Re: [PATCH v10 3/3] firmware: qcom_scm: Use TASK_IDLE state in wait_for_wq_completion()

[Shivendra Pratap]

On 12/3/2025 2:01 PM, Mukesh Ojha wrote:
> On Sun, Nov 30, 2025 at 08:11:04PM +0530, Shivendra Pratap wrote:
>> From: Unnathi Chalicheemala <unnathi.chalicheemala@xxxxxxxxxxxxxxxx>
>>
>> When the kernel issues an SMC (Secure Monitor Call) and the firmware
>> requests the kernel to wait, the waiting thread enters an
>> uninterruptible (D) state. In case of an extended wait request by the
>> firmware, any device suspend request, cannot proceed because of the
>> thread stuck in D state. This blocks the device suspend.
> 
> Not only that, it is stuck in D state after holding a mutex, which is
> more severe because none of the SMC calls can go through. However, this
> has been the case since the day the firmware started supporting waitq
> with a single context, which is somewhat acceptable as the firmware does
> not allow otherwise. Since, you are adding the multiple waitq context
> supported by firmware with your other patches,
> 
> Do you plan to support multiple waitq contexts i.e parallel SCM calls,
> in SCM driver as well ?

Yes. Parallel SCM can be enabled once this waitq enablement support is
in place.

thanks,
Shivendra