Re: Nick's core remove PageReserved broke vmware...

[Michael S. Tsirkin]

Quoting r. Hugh Dickins <hugh@xxxxxxxxxxx>:
> Subject: Re: Nick's core remove PageReserved broke vmware...
> 
> On Mon, 14 Nov 2005, Michael S. Tsirkin wrote:
> > Quoting Gleb Natapov <gleb@xxxxxxxxxxxxx>:
> > > On Mon, Nov 14, 2005 at 02:25:35PM +0200, Michael S. Tsirkin wrote:
> > > > 
> > > > There's one thing that I have thought about: what happens
> > > > if I set DONTFORK on a page which already has COW set
> > > > (e.g. after fork)?
> > > > 
> > > > It seems that the right thing would be to force a page copy -
> > > > otherwise the page can get copied on write.
>
> > Should we worry about this?
> 
> About what?

For pages which hardware will only read, not write,
hardware driver does get_user_pages with write cleared.

This means that COW may remain set.

-- 
MST
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