From mboxrd@z Thu Jan 1 00:00:00 1970 From: Frank Kotler Subject: Re: Current break round up Date: Wed, 01 Oct 2008 09:43:47 -0400 Message-ID: <48E37E93.3080101@verizon.net> References: <1222802784.8421.10.camel@kirilla-desktop> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-reply-to: <1222802784.8421.10.camel@kirilla-desktop> Sender: linux-assembly-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: Kircsi Tibor Cc: linux-assembly@vger.kernel.org Kircsi Tibor wrote: > Hi, > > Sorry for my english. I started learn assembly again after 15 years. > Now, I'm learning about memory management and sys_brk system call. I've > created a really simple program, which try to extend the heap size. I've > read, when sys_brk is called with the new break address(last usable > address of the heap or data segment), it will be rounded up to the next > nearest page, but it didn't. Am I misundestand somthing? I've noticed this. Seems to be related to kernel version (2.4.33.3 here). May be a "bug"? I think you can access memory up to the top of the page (what you/we would "expect" brk to return). I don't know what to make of it. Best, Frank