From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gerd Hoffmann <kraxel@redhat.com>
Subject: Re: mini-os: sbrk() doesn't allocate pages?
Date: Thu, 14 Aug 2008 10:42:04 +0200
Message-ID: <48A3EFDC.5090403@redhat.com>
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Gerd Hoffmann wrote:
>   Hi,
> 
> I'm wondering how the mini-os heap allocater work.  The sbrk() function
> in mm.c seems to *not* allocate pages for the heap.  Instead it uses the
> zero page and maps it into the heap space when a new page is needed ...
> 
> I can't believe is is supposed to work that way.  Is that a bug?  Did I
> miss some logic somewhere in the code?

Oh, cow in the pagefault handler, that is the missing bit ...

cheers,
  Gerd


-- 
http://kraxel.fedorapeople.org/xenner/