qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Qemu-devel] [PATCH] target-i386: Enable "check" mode by default


From: Eduardo Habkost
Subject: [Qemu-devel] [PATCH] target-i386: Enable "check" mode by default
Date: Wed, 26 Aug 2015 13:50:25 -0300

Current default behavior of QEMU is to silently disable features that
are not supported by the host when a CPU model is requested in the
command-line. This means that in addition to risking breaking guest ABI
by default, we are silent about it.

I would like to enable "enforce" by default, but this can easily break
existing production systems because of the way libvirt makes assumptions
about CPU models today (this will change in the future, once QEMU
provide a proper interface for checking if a CPU model is runnable).

But there's no reason we should be silent about it. So, change
target-i386 to enable "check" mode by default so at least we have some
warning printed to stderr (and hopefully logged somewhere) when QEMU
disables a feature that is not supported by the host system.

Signed-off-by: Eduardo Habkost <address@hidden>
---
 target-i386/cpu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index cfb8aa7..32fee00 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -3121,7 +3121,7 @@ static Property x86_cpu_properties[] = {
     DEFINE_PROP_BOOL("hv-relaxed", X86CPU, hyperv_relaxed_timing, false),
     DEFINE_PROP_BOOL("hv-vapic", X86CPU, hyperv_vapic, false),
     DEFINE_PROP_BOOL("hv-time", X86CPU, hyperv_time, false),
-    DEFINE_PROP_BOOL("check", X86CPU, check_cpuid, false),
+    DEFINE_PROP_BOOL("check", X86CPU, check_cpuid, true),
     DEFINE_PROP_BOOL("enforce", X86CPU, enforce_cpuid, false),
     DEFINE_PROP_BOOL("kvm", X86CPU, expose_kvm, true),
     DEFINE_PROP_UINT32("level", X86CPU, env.cpuid_level, 0),
-- 
2.1.0




reply via email to

[Prev in Thread] Current Thread [Next in Thread]