Re: [BUG] get_unmapped_area() change -> non booting machine

[Martin J. Bligh]

--On Sunday, February 15, 2004 06:25:44 +0100 Andi Kleen <ak@xxxxxxx> wrote:

> On Fri, 13 Feb 2004 03:26:04 +0000
> Jamie Lokier <jamie@xxxxxxxxxxxxx> wrote:
> 
>> Linus Torvalds wrote:
>> > One option is to mark the brk() VMA's as being grow-up (which they are), 
>> > and make get_unmapped_area() realize that it should avoid trying to 
>> > allocate just above grow-up segments or just below grow-down segments. 
>> > That's still something of a special case, but at least it's not "magic" 
>> > any more, now it's more of a "makes sense".
>> 
>> That reminds me.  What happens when grow-down stack VMAs finally bump
>> into another VMA.  Is there an unmapped guard page retained to segfault
>> the program, or does the program silently start overwriting the VMA it
>> bumped into?
> 
> In the standard kernel it silently overwrites, but in 2.4-aa there was a patch forever
> that adds a guard page.

Do you happen to remember the name of the patch? Hunting in Andrea's tree
isn't always easy ;-)

M.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/