vmm: Expose more registers to VM_GET_REGISTER

In a follow-up revision the gdb stub will support sending an XML target
description to gdb, which lets us send additional registers, including
the ones

vmm: Expose more registers to VM_GET_REGISTER

In a follow-up revision the gdb stub will support sending an XML target
description to gdb, which lets us send additional registers, including
the ones added in this patch.

Reviewed by: jhb
MFC after: 1 month
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D43665

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sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

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vmm svm: Add SVM_CTR* wrapper macros.

These macros are similar to VCPU_CTR* but accept a single svm_vcpu
pointer as the first argument instead of separate vm and vcpuid.

Reviewed by: corvink, markj

vmm svm: Add SVM_CTR* wrapper macros.

These macros are similar to VCPU_CTR* but accept a single svm_vcpu
pointer as the first argument instead of separate vm and vcpuid.

Reviewed by: corvink, markj
Differential Revision: https://reviews.freebsd.org/D37153

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vmm: Remove the per-vm cookie argument from vmmops taking a vcpu.

This requires storing a reference to the per-vm cookie in the
CPU-specific vCPU structure. Take advantage of this new field to
remo

vmm: Remove the per-vm cookie argument from vmmops taking a vcpu.

This requires storing a reference to the per-vm cookie in the
CPU-specific vCPU structure. Take advantage of this new field to
remove no-longer-needed function arguments in the CPU-specific
backends. In particular, stop passing the per-vm cookie to functions
that either don't use it or only use it for KTR traces.

Reviewed by: corvink, markj
Differential Revision: https://reviews.freebsd.org/D37152

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vmm: Refactor storage of CPU-dependent per-vCPU data.

Rather than storing static arrays of per-vCPU data in the CPU-specific
per-VM structure, adopt a more dynamic model similar to that used to
mana

vmm: Refactor storage of CPU-dependent per-vCPU data.

Rather than storing static arrays of per-vCPU data in the CPU-specific
per-VM structure, adopt a more dynamic model similar to that used to
manage CPU-specific per-VM data.

That is, add new vmmops methods to init and cleanup a single vCPU.
The init method returns a pointer that is stored in 'struct vcpu' as a
cookie pointer. This cookie pointer is now passed to other vmmops
callbacks in place of the integer index. The index is now only used
in KTR traces and when calling back into the CPU-independent layer.

Reviewed by: corvink, markj
Differential Revision: https://reviews.freebsd.org/D37151

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vmm: Use vm_get_maxcpus() instead of VM_MAXCPU in various places.

Mostly these are loops that iterate over all possible vCPU IDs for a
specific virtual machine.

Reviewed by: corvink, markj
Differen

vmm: Use vm_get_maxcpus() instead of VM_MAXCPU in various places.

Mostly these are loops that iterate over all possible vCPU IDs for a
specific virtual machine.

Reviewed by: corvink, markj
Differential Revision: https://reviews.freebsd.org/D37147

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vmm: Fix snapshots for AMD CPUs

This patch fixes the AMD implementation for snapshotting. It removes
unnecessary vmcb fields that should not be saved and duplicates.

Reviewed by: jhb
Differential

vmm: Fix snapshots for AMD CPUs

This patch fixes the AMD implementation for snapshotting. It removes
unnecessary vmcb fields that should not be saved and duplicates.

Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D33431

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Use vmcb_read/write for the vmcb snapshot functions.

This avoids some unnecessary layers of indirection.

Initial support for bhyve save and restore.

Save and restore (also known as suspend and resume) permits a snapshot
to be taken of a guest's state that can later be resumed. In the
current implement

Initial support for bhyve save and restore.

Save and restore (also known as suspend and resume) permits a snapshot
to be taken of a guest's state that can later be resumed. In the
current implementation, bhyve(8) creates a UNIX domain socket that is
used by bhyvectl(8) to send a request to save a snapshot (and
optionally exit after the snapshot has been taken). A snapshot
currently consists of two files: the first holds a copy of guest RAM,
and the second file holds other guest state such as vCPU register
values and device model state.

To resume a guest, bhyve(8) must be started with a matching pair of
command line arguments to instantiate the same set of device models as
well as a pointer to the saved snapshot.

While the current implementation is useful for several uses cases, it
has a few limitations. The file format for saving the guest state is
tied to the ABI of internal bhyve structures and is not
self-describing (in that it does not communicate the set of device
models present in the system). In addition, the state saved for some
device models closely matches the internal data structures which might
prove a challenge for compatibility of snapshot files across a range
of bhyve versions. The file format also does not currently support
versioning of individual chunks of state. As a result, the current
file format is not a fixed binary format and future revisions to save
and restore will break binary compatiblity of snapshot files. The
goal is to move to a more flexible format that adds versioning,
etc. and at that point to commit to providing a reasonable level of
compatibility. As a result, the current implementation is not enabled
by default. It can be enabled via the WITH_BHYVE_SNAPSHOT=yes option
for userland builds, and the kernel option BHYVE_SHAPSHOT.

Submitted by: Mihai Tiganus, Flavius Anton, Darius Mihai
Submitted by: Elena Mihailescu, Mihai Carabas, Sergiu Weisz
Relnotes: yes
Sponsored by: University Politehnica of Bucharest
Sponsored by: Matthew Grooms (student scholarships)
Sponsored by: iXsystems
Differential Revision: https://reviews.freebsd.org/D19495

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Add SPDX tags to vmm(4).

MFC after: 4 weeks.
Sponsored by: iXsystems Inc.

Save and restore guest debug registers.

Currently most of the debug registers are not saved and restored
during VM transitions allowing guest and host debug register values to
leak into the opposite

Save and restore guest debug registers.

Currently most of the debug registers are not saved and restored
during VM transitions allowing guest and host debug register values to
leak into the opposite context. One result is that hardware
watchpoints do not work reliably within a guest under VT-x.

Due to differences in SVM and VT-x, slightly different approaches are
used.

For VT-x:

- Enable debug register save/restore for VM entry/exit in the VMCS for
DR7 and MSR_DEBUGCTL.
- Explicitly save DR0-3,6 of the guest.
- Explicitly save DR0-3,6-7, MSR_DEBUGCTL, and the trap flag from
%rflags for the host. Note that because DR6 is "software" managed
and not stored in the VMCS a kernel debugger which single steps
through VM entry could corrupt the guest DR6 (since a single step
trap taken after loading the guest DR6 could alter the DR6
register). To avoid this, explicitly disable single-stepping via
the trace flag before loading the guest DR6. A determined debugger
could still defeat this by setting a breakpoint after the guest DR6
was loaded and then single-stepping.

For SVM:
- Enable debug register caching in the VMCB for DR6/DR7.
- Explicitly save DR0-3 of the guest.
- Explicitly save DR0-3,6-7, and MSR_DEBUGCTL for the host. Since SVM
saves the guest DR6 in the VMCB, the race with single-stepping
described for VT-x does not exist.

For both platforms, expose all of the guest DRx values via --get-drX
and --set-drX flags to bhyvectl.

Discussed with: avg, grehan
Tested by: avg (SVM), myself (VT-x)
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D13229

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Don't require <sys/cpuset.h> to be always included before <machine/vmm.h>.

Only a subset of source files that include <machine/vmm.h> need to use the
APIs that require the inclusion of <sys/cpuset.h

Don't require <sys/cpuset.h> to be always included before <machine/vmm.h>.

Only a subset of source files that include <machine/vmm.h> need to use the
APIs that require the inclusion of <sys/cpuset.h>.

MFC after: 1 week

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Reported by: Coverity
CID: 1249760
Reviewed by: neel
Approved by: neel
Sponsored by: QNAP Systems Inc.

Fix bhyvectl so it works correctly on AMD/SVM hosts. Also, add command line
options to display some key VMCB fields.

The set of valid options that can be passed to bhyvectl now depends on the
proces

Fix bhyvectl so it works correctly on AMD/SVM hosts. Also, add command line
options to display some key VMCB fields.

The set of valid options that can be passed to bhyvectl now depends on the
processor type. AMD-specific options are identified by a "--vmcb" or "--avic"
in the option name. Intel-specific options are identified by a "--vmcs" in
the option name.

Submitted by: Anish Gupta (akgupt3@gmail.com)

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Allow more VMCB fields to be cached:
- CR2
- CR0, CR3, CR4 and EFER
- GDT/IDT base/limit fields
- CS/DS/ES/SS selector/base/limit/attrib fields

The caching can be further restricted via the tunable

Allow more VMCB fields to be cached:
- CR2
- CR0, CR3, CR4 and EFER
- GDT/IDT base/limit fields
- CS/DS/ES/SS selector/base/limit/attrib fields

The caching can be further restricted via the tunable 'hw.vmm.svm.vmcb_clean'.

Restructure the code such that the fields above are only modified in a single
place. This makes it easy to invalidate the VMCB cache when any of these fields
is modified.

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Move the VMCB initialization into svm.c in preparation for changes to the
interrupt injection logic.

Discussed with: Anish Gupta (akgupt3@gmail.com)

Move the event injection function into svm.c and add KTR logging for
every event injection.

This in in preparation for changes to SVM guest interrupt injection.

Discussed with: Anish Gupta (akgupt3

Move the event injection function into svm.c and add KTR logging for
every event injection.

This in in preparation for changes to SVM guest interrupt injection.

Discussed with: Anish Gupta (akgupt3@gmail.com)

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Do proper ASID management for guest vcpus.

Prior to this change an ASID was hard allocated to a guest and shared by all
its vcpus. The meant that the number of VMs that could be created was limited

Do proper ASID management for guest vcpus.

Prior to this change an ASID was hard allocated to a guest and shared by all
its vcpus. The meant that the number of VMs that could be created was limited
to the number of ASIDs supported by the CPU. It was also inefficient because
it forced a TLB flush on every VMRUN.

With this change the number of guests that can be created is independent of
the number of available ASIDs. Also, the TLB is flushed only when a new ASID
is allocated.

Discussed with: grehan
Reviewed by: Anish Gupta (akgupt3@gmail.com)

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Merge svm_set_vmcb() and svm_init_vmcb() into a single function that is called
just once when a vcpu is initialized.

Discussed with: Anish Gupta (akgupt3@gmail.com)

An exception is allowed to be injected even if the vcpu is in an interrupt
shadow, so move the check for pending exception before bailing out due to
an interrupt shadow.

Change return type of 'vmcb_

An exception is allowed to be injected even if the vcpu is in an interrupt
shadow, so move the check for pending exception before bailing out due to
an interrupt shadow.

Change return type of 'vmcb_eventinject()' to a void and convert all error
returns into KASSERTs.

Fix VMCB_EXITINTINFO_EC(x) and VMCB_EXITINTINFO_TYPE(x) to do the shift
before masking the result.

Reviewed by: Anish Gupta (akgupt3@gmail.com)

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Set the guest PAT MSR in the VMCB to power-on defaults.

Linux guests accept the values in this register, while *BSD
guests reprogram it. Default values of zero correspond to
PAT_UNCACHEABLE, resulti

Set the guest PAT MSR in the VMCB to power-on defaults.

Linux guests accept the values in this register, while *BSD
guests reprogram it. Default values of zero correspond to
PAT_UNCACHEABLE, resulting in glacial performance.

Thanks to Willem Jan Withagen for first reporting this and
helping out with the investigation.

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Allow the guest's CR2 value to be read/written.
This is required for page-fault injection.

Bring (almost) up-to-date with HEAD.

- use the new virtual APIC page
- update to current bhyve APIs

Tested by Anish with multiple FreeBSD SMP VMs on a Phenom,
and verified by myself with light Free

Bring (almost) up-to-date with HEAD.

- use the new virtual APIC page
- update to current bhyve APIs

Tested by Anish with multiple FreeBSD SMP VMs on a Phenom,
and verified by myself with light FreeBSD VM testing
on a Sempron 3850 APU.

The issues reported with Linux guests are very likely to still
be here, but this sync eliminates the skew between the
project branch and CURRENT, and should help to determine
the causes.

Some follow-on commits will fix minor cosmetic issues.

Submitted by: Anish Gupta (akgupt3@gmail.com)

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Enable memory overcommit for AMD processors.

- No emulation of A/D bits is required since AMD-V RVI
supports A/D bits.
- Enable pmap PT_RVI support(w/o PAT) which is required for
memory over-commi

Enable memory overcommit for AMD processors.

- No emulation of A/D bits is required since AMD-V RVI
supports A/D bits.
- Enable pmap PT_RVI support(w/o PAT) which is required for
memory over-commit support.
- Other minor fixes:
* Make use of VMCB EXITINTINFO field. If a #VMEXIT happens while
delivering an interrupt, EXITINTINFO has all the details that bhyve
needs to inject the same interrupt.
* SVM h/w decode assist code was incomplete - removed for now.
* Some minor code clean-up (more coming).

Submitted by: Anish Gupta (akgupt3@gmail.com)

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