systems with VT-x/EPT (e.g. Sandybridge Macbooks). This will most
likely work on VMWare Workstation8/Player4 as well. See the VMWare app
note at:
http://communities.vmware.com/docs/DOC-8970
Fusion doesn't propagate the PAT MSR auto save-restore entry/exit
control bits. Deal with this by noting that fact and setting up the
PAT MSR to essentially be a no-op - it is init'd to power-on default,
and a software shadow copy maintained.
Since it is treated as a no-op, o/s settings are essentially ignored.
This may not give correct results, but since the hypervisor is running
nested, a number of bets are already off.
On a quad-core/HT-enabled 'MacBook8,2', nested VMs with 1/2/4 vCPUs were
fired up. The more nested vCPUs the worse the performance, unless the VMs
were started up in multiplexed mode where things worked perfectly up to
the limit of 8 vCPUs.
Reviewed by: neel
- Don't always pass the cpuid request to the current CPU as some nodes
we will emulate purely in software.
- Pass in the APIC ID of the virtual CPU so we can return the proper APIC
ID.
- Always report a completely flat topology with no SMT or multicore.
- Report the CPUID2_HV feature and implement support for the 0x40000000
CPUID level.
- Use existing constants from <machine/specialreg.h> when possible and
use cpu_feature2 when checking for VMX support.
There was an assumption by the "callers" of this macro that on "return" the
%rsp will be pointing to the 'vmxctx'. The macro was not doing this and thus
when trying to restore host state on an error from "vmlaunch" or "vmresume"
we were treating the memory locations on the host stack as 'struct vmxctx'.
This led to all sorts of weird bugs like double faults or invalid instruction
faults.
This bug is exposed by the -O2 option used to compile the kernel module. With
the -O2 flag the compiler will optimize the following piece of code:
int loopstart = 1;
...
if (loopstart) {
loopstart = 0;
vmx_launch();
} else
vmx_resume();
into this:
vmx_launch();
Since vmx_launch() and vmx_resume() are declared to be __dead2 functions the
compiler is free to do this. The compiler has no way to know that the
functions return indirectly through vmx_setjmp(). This optimization in turn
leads us to trigger the bug in VMXCTX_GUEST_RESTORE().
With this change we can boot a 8.1 guest on a 9.0 host.
Reported by: jhb@
This was benign because the interruption info field is a 32-bit quantity and
the hardware guarantees that the upper 32-bits are all zeros. But it did make
reading the objdump output very confusing.
run as a 1/2 CPU guest on an 8.1 bhyve host.
bhyve/inout.c
inout.h
fbsdrun.c
- Rather than exiting on accesses to unhandled i/o ports, emulate
hardware by returning -1 on reads and ignoring writes to unhandled
ports. Support the previous mode by allowing a 'strict' parameter
to be set from the command line.
The 8.1 guest kernel was vastly cut down from GENERIC and had no
ISA devices. Booting GENERIC exposes a massive amount of random
touching of i/o ports (hello syscons/vga/atkbdc).
bhyve/consport.c
dev/bvm/bvm_console.c
- implement a simplistic signature for the bvm console by returning
'bv' for an inw on the port. Also, set the priority of the console
to CN_REMOTE if the signature was returned. This works better in
an environment where multiple consoles are in the kernel (hello syscons)
bhyve/rtc.c
- return 0 for the access to RTC_EQUIPMENT (yes, you syscons)
amd64/vmm/x86.c
x86.h
- hide a bunch more CPUID leaf 1 bits from the guest to prevent
cpufreq drivers from probing.
The next step will be to move CPUID handling completely into
user-space. This will allow the full spectrum of changes from
presenting a lowest-common-denominator CPU type/feature set, to
exposing (almost) everything that the host can support.
Reviewed by: neel
Obtained from: NetApp
vmm.ko - kernel module for VT-x, VT-d and hypervisor control
bhyve - user-space sequencer and i/o emulation
vmmctl - dump of hypervisor register state
libvmm - front-end to vmm.ko chardev interface
bhyve was designed and implemented by Neel Natu.
Thanks to the following folk from NetApp who helped to make this available:
Joe CaraDonna
Peter Snyder
Jeff Heller
Sandeep Mann
Steve Miller
Brian Pawlowski
