linux-kernel - Re: [PATCH 1/1] staging: rtl8723au: Remove unnecessary OOM message

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Date:	Fri, 06 Mar 2015 12:21:53 -0800
From:	Joe Perches <joe@...ches.com>
To:	Jes Sorensen <Jes.Sorensen@...hat.com>
Cc:	Julia Lawall <julia.lawall@...6.fr>,
	Quentin Lambert <lambert.quentin@...il.com>,
	Larry Finger <Larry.Finger@...inger.net>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	kernel-janitors@...r.kernel.org, linux-wireless@...r.kernel.org,
	devel@...verdev.osuosl.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/1] staging: rtl8723au: Remove unnecessary OOM message

On Fri, 2015-03-06 at 14:43 -0500, Jes Sorensen wrote:
> Joe Perches <joe@...ches.com> writes:
> > On Fri, 2015-03-06 at 11:08 -0500, Jes Sorensen wrote:
> >> Julia Lawall <julia.lawall@...6.fr> writes:
> >> > On Fri, 6 Mar 2015, Jes Sorensen wrote:
> >> >> Quentin Lambert <lambert.quentin@...il.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,

Jes,

> That is bologna,

We disagree, and I rather like minced meat sausages.

> 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.

Likely enough of this is emitted by the generic OOM
message and stack dump.

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

cheesy tomato/tomahto.  Goes well with baloney.

cheers, Joe

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