linux-kernel - Re: [PATCH v1 6/7] test_hexdump: test all possible group sizes for overflow

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Message-ID: <1448037839.31665.172.camel@linux.intel.com>
Date:	Fri, 20 Nov 2015 18:43:59 +0200
From:	Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:	Rasmus Villemoes <linux@...musvillemoes.dk>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH v1 6/7] test_hexdump: test all possible group sizes for
 overflow

On Thu, 2015-11-19 at 11:14 +0100, Rasmus Villemoes wrote:
> On Wed, Nov 11 2015, Andy Shevchenko <andriy.shevchenko@...ux.intel.c
> om> wrote:
> 
> > Currently only one combination is tested for overflow, i.e. rowsize
> > = 16,
> > groupsize = 1, len = 1.  Do various test to go all possible
> > branches.

[]

> > +	do {
> > +		int gs = 1 << i;
> > +		size_t len = get_random_int() % 16 + gs;
> > +
> > +		test_hexdump_overflow(buflen, rounddown(len, gs),
> > 16, gs, ascii);
> > +	} while (i++ < 3);
> > +}
> 
> 
> aren't you missing a
> 
>   test_hexdump_overflow(buflen, rounddown(len, gs), 32, gs, ascii);
> 
> here to also exercise the rowsize==32 code?

I could add that as well, though it seems minor since the idea is to go
for all branches, which 16 covers anyway.

>  static int __init test_hexdump_init(void)
> >  {
> >  	unsigned int i;
> > @@ -186,10 +199,10 @@ static int __init test_hexdump_init(void)
> >  		test_hexdump_set(rowsize, true);
> >  
> >  	for (i = 0; i <= TEST_HEXDUMP_BUF_SIZE; i++)
> > -		test_hexdump_overflow(i, false);
> > +		test_hexdump_overflow_set(i, false);
> >  
> >  	for (i = 0; i <= TEST_HEXDUMP_BUF_SIZE; i++)
> > -		test_hexdump_overflow(i, true);
> > +		test_hexdump_overflow_set(i, true);
> 
> It seems neater to do one loop:
> 
> for (i = 0; i <= TEST_HEXDUMP_BUF_SIZE; i++) {
>   test_hexdump_overflow_set(i, false);
>   test_hexdump_overflow_set(i, true);
> }

I would like to keep them separately, though I'm also okay to do it in
one loop.

-- 
Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Intel Finland Oy

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