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From: Jes Sorensen <Jes.Sorensen@redhat.com>
To: Joe Perches <joe@perches.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>,
        Quentin Lambert <lambert.quentin@gmail.com>,
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Subject: Re: [PATCH 1/1] staging: rtl8723au: Remove unnecessary OOM message
References: <20150306082140.GA9740@sloth>
	<wrfjh9tyywm4.fsf@ultrasam.lan.trained-monkey.org>
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	<wrfj61aeyup1.fsf@ultrasam.lan.trained-monkey.org>
	<1425663302.12017.32.camel@perches.com>
Date: Fri, 06 Mar 2015 14:43:09 -0500
In-Reply-To: <1425663302.12017.32.camel@perches.com> (Joe Perches's message of
	"Fri, 06 Mar 2015 09:35:02 -0800")
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Joe Perches <joe@perches.com> writes:
> On Fri, 2015-03-06 at 11:08 -0500, Jes Sorensen wrote:
>> Julia Lawall <julia.lawall@lip6.fr> writes:
>> > On Fri, 6 Mar 2015, Jes Sorensen wrote:
>> >> Quentin Lambert <lambert.quentin@gmail.com> writes:
>> >> > This patch reduces the kernel size by removing error messages
>> >> > that duplicate
>> >> > the normal OOM message.
>> >> > A simplified version of the semantic patch that finds this problem is as
>> >> > follows: (http://coccinelle.lip6.fr)
>> >> This patch removes useful warnings about what allocation failed. The
>> >> messages removed are NOT duplicate!
>> > Is it really the case that the information can't be reconstructed from the
>> > information generated by kmalloc on failure?  To my understanding there is
>> > a stack trace, and from scanning through the changes I see only one change
>> > per function, so perhaps the stack trace already makes it clear where the
>> > problem occurred?
>> It may be possible to backtrack, but this change just makes it harder.
>> There are tons of real issues to fix in this driver, this patch just
>> increases the risk of patch conflicts for no real gain.
>
> Making the allocation less likely to fail for
> low memory systems is a gain.
>
> The allocation failures themselves are low
> likelihood events.  Determining which specific
> memory allocation failure occurred has near
> nil value.

Joe,

That is bologna, knowing which allocation failed has a lot of value, it
allows the developer to go back and look at the allocation sizes,
parameters applied etc.

This is a classic case of blindly applied script 'fixes' causing more
harm than good.

Jes