Re: [PATCH 0/2] mm: introduce MAP_FIXED_SAFE

[Florian Weimer]

On 12/06/2017 09:06 AM, John Hubbard wrote:
> On 12/05/2017 11:35 PM, Florian Weimer wrote:
> > On 12/06/2017 08:33 AM, John Hubbard wrote:
> > > In that case, maybe:
> > >
> > >  ÂÂÂÂ MAP_EXACT
> > >
> > > ? ...because that's the characteristic behavior.
> >
> > Is that true? mmap still silently rounding up the length to the page size, I assume, so even that name is misleading.
>
> Hi Florian,
>
> Not as far as I can tell, it's not doing that.
>
> For both MAP_FIXED, and this new flag, the documented (and actual)
> behavior is *not* to do any such rounding. Instead, the requested
> input address is required to be page-aligned itself, and mmap()
> should be honoring the exact addr.

I meant the length, not the address.

Florian