Re: [PATCH v4] mmc: Avoid reprogram all keys to Inline Crypto Engine for MMC runtime suspend resume

[Neeraj Soni <neeraj.soni@oss.qualcomm.com>]

Hello Ulf,

Can you please help to clarify? If there is no more modifications expected
then wanted to understand when this patch can be picked for mmc-next.

Regards
Neeraj

On 5/14/2026 11:26 AM, Neeraj Soni wrote:
> 
> 
> On 1/22/2026 3:44 PM, Ulf Hansson wrote:
>> On Thu, 22 Jan 2026 at 02:14, Eric Biggers <ebiggers@kernel.org> wrote:
>>>
>>> On Wed, Jan 21, 2026 at 03:12:43PM +0100, Ulf Hansson wrote:
>>>>> diff --git a/drivers/mmc/core/crypto.c b/drivers/mmc/core/crypto.c
>>>>> index fec4fbf16a5b..a5a90bfc634e 100644
>>>>> --- a/drivers/mmc/core/crypto.c
>>>>> +++ b/drivers/mmc/core/crypto.c
>>>>> @@ -15,7 +15,7 @@
>>>>>  void mmc_crypto_set_initial_state(struct mmc_host *host)
>>>>>  {
>>>>>         /* Reset might clear all keys, so reprogram all the keys. */
>>>>> -       if (host->caps2 & MMC_CAP2_CRYPTO)
>>>>> +       if ((host->caps2 & MMC_CAP2_CRYPTO) && !(host->caps2 & MMC_CAP2_CRYPTO_NO_REPROG))
>>>>>                 blk_crypto_reprogram_all_keys(&host->crypto_profile);
>>>>
>>>> As far as I understand, calling blk_crypto_reprogram_all_keys() would
>>>> only be needed for those mmc hosts that lose their corresponding ICE
>>>> context during runtime+system suspend, reset and possibly during
>>>> ->probe().
>>>>
>>>> In other words, calling mmc_crypto_set_initial_state() from
>>>> mmc_set_initial_state() looks like it's a mistake, as it has really
>>>> nothing to do with the card's initialization, unless I have understood
>>>> this wrong!?
>>>>
>>>> That said, I would rather make the mtk-sd and sdhci-msm drivers to
>>>> handle this themselves, by explicitly calling
>>>> blk_crypto_reprogram_all_keys() when needed - and drop
>>>> mmc_crypto_set_initial_state() altogether.
>>>>
>>>> For the sdhci-msm case, it seems like the only case we need to care
>>>> about is for the reset.
>>>>
>>>> For mtk-sd I don't know what is needed, but possibly Eric can help out here?
>>>
>>> The comment for mmc_set_initial_state() says "Set initial state after a
>>> power cycle or a hw_reset."  I relied on that when I added the call to
>>> mmc_crypto_set_initial_state() back in 2020.  In the following thread it
>>> was also discussed that the code was intended to reprogram the keys on
>>> reset, not runtime suspend as that shouldn't be needed:
>>> https://lore.kernel.org/linux-mmc/X7gQ9Y44iIgkiM64@sol.localdomain/T/#u
>>
>> The comment in the mmc_set_initial_state() is referring to the card
>> and not the host controller. There have been some similar
>> misunderstandings in the past for other functions in the core, sorry.
>>
>> In any case, I have been trying to understand where the ICE context
>> really belongs and recently Neeraj answered that question [1].
>>
>>>
>>> If that is not what it actually does, it probably would be appropriate
>>> to replace it with something else.
>>
>> I agree, the comment(s) could deserve some clarifications.
> 
> Hello Ulf. Do you expect modifications in the comment for mmc_set_initial_state()?
> I am sorry i did not follow up and assumed that no more changes are expected in
> the patch but i stil see it is not yet reviewed or approved.
>>
>>>
>>> - Eric
>>
>> Kind regards
>> Uffe
>>
>> [1]
>> https://lore.kernel.org/all/e1f689d0-523b-5842-3a6e-10b431d617ce@oss.qualcomm.com/
>>
> 
> Regards,
> Neeraj
>