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Date:   Mon, 3 May 2021 11:01:41 -0700
From:   Daniel Walker <danielwa@cisco.com>
To:     Christophe Leroy <christophe.leroy@csgroup.eu>
Cc:     linuxppc-dev@lists.ozlabs.org, x86@kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        xe-linux-external@cisco.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/3] lib: early_string: allow early usage of some string
 functions
Message-ID: <20210503180141.GO3844417@zorba>
References: <20210430042217.1198052-1-danielwa@cisco.com>
 <dc26a67e-dba0-1b8c-3718-3c75415c61f1@csgroup.eu>
 <1929b3a8-f882-c930-4b99-10c6a8f127c7@csgroup.eu>
 <e355ecc9-574a-dbcb-7864-5aa4974e1971@csgroup.eu>
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On Sat, May 01, 2021 at 09:31:47AM +0200, Christophe Leroy wrote:
> 
> > In fact, should be like in prom_init today:
> > 
> > #ifdef __EARLY_STRING_ENABLED
> >  ????if (dsize >= count)
> >  ??????? return count;
> > #else
> >  ????BUG_ON(dsize >= count);
> > #endif
> 
> Thinking about it once more, this BUG_ON() is overkill and should be
> avoided, see https://www.kernel.org/doc/html/latest/process/deprecated.html
> 
> Therefore, something like the following would make it:
> 
> 	if (dsize >= count) {
> 		WARN_ON(!__is_defined(__EARLY_STRING_ENABLED));
> 
> 		return count;
> 	}

I agree, it's overkill it stop the system for this condition.

how about I do something more like this for my changes,


> 	if (WARN_ON(dsize >= count && !__is_defined(__EARLY_STRING_ENABLED)))
> 		return count;

and for generic kernel,

> 	if (WARN_ON(dsize >= count))
> 		return count;


Daniel