Re: Current break round up

"Tibor Kircsi" <[email protected]> Wed, 1 Oct 2008 16:40:42 +0200
Newsgroups org.kernel.vger.linux-assembly
Message-ID <[email protected]>
Hi,

You're right! I tested it and I could write and read above the current
break after I call brk. I'll will test the page border too. Thanks.

regards,
Tibor

On Wed, Oct 1, 2008 at 3:43 PM, Frank Kotler <[email protected]> wrote:
>
> 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
>