From 1ce36bfe6424243082d3d7c2330e1a0a4ff72a43 Mon Sep 17 00:00:00 2001 From: "Daniel P. Berrange" Date: Tue, 9 May 2017 14:27:36 +0100 Subject: i386: expose "TCGTCGTCGTCG" in the 0x40000000 CPUID leaf Currently when running KVM, we expose "KVMKVMKVM\0\0\0" in the 0x40000000 CPUID leaf. Other hypervisors (VMWare, HyperV, Xen, BHyve) all do the same thing, which leaves TCG as the odd one out. The CPUID signature is used by software to detect which virtual environment they are running in and (potentially) change behaviour in certain ways. For example, systemd supports a ConditionVirtualization= setting in unit files. The virt-what command can also report the virt type it is running on Currently both these apps have to resort to custom hacks like looking for 'fw-cfg' entry in the /proc/device-tree file to identify TCG. This change thus proposes a signature "TCGTCGTCGTCG" to be reported when running under TCG. To hide this, the -cpu option tcg-cpuid=off can be used. Signed-off-by: Daniel P. Berrange Message-Id: <20170509132736.10071-3-berrange@redhat.com> Signed-off-by: Eduardo Habkost --- include/hw/i386/pc.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/hw') diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h index f48d167207..d80859bfad 100644 --- a/include/hw/i386/pc.h +++ b/include/hw/i386/pc.h @@ -379,6 +379,11 @@ bool e820_get_entry(int, uint32_t, uint64_t *, uint64_t *); #define PC_COMPAT_2_8 \ HW_COMPAT_2_8 \ + {\ + .driver = TYPE_X86_CPU,\ + .property = "tcg-cpuid",\ + .value = "off",\ + },\ {\ .driver = "kvmclock",\ .property = "x-mach-use-reliable-get-clock",\ -- cgit v1.2.3