Re: [PATCH] x86/mm: Disable W^X detection and enforcement on 32-bit

[Guenter Roeck]

On 9/23/22 17:12, Dave Hansen wrote:
> On 9/23/22 17:09, Kirill A. Shutemov wrote:
> > On Fri, Sep 23, 2022 at 03:17:30PM -0700, Dave Hansen wrote:
> > > The 32-bit code is in a weird spot.  Some 32-bit builds (non-PAE) do not
> > > even have NX support.  Even PAE builds that support NX have to contend
> > > with things like EFI data and code mixed in the same pages where W+X
> > > is unavoidable.
> > >
> > > The folks still running X86_32=y kernels are unlikely to care much about
> > > NX.  That combined with the fundamental inability fix _all_ of the W+X
> > > things means this code had little value on X86_32=y.  Disable the checks.
> > Maybe downgrade the check to a warning for X86_32=y?
>
> But for this EFI case, we really don't want the warning.  It's unfixable.
>
> I'm also not sure we want to go to the trouble to properly silence the
> warning in these unfixable cases.  There was an argument elsewhere in
> the thread that we really shouldn't be warning on things that we don't
> have full intentions to fix.  I buy that argument.

Yes, there are already way too many such useless warnings around.
Please don't add more of them.

Guenter