On 12.10.21 13:57, Zheng Chuan wrote: > Hi all, > > After reading the code of jailhouse, I have a few questions. > 1.Once Jailhouse is activated, the boot Linux will run as a VM. If it is > possible to run VM by KVM(nested mode) in the root cell? >
Nope, but you can find traces of an attempt in https://github.com/siemens/jailhouse/commits/wip/kvm > 2.I wonder why the root cell need to runs in guest mode? Whether jailhouse > can run root cell in host mode, create KVM VM inside > root cell. So jailhouse can support both partition and VM. Two main reasons: - security/safety: If you leave the root Linux running in host mode, it becomes part of the trusted code base, increasing it by a "few" orders of magnitude - functionality: only by intercepting certain I/O accesses, Jailhouse is able to emulate the ivshmem devices > > 3.When create a non-root cell, the jailhouse driver executes cpu_down() to > offline CPUs, but the offline CPU seems to be running > and respond to interruptions. And the hypervisor seems to have done nothing > to wake up the CPUs(assigned to non-root cell), > or did I miss the important part of the code? The offlined and then "stolen" CPUs of the non-root cell are first parked and then finally started again at (amost) architectural reset state when doing "jailhouse cell start". On x86, you can see the SIPIs being injected for that in the Jailhouse log. Jan -- Siemens AG, T RDA IOT Corporate Competence Center Embedded Linux -- You received this message because you are subscribed to the Google Groups "Jailhouse" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/jailhouse-dev/58cd66eb-1988-cef4-09bc-2438f790f7f8%40siemens.com.
