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From: Robert Hancock <hancockr@shaw.ca>
To: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>,
	Christoph Lameter <clameter@sgi.com>,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	akpm@linux-foundation.org
Subject: Re: [RFC 0/4] CONFIG_STABLE to switch off development checks
Date: Mon, 04 Jun 2007 18:38:14 -0600	[thread overview]
Message-ID: <4664B076.5000406@shaw.ca> (raw)
In-Reply-To: <fa.wiSgrIhkRNkkC7Wh6Bt3BY4z7BM@ifi.uio.no>

Dave Kleikamp wrote:
> I'm on Christoph's side here.  I don't think it makes sense for any code
> to ask to allocate zero bytes of memory and expect valid memory to be
> returned.
> 
> Would a compromise be to return a pointer to some known invalid region?
> This way the kmalloc(0) call would appear successful to the caller, but
> any access to the memory would result in an exception.

I would think returning 1 as the address would work here, it's not NULL 
but any access to that page should still oops..

-- 
Robert Hancock      Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@nospamshaw.ca
Home Page: http://www.roberthancock.com/


WARNING: multiple messages have this Message-ID (diff)
From: Robert Hancock <hancockr@shaw.ca>
To: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>,
	Christoph Lameter <clameter@sgi.com>,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	akpm@linux-foundation.org
Subject: Re: [RFC 0/4] CONFIG_STABLE to switch off development checks
Date: Mon, 04 Jun 2007 18:38:14 -0600	[thread overview]
Message-ID: <4664B076.5000406@shaw.ca> (raw)
In-Reply-To: <fa.wiSgrIhkRNkkC7Wh6Bt3BY4z7BM@ifi.uio.no>

Dave Kleikamp wrote:
> I'm on Christoph's side here.  I don't think it makes sense for any code
> to ask to allocate zero bytes of memory and expect valid memory to be
> returned.
> 
> Would a compromise be to return a pointer to some known invalid region?
> This way the kmalloc(0) call would appear successful to the caller, but
> any access to the memory would result in an exception.

I would think returning 1 as the address would work here, it's not NULL 
but any access to that page should still oops..

-- 
Robert Hancock      Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@nospamshaw.ca
Home Page: http://www.roberthancock.com/

--
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       reply	other threads:[~2007-06-05  0:39 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <fa.UBCbBXgIW93M6j2F+d+umQ5+v9I@ifi.uio.no>
     [not found] ` <fa.iaekQW/Par/E6eIpnL0NjEdCUxc@ifi.uio.no>
     [not found]   ` <fa.2BlkzuhauAATrsG1MYhPMeWMhPM@ifi.uio.no>
     [not found]     ` <fa.o9WA1K75HxwNnBEQDyoQMfWVpiQ@ifi.uio.no>
     [not found]       ` <fa.wiSgrIhkRNkkC7Wh6Bt3BY4z7BM@ifi.uio.no>
2007-06-05  0:38         ` Robert Hancock [this message]
2007-06-05  0:38           ` [RFC 0/4] CONFIG_STABLE to switch off development checks Robert Hancock
2007-05-31  0:20 clameter
2007-05-31  0:20 ` clameter
2007-06-01 14:55 ` Jeremy Fitzhardinge
2007-06-01 14:55   ` Jeremy Fitzhardinge
2007-06-01 18:38   ` Christoph Lameter
2007-06-01 18:38     ` Christoph Lameter
2007-06-01 18:58     ` Jeremy Fitzhardinge
2007-06-01 18:58       ` Jeremy Fitzhardinge
2007-06-01 20:59       ` Christoph Lameter
2007-06-01 20:59         ` Christoph Lameter
2007-06-01 21:24         ` Jeremy Fitzhardinge
2007-06-01 21:24           ` Jeremy Fitzhardinge
2007-06-02 15:23       ` Dave Kleikamp
2007-06-02 15:23         ` Dave Kleikamp
2007-06-02 16:28         ` Jeremy Fitzhardinge
2007-06-02 16:28           ` Jeremy Fitzhardinge
2007-06-04  1:03           ` Dave Kleikamp
2007-06-04  1:03             ` Dave Kleikamp

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