Hi everyone,
As you may be aware, at Qualcomm we've been looking into various enhancements we'd like to make to Hafnium; one recent area we've identified for improvement is the fatal error handling which currently just spins on panic / abort.
To start with, we're looking at making abort() stop other CPUs and DMA, as well as introduce a platform hook to allow for platform-specific handling before propagating the error to the SPMD via FFA_ABORT; please let us know if this sound reasonable and if you have any other suggestions for improving this abort handling.
Beyond this we are also interested in improving the fatal error handling in the secure world more broadly. In particular, when a fatal event is received by TF-A then we want to give the SPMC and its SPs the opportunity to run so they can perform their own error handling before reset.
Is there a suitable framework for supporting this kind of error / reset handling? One existing mechanism for this is SDEI, though on the TF Discord it was mentioned that this has been deprecated (at least for hardware events) in favor of more recent extensions such as FEAT_NMI; would these newer extensions be suitable for software events as well? How can event handling be supported on platforms that lack these newer extensions?
Also, what would be the impact of this kind of event handling on the FF-A specification?
Thanks in advance for your support on this issue.
Regards, Jack Suann