Re: [PATCH v1] tpm_crb: Check ACPI_COMPANION() against NULL during probe

[Jarkko Sakkinen <jarkko@kernel.org>]

On Mon, Jun 08, 2026 at 07:35:26PM +0200, Rafael J. Wysocki wrote:
> On Tue, May 19, 2026 at 11:01 PM Rafael J. Wysocki <rafael@kernel.org> wrote:
> >
> > On Sat, May 16, 2026 at 3:15 AM Jarkko Sakkinen <jarkko@kernel.org> wrote:
> > >
> > > On Tue, May 12, 2026 at 06:16:23PM +0200, Rafael J. Wysocki wrote:
> > > > From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
> > > >
> > > > Every platform driver can be forced to match a device that doesn't match
> > > > its list of device IDs because of device_match_driver_override(), so
> > > > platform drivers that rely on the existence of a device's ACPI companion
> > > > object need to verify its presence.
> > > >
> > > > Accordingly, add a requisite ACPI_COMPANION() check against NULL to the
> > > > tpm_crb driver.
> > > >
> > > > Fixes: 48fe2cddc85c ("tpm_crb: Convert ACPI driver to a platform one")
> > > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> > > > ---
> > > >  drivers/char/tpm/tpm_crb.c |    6 +++++-
> > > >  1 file changed, 5 insertions(+), 1 deletion(-)
> > > >
> > > > --- a/drivers/char/tpm/tpm_crb.c
> > > > +++ b/drivers/char/tpm/tpm_crb.c
> > > > @@ -786,8 +786,8 @@ static int crb_map_pluton(struct device
> > > >  static int crb_acpi_probe(struct platform_device *pdev)
> > > >  {
> > > >       struct device *dev = &pdev->dev;
> > > > -     struct acpi_device *device = ACPI_COMPANION(dev);
> > > >       struct acpi_table_tpm2 *buf;
> > > > +     struct acpi_device *device;
> > > >       struct crb_priv *priv;
> > > >       struct tpm_chip *chip;
> > > >       struct tpm2_crb_smc *crb_smc;
> > > > @@ -797,6 +797,10 @@ static int crb_acpi_probe(struct platfor
> > > >       u32 sm;
> > > >       int rc;
> > > >
> > > > +     device = ACPI_COMPANION(dev);
> > > > +     if (!device)
> > > > +             return -ENODEV;
> > > > +
> > > >       status = acpi_get_table(ACPI_SIG_TPM2, 1,
> > > >                               (struct acpi_table_header **) &buf);
> > > >       if (ACPI_FAILURE(status) || buf->header.length < sizeof(*buf)) {
> > > >
> > > >
> > > >
> > >
> > > Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
> >
> > Thanks!
> >
> > So do you want me to pick up this one?
> 
> I took the silence as consent and picked it up.  If you'd rather route
> it differently, please let me know.

OK my bad in commes, sorry. I did already pick this up and it is
going to my next PR. 

> 
> Thanks!

BR, Jarkko