Re: [PATCH 2/4] MIPS: kvm: Use vm_get_page_prot to get protection bits

From: Thomas Bogendoerfer
Date: Tue Nov 17 2020 - 05:40:43 EST


On Tue, Nov 17, 2020 at 09:18:15AM +0800, Huacai Chen wrote:
> Hi, Thomas,
>
> On Mon, Nov 16, 2020 at 8:35 PM Thomas Bogendoerfer
> <tsbogend@xxxxxxxxxxxxxxxx> wrote:
> >
> > On Sat, Nov 14, 2020 at 03:34:14PM +0800, Huacai Chen wrote:
> > > Hi, Thomas,
> > >
> > > On Fri, Nov 13, 2020 at 7:13 PM Thomas Bogendoerfer
> > > <tsbogend@xxxxxxxxxxxxxxxx> wrote:
> > > >
> > > > MIPS protection bits are setup during runtime so using defines like
> > > > PAGE_SHARED ignores this runtime changes. Using vm_get_page_prot
> > > > to get correct page protection fixes this.
> > > Is there some visible bugs if without this fix?
> >
> > no exec isn't enabled for these mappings, if cpu supports it.
> The whole series wants to set XI if supported?

that and RI where possible. I want to get rid of the PAGE_* defines,
because they lead to forgetting about RI and XI protection map setup,
which doesn't use the defines and would need another set of defines.
So by using only protection_map[] everything goes via one place.

Thomas.

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