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: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remov

sys: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

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

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

sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\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spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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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amd64: clean up empty lines in .c and .h files

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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Support software breakpoints in the debug server on Intel CPUs.

- Allow the userland hypervisor to intercept breakpoint exceptions
(BP#) in the guest. A new capability (VM_CAP_BPT_EXIT) is used t

Support software breakpoints in the debug server on Intel CPUs.

- Allow the userland hypervisor to intercept breakpoint exceptions
(BP#) in the guest. A new capability (VM_CAP_BPT_EXIT) is used to
enable this feature. These exceptions are reported to userland via
a new VM_EXITCODE_BPT that includes the length of the original
breakpoint instruction. If userland wishes to pass the exception
through to the guest, it must be explicitly re-injected via
vm_inject_exception().

- Export VMCS_ENTRY_INST_LENGTH as a VM_REG_GUEST_ENTRY_INST_LENGTH
pseudo-register. Injecting a BP# on Intel requires setting this to
the length of the breakpoint instruction. AMD SVM currently ignores
writes to this register (but reports success) and fails to read it.

- Rework the per-vCPU state tracked by the debug server. Rather than
a single 'stepping_vcpu' global, add a structure for each vCPU that
tracks state about that vCPU ('stepping', 'stepped', and
'hit_swbreak'). A global 'stopped_vcpu' tracks which vCPU is
currently reporting an event. Event handlers for MTRAP and
breakpoint exits loop until the associated event is reported to the
debugger.

Breakpoint events are discarded if the breakpoint is not present
when a vCPU resumes in the breakpoint handler to retry submitting
the breakpoint event.

- Maintain a linked-list of active breakpoints in response to the GDB
'Z0' and 'z0' packets.

Reviewed by: markj (earlier version)
MFC after: 2 months
Differential Revision: https://reviews.freebsd.org/D20309

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Provide further mitigation against CVE-2017-5715 by flushing the
return stack buffer (RSB) upon returning from the guest.

This was inspired by this linux commit:
https://git.kernel.org/pub/scm/linux

Provide further mitigation against CVE-2017-5715 by flushing the
return stack buffer (RSB) upon returning from the guest.

This was inspired by this linux commit:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/arch/x86/kvm?id=117cc7a908c83697b0b737d15ae1eb5943afe35b

Reviewed by: grehan
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D14272

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sys/amd64: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - err

sys/amd64: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

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Merge sync of head

MFH: r278968-r280640

Sponsored by: The FreeBSD Foundation

Merge from head

Merge r278538 through r279514.

Merge ^/head r279163 through r279308.

Always emulate MSR_PAT on Intel processors and don't rely on PAT save/restore
capability of VT-x. This lets bhyve run nested in older VMware versions that
don't support the PAT save/restore capabilit

Always emulate MSR_PAT on Intel processors and don't rely on PAT save/restore
capability of VT-x. This lets bhyve run nested in older VMware versions that
don't support the PAT save/restore capability.

Note that the actual value programmed by the guest in MSR_PAT is irrelevant
because bhyve sets the 'Ignore PAT' bit in the nested PTE.

Reported by: marcel
Tested by: Leon Dang (ldang@nahannisys.com)
Sponsored by: Nahanni Systems
MFC after: 2 weeks

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Reintegrate head: r274132-r277384

Sponsored by: The FreeBSD Foundation

Reintegrate head revisions r273096-r277147

Sponsored by: The FreeBSD Foundation

MFhead @ r276594

Merge ^/head r274961 through r276301.

Allow ktr(4) tracing of all guest exceptions via the tunable
"hw.vmm.trace_guest_exceptions". To enable this feature set the tunable
to "1" before loading vmm.ko.

Tracing the guest exceptions can b

Allow ktr(4) tracing of all guest exceptions via the tunable
"hw.vmm.trace_guest_exceptions". To enable this feature set the tunable
to "1" before loading vmm.ko.

Tracing the guest exceptions can be useful when debugging guest triple faults.

Note that there is a performance impact when exception tracing is enabled
since every exception will now trigger a VM-exit.

Also, handle machine check exceptions that happen during guest execution
by vectoring to the host's machine check handler via "int $18".

Discussed with: grehan
MFC after: 2 weeks

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IFC @r269962

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

Merge head from 7/28

Sync to HEAD@r269943.

Add emulation for legacy x86 task switching mechanism.

FreeBSD/i386 uses task switching to handle double fault exceptions and this
change enables that to work.

Reported by: glebius