Re: Re : vm: weird behaviour when munmapping

From: Francis Moreau
Date: Tue Nov 21 2006 - 03:43:28 EST


On 11/20/06, Hugh Dickins <hugh@xxxxxxxxxxx> wrote:
On Mon, 20 Nov 2006, Francis Moreau wrote:
>
> I end up to see "open(B), close(B)" sequence when unmapping a part of
> the dumb device that I found strange. I think that "open(A') close(B)"
> can give more information to the driver and reflect that B is unmapped
> and A' is still mapped and becomes the new mapped area.
> But it's may be just me...

I think I do now get your point. But your way round doesn't really

my fault, I think I wasn't very clear when explaining myself

reflect what's going on either: the range A' was already open and now
you open it again. Until there's some driver actually needing more
sophisticated treatment, let's just leave it the simple way it is.

Yes, I agree that both ways are not satisfacting. Maybe having
vma->resize() method would have been better, I dunno.

Anyways thanks for your answers.
--
Francis
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