Question about handle_host_interrupt processing and the role of r10 #74
Description
Hello Jonomango,
I'm currently trying to understand the host_interrupts handling within this VT-based debugger. I have a few questions regarding the handle_host_interrupt function and the usage of the r10 register within this context.
Specifically, I'm trying to trace the flow of host-generated interrupts (NMIs and other exceptions) and how they are managed before potentially being injected into the guest.
Here are my specific points of confusion:
Processing of Host Interrupts: Could you please provide a high-level overview of how the handle_host_interrupt function processes different types of host interrupts (e.g., NMIs vs. other exceptions)? What are the key steps involved in handling these interrupts?
Role of r10 Register: In the default case of the switch statement within handle_host_interrupt, the value of frame->r10 is assigned to frame->rip with the comment "// jump to the exception handler". I haven't been able to find where r10 is initially set to this exception handler address. Could you please clarify the origin and intended purpose of the r10 register in this function? Is it part of a specific calling convention, or is it set elsewhere in the codebase?
Interrupt Injection to Guest: Following the processing in handle_host_interrupt, how are the host-originated interrupts (or information about them) eventually injected into the guest VM, if that's the intended behavior? I'm particularly interested in the path from handle_host_interrupt to the point where the guest vCPU receives a virtual interrupt.
Understanding these aspects would greatly help me in my current investigation of the debugger's low-level interrupt handling mechanisms.
Thank you for your time and assistance.