On Fri, Jan 12, 2024 at 09:20:19AM +0000, Duan, Zhenzhong wrote:
-----Original Message----- From: Daniel P. Berrangé <berrange@redhat.com> Subject: Re: [PATCH rfcv3 07/11] qemu: add hard reboot in QEMU driver
On Mon, Nov 27, 2023 at 04:55:17PM +0800, Zhenzhong Duan wrote:
From: Chenyi Qiang <chenyi.qiang@intel.com>
Add the new flag VIR_DOMAIN_REBOOT_HARD/VIR_DOMAIN_SHUTDOWN_HARD to carry out a hard reboot, which kills the QEMU process and creates a new one with the same definition.
AFAICT, the _HARD flags cause it to issue a QEMU monitor command todo an ACPI shutdown and then re-create QEMU.
IOW, it seems like this is just the same as the existing _ACPI flags, and so I'm not sure why we need any new functionality at all.
What is the existing ACPI shutdown & fake reboot not able to achieve ?
ACPI shutdown & fake reboot send below QMP command in sequence:
"system_powerdown", "system_reset", "cont".
"system_reset" QMP command isn't supported by TDX for security reasons. So we have to kill old QEMU and re-create new one.
We are still doing the 'system_powerdown' step first though, to do a graceful shutdown, before re-creating QEMU, and the powerdown is what we refer to as "ACPI". So I think we don't need new public API constants. We should still use the _ACPI flag, and just "do the right thing" with choosing between system_reset vs re-creating QEMU depending on whether TDX/SEV are active. That way the public API user experience is unchanged, only the internal impl varies. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|