Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20230628085253.1013799-1-koba.ko@canonical.com> <SJ1PR11MB608340E81A15F20EBAD75F08FC24A@SJ1PR11MB6083.namprd11.prod.outlook.com>
In-Reply-To: <SJ1PR11MB608340E81A15F20EBAD75F08FC24A@SJ1PR11MB6083.namprd11.prod.outlook.com>
From:   Koba Ko <koba.ko@canonical.com>
Date:   Thu, 29 Jun 2023 11:52:33 +0800
Message-ID: <CAJB-X+U7Af3ypru3O0quGTqrsJPMO3b7uoBTNjTLSixrmrvXJw@mail.gmail.com>
Subject: Re: [PATCH] EDAC/i10nm: shift exponent is negative
To:     "Luck, Tony" <tony.luck@intel.com>
Cc:     Borislav Petkov <bp@alien8.de>, James Morse <james.morse@arm.com>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Robert Richter <rric@kernel.org>,
        "linux-edac@vger.kernel.org" <linux-edac@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

hi Luck,
I agree with your points
is it expected to shift with negative?

Thanks
Koba Ko

On Thu, Jun 29, 2023 at 12:41=E2=80=AFAM Luck, Tony <tony.luck@intel.com> w=
rote:
>
> >       ranks =3D numrank(mtr);
> >       rows =3D numrow(mtr);
> >       cols =3D imc->hbm_mc ? 6 : numcol(mtr);
> > +     if (ranks =3D=3D -EINVAL || rows =3D=3D -EINVAL || cols =3D=3D -E=
INVAL)
> > +             return 0;
>
> This seems to be just hiding the real problem that a DIMM was found
> with some number of ranks, rows, or columns that the EDAC driver
> didn't expect to see. Your fix makes the driver skip over this DIMM.
>
> Can you build your kernel with CONFIG_EDAC_DEBUG=3Dy and see
> what messages you get from this code:
>
> static int skx_get_dimm_attr(u32 reg, int lobit, int hibit, int add,
>                              int minval, int maxval, const char *name)
> {
>         u32 val =3D GET_BITFIELD(reg, lobit, hibit);
>
>         if (val < minval || val > maxval) {
>                 edac_dbg(2, "bad %s =3D %d (raw=3D0x%x)\n", name, val, re=
g);
>                 return -EINVAL;
>         }
>
> -Tony
>
>