Hi Alvin,

"A shedule request is also triggered." - This is not true because P1 has called psa_call to request a service, it's waiting for the results from the request service. Thus it's not waiting for the SLIH signal, SPM wouldn't schedule it.

Best Regards, Kevin

-----Original Message----- From: vivahavey--- via TF-M tf-m@lists.trustedfirmware.org Sent: Monday, November 21, 2022 14:08 To: tf-m@lists.trustedfirmware.org Subject: [TF-M] Interrupt SLIH Scheduling

Dear developers,

I have a question about interrupt SLIH scheduling in IPC model.

Assume that there are two secure partitions P1 and P2, and P1 has higher priority than P2. P1 calls psa_call(), so SPM blocks P1 and wakes up P2 to execute P2's service handler. Now P2 is running. Suddenly P1's interrupt occuerred, and P1's SLIH signal is asserted for more processing. A shedule request is also triggered.

Since P1 has higher priority than P2, will P2 be preemted by P1 to execute P1's SLIH immediately? If the answer is yes, the psa_call() chain will be corrupted, right?

Thanks in advance. Alvin Chang -- TF-M mailing list -- tf-m@lists.trustedfirmware.org To unsubscribe send an email to tf-m-leave@lists.trustedfirmware.org

Yes, exactly.

Best Regards, Kevin

-----Original Message----- From: Alvin Chang via TF-M tf-m@lists.trustedfirmware.org Sent: Monday, November 21, 2022 16:23 To: tf-m@lists.trustedfirmware.org Subject: [TF-M] Re: Interrupt SLIH Scheduling

Hi Kevin,

Thanks for reply! So this P1's interrupt will be pended, until the results from the request service returns and P1 invokes psa_wait() again. Am I correct? -- TF-M mailing list -- tf-m@lists.trustedfirmware.org To unsubscribe send an email to tf-m-leave@lists.trustedfirmware.org