Re: RE: [PATCH v1] rtc: cmos: avoid UIP when writing/reading alarm time

[Sasha Levin <sashal@kernel.org>]

On Thu, Dec 08, 2022 at 10:47:17PM +0100, Mateusz Jończyk wrote:
>W dniu 7.12.2022 o 07:51, Chen, Kane pisze:
>>> -----Original Message-----
>>> From: Sasha Levin <sashal@kernel.org>
>>> Sent: Wednesday, December 7, 2022 1:13 PM
>>> To: Chen, Kane <kane.chen@intel.com>
>>> Cc: stable@vger.kernel.org
>>> Subject: Re: [PATCH v1] rtc: cmos: avoid UIP when writing/reading alarm time
>>>
>>> On Wed, Dec 07, 2022 at 11:57:22AM +0800, Kane Chen wrote:
>>>> While runnings s0ix cycling test based on rtc alarm wakeup on ADL-P
>>>> devices, We found the data from CMOS_READ is not reasonable and causes
>>> RTC wake up fail.
>>>> With the below changes, we don't see unreasonable data from cmos and
>>> issue is gone.
>>>
>>> Thanks for the analysis, I can queue most of these up. There are two which
>>> won't go in:
>>>
>>>> cd17420: rtc: cmos: avoid UIP when writing alarm time
>>>> cdedc45: rtc: cmos: avoid UIP when reading alarm time
>>>> ec5895c: rtc: mc146818-lib: extract mc146818_avoid_UIP
>>>> ea6fa49: rtc: mc146818-lib: fix RTC presence check
>>>> 13be2ef: rtc: cmos: Disable irq around direct invocation of
>>>> cmos_interrupt()
>>>> 0dd8d6c: rtc: Check return value from mc146818_get_time()
>>>> e1aba37: rtc: cmos: remove stale REVISIT comments
>>>> 6950d04: rtc: cmos: Replace spin_lock_irqsave with spin_lock in hard
>>>> IRQ
>>> This one fixes a commit which isn't in the 5.10 tree.
>>>
>>>> d35786b: rtc: mc146818-lib: change return values of mc146818_get_time()
>>>> ebb22a0: rtc: mc146818: Dont test for bit 0-5 in Register D
>>>> 211e5db: rtc: mc146818: Detect and handle broken RTCs
>>>> dcf257e: rtc: mc146818: Reduce spinlock section in mc146818_set_time()
>>> This one looks like an optimization.
>>>
>>> --
>> I'm sorry,
>> I thought dcf257e and  6950d04, 13be2ef  are also required to avoid cherry-pick conflict
>> After checking again, dcf257e, 6950d04, 13be2ef are not needed.
>>
>> Here is the list I would like to pick
>> cd17420: rtc: cmos: avoid UIP when writing alarm time
>> cdedc45: rtc: cmos: avoid UIP when reading alarm time
>> ec5895c: rtc: mc146818-lib: extract mc146818_avoid_UIP
>> ea6fa49: rtc: mc146818-lib: fix RTC presence check
>> 0dd8d6c: rtc: Check return value from mc146818_get_time()
>> e1aba37: rtc: cmos: remove stale REVISIT comments
>> d35786b: rtc: mc146818-lib: change return values of mc146818_get_time()
>> ebb22a0: rtc: mc146818: Dont test for bit 0-5 in Register D
>> 211e5db: rtc: mc146818: Detect and handle broken RTCs
>> 05a0302: rtc: mc146818: Prevent reading garbage
>>
>> Thanks a lot
>>
>>> Thanks,
>>> Sasha
>>>
>Hello,
>
>I think that you should also pick these patches which fix issues in the series
>that is prepared for 5.4:
>
>1) commit 7372971c1be5 ("rtc: mc146818-lib: fix signedness bug in mc146818_get_time()")
>
>which fixes d35786b: rtc: mc146818-lib: change return values of mc146818_get_time()
>
>2) commit 13be2efc390a ("rtc: cmos: Disable irq around direct invocation of cmos_interrupt()")
>
>which fixes 6950d04: rtc: cmos: Replace spin_lock_irqsave with spin_lock in hard IRQ
>and is not prepared for 5.4 stable even though it was mentioned above.
>
>3) commit 811f5559270f ("rtc: mc146818-lib: fix locking in mc146818_set_time")
>
>which fixes dcf257e: rtc: mc146818: Reduce spinlock section in mc146818_set_time()

Ack, will do, thanks.

-- 
Thanks,
Sasha