On Mon, 20 May 2013, Alexey Suslikov wrote: > Seen in dmesg, HV flag will indicate operating system is run under > hypervisor and weird things are possible while running kernel code which > depends on CPU features. > > After all, it is kinda documented by AMD on page 570 of > http://support.amd.com/us/Processor_TechDocs/24594_APM_v3.pdf > > (AMD named it RAZ, but I put meaningful name like in FreeBSD - should we > put a reference to above mentioned document near the define?).
AMD did not name it "RAZ". "RAZ" stands for "read as zero", a condition that is true off many bits in the flags register, etc. Calling it RAZ would be like saying that the street I live on is named "One Way Street". The fact that neither AMD or Intel give a real definition for this makes it sound like KVM squatted on the bit without actually getting a real reservation for it. (In general, when Intel and AMD disagree about the name of a CPUID bit, we prefer the name given by Intel.) Philip