Messages in this thread | | | Date | Wed, 24 Sep 2008 21:54:36 -0700 | From | "H. Peter Anvin" <> | Subject | Re: [PATCH 1/2] VMware guest detection for x86 and x86-64 |
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Greg KH wrote: > > Well, having a config option like this isn't the way to go as it will be > forced on for all distros and users anyway. > > A simple cpuid test is the easier way to do this, that's what the > userspace tools do, if it's really needed in the kernel. But hopefully, > such things shouldn't be needed within the kernel as it's not Linux's > fault that the hypervisor has bugs in it :) > > We wouldn't be wanting to work around bugs in Microsoft's hypervisor, > would we? >
We pretty much have to, just as we have to work around bugs in, say, AMD's microcode. We have avoided it so far, but it's gotten to a breaking point, and rather than having ad hoc hacks scattered all over the place I want a centralized test site setting a single global variable.
Unfortunately, hypervisor vendors haven't adopted a uniform detection scheme (CPUID level 0x40000000 is sometimes mentioned as a pseudo-standard, but it's not universal, and not all virtualization solutions even can override CPUID.)
-hpa
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