/03/16 21:39), Steven Rostedt wrote:
[..]
> >
> > diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index ad4606234545..e9ad730991e0 100644
> > --- a/kernel/printk/printk.c
> > +++ b/kernel/printk/printk.c
> > @@ -2165,7 +2165,10 @@ static int __init console_setup(char *str)
> > char buf[sizeof(console_cmdline[0].name) + 4]; /* 4 for "ttyS" */
> > char *s, *options, *brl_options = NULL;
> > int idx;
> > -
> > + if (str[0] == 0) {
> > + console_loglevel = 0;
> > + return 1;
>
> Hmm, I wonder if this should produce a warning :-/

Hmm. Maybe the warning can seat in __setup() handling?
There are 300+ places that theoretically can receive blank boot param

$ git grep "__setup(\".*=\"" | wc -l
307

I'd assume that not all of those can handle blank params. At the same
time, do we have cases when passing blank boot params is OK? E.g.
"... root=/dev/sda1 foo= bar= ..."

-ss