-----Original Message----- From: Daniel P. Berrangé <berrange@redhat.com> Subject: Re: [PATCH v3 14/21] qemu: Add FakeReboot support for TDX guest
On Mon, Jun 30, 2025 at 02:17:25PM +0800, Zhenzhong Duan wrote:
Utilize the existing fake reboot mechanism to do reboot for TDX guest.
Different from normal guest, TDX guest doesn't support system_reset, so have to kill the old guest and start a new one to simulate the reboot.
Co-developed-by: Chenyi Qiang <chenyi.qiang@intel.com> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> --- src/qemu/qemu_process.c | 80 +++++++++++++++++++++++++++++++++++++++-- 1 file changed, 77 insertions(+), 3 deletions(-)
One thing I noticed during testing is that when a guest crashes during boot up eg via a triple-fault, we'll endlessly re-create QEMU which is quite expensive as memory pages are allocated/deallocated, and also burn through domain ID values.
Is it because you enabled SEPT #VE? What's your <on_crash> setting?
I'm not sure there's much (anything) we can do about these downsides though.
About the sept-ve-disable, it's a must for linux kernel, but may be not for others. Maybe checking "TD misconfiguration: SEPT #VE has to be disabled", but it's not clean code. Or maybe document it? Thanks Zhenzhong
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
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