Re: [PATCH] tpm: Switch to platform_get_irq_optional()

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 24-10-2019 16:25, Jarkko Sakkinen wrote:
> On Wed, Oct 23, 2019 at 04:32:57PM +0200, Hans de Goede wrote:
>> Hi,
>>
>> On 23-10-2019 13:37, Jarkko Sakkinen wrote:
>>> On Mon, Oct 21, 2019 at 05:56:56PM +0200, Hans de Goede wrote:
>>>> Hi,
>>>>
>>>> On 21-10-2019 17:49, Jarkko Sakkinen wrote:
>>>>> On Sat, Oct 19, 2019 at 11:45:28AM +0200, Hans de Goede wrote:
>>>>>> Since commit 7723f4c5ecdb ("driver core: platform: Add an error message to
>>>>>> platform_get_irq*()"), platform_get_irq() will call dev_err() on an error,
>>>>>> as the IRQ usage in the tpm_tis driver is optional, this is undesirable.
>>>>>>
>>>>>> Specifically this leads to this new false-positive error being logged:
>>>>>> [    5.135413] tpm_tis MSFT0101:00: IRQ index 0 not found
>>>>>>
>>>>>> This commit switches to platform_get_irq_optional(), which does not log
>>>>>> an error, fixing this.
>>>>>>
>>>>>> Cc: <stable@vger.kernel.org> # 5.4.x
>>>>>
>>>>> Incorrect format (should be wo '<' and '>').
>>>>
>>>> According to:
>>>>
>>>> https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
>>>>
>>>> the '<' and '>' should be added when adding a # <kerner>
>>>
>>> OK, right so it was. This first patch that I'm reviewing with such
>>> commit.
>>>
>>>>> Also, not sure why this should be backported to stable kernel anyway.
>>>>
>>>> Because false-positive error messages are bad and cause users to
>>>> file false-positive bug-reports.
>>>
>>> Neither categorizes into a regression albeit being unfortunate
>>> glitches.
>>
>> The stable series also does other small fixes, such as adding new
>> pci/usb-ids, etc. This clearly falls within this. IMHO ideally this
>> should go to a 5.4-rc# making the whole discussion moot, but since
>> I was afraid it would not make 5.4, I added the Cc: stable.
> 
> I get adding PCI/USB id as it extends the hardware support for the
> stable kernel without risking its stability. This patch is factors
> less useful.

It also has about 0% chance of causing regressions and it does
help to avoid false--positive bug reports.

TBH I'm quite surprised we are even having this discussion...

Regards,

Hans