Re: [v5 PATCH] RISC-V: Fix unsupported isa string info.

From: Atish Patra
Date: Sat Sep 14 2019 - 00:07:59 EST


On Fri, 2019-09-13 at 13:47 -0700, Palmer Dabbelt wrote:
> On Mon, 09 Sep 2019 23:00:10 PDT (-0700), Christoph Hellwig wrote:
> > On Fri, Sep 06, 2019 at 11:27:57PM +0000, Atish Patra wrote:
> > > > Agreed. May be something like this ?
> > > >
> > > > Let's say f/d is enabled in kernel but cpu doesn't support it.
> > > > "unsupported isa" will only appear if there are any unsupported
> > > > isa.
> > > >
> > > > processor : 3
> > > > hart : 4
> > > > isa : rv64imac
> > > > unsupported isa : fd
> > > > mmu : sv39
> > > > uarch : sifive,u54-mc
> > > >
> > > > May be I am just trying over optimize one corner case :) :).
> > > > /proc/cpuinfo should just print all the isa string. That's it.
> > > >
> > >
> > > Ping ?
> >
> > Yes, I agree with the "dumb" reporting of all capabilities.
>
> I agree: it looks like other architectures are passing info (ie, x86
> flags)
> that isn't supported by userspace. We have the ELF hwcap stuff for
> those who
> want to tell which instructions they can run, so it's sane to just
> keep this
> simple.

Great. That will simplify the code path as well. I will send a v6 with
the fixes.

--
Regards,
Atish