Hi Enric,
On Thu, Apr 30, 2020 at 8:26 AM Enric Balletbo i Serra
<enric.balle...@collabora.com> wrote:
>
> Hi Prashant,
>
> On 30/4/20 2:43, Prashant Malani wrote:
> > On Wed, Apr 29, 2020 at 5:38 PM Daniil Lunev <dlu...@chromium.org> wrote:
> >>
> >> [to make it appear on the mailing list as I didn't realize I was in
> >> hypertext sending mode]
> >>
> >> On Thu, Apr 30, 2020 at 10:11 AM Daniil Lunev <dlu...@chromium.org> wrote:
> >>>
> >>> Hi Enric.
> >>> I encountered the issue on a Hatch device when trying running 5.4 kernel
> >>> on that. After talking to Prashant it seems that any device with coreboot
> >>> built before a certain point (a particular fix for device hierarchy in
> >>> ACPI tables of Chrome devices which happened in mid-April) will not be
> >>> able to correctly initialize the driver and will get a kernel panic
> >>> trying to do so.
> >
> > A clarifying detail here: This should not be seen in any current
> > *production* device. No prod device firmware will carry the erroneous
> > ACPI device entry.
> >
>
> Thanks for the clarification. Then, I don't think we need to upstream this.
> This
> kind of "defensive-programming" it's not something that should matter to
> upstream.
Actually, on second thought, I am not 100% sure about this:
Daniil, is the erroneous ACPI device on a *production* firmware for
this device (I'm not sure about the vintage of that device's BIOS)?
My apologies for the confusion, Enric and Daniil; but would be good to
get clarification from Daniil.
Best regards,
>
> Thanks,
> Enric
>
>
> >>> Thanks,
> >>> Daniil
> >>>
> >>> On Thu, Apr 30, 2020 at 7:58 AM Enric Balletbo i Serra
> >>> <enric.balle...@collabora.com> wrote:
> >>>>
> >>>> Hi Daniil,
> >>>>
> >>>> Thank you for the patch.
> >>>>
> >>>> On 28/4/20 3:02, Daniil Lunev wrote:
> >>>>> Missing EC in device hierarchy causes NULL pointer to be returned to the
> >>>>> probe function which leads to NULL pointer dereference when trying to
> >>>>> send a command to the EC. This can be the case if the device is missing
> >>>>> or incorrectly configured in the firmware blob. Even if the situation
> >>>>
> >>>> There is any production device with a buggy firmware outside? Or this is
> >>>> just
> >>>> for defensive programming while developing the firmware? Which device is
> >>>> affected for this issue?
> >>>>
> >>>> Thanks,
> >>>> Enric
> >>>>
> >>>>> occures, the driver shall not cause a kernel panic as the condition is
> >>>>> not critical for the system functions.
> >>>>>
> >>>>> Signed-off-by: Daniil Lunev <dlu...@chromium.org>
> >>>>> ---
> >>>>>
> >>>>> drivers/platform/chrome/cros_ec_typec.c | 5 +++++
> >>>>> 1 file changed, 5 insertions(+)
> >>>>>
> >>>>> diff --git a/drivers/platform/chrome/cros_ec_typec.c
> >>>>> b/drivers/platform/chrome/cros_ec_typec.c
> >>>>> index 874269c07073..30d99c930445 100644
> >>>>> --- a/drivers/platform/chrome/cros_ec_typec.c
> >>>>> +++ b/drivers/platform/chrome/cros_ec_typec.c
> >>>>> @@ -301,6 +301,11 @@ static int cros_typec_probe(struct platform_device
> >>>>> *pdev)
> >>>>>
> >>>>> typec->dev = dev;
> >>>>> typec->ec = dev_get_drvdata(pdev->dev.parent);
> >>>>> + if (!typec->ec) {
> >>>>> + dev_err(dev, "Failed to get Cros EC data\n");
> >>>>> + return -EINVAL;
> >>>>> + }
> >>>>> +
> >>>>> platform_set_drvdata(pdev, typec);
> >>>>>
> >>>>> ret = cros_typec_get_cmd_version(typec);
> >>>>>
