vmm: implement single-stepping for AMD CPUs

This patch implements single-stepping for AMD CPUs using the RFLAGS.TF
single-stepping mechanism. The GDB stub requests single-stepping
using the VM_CAP_

vmm: implement single-stepping for AMD CPUs

This patch implements single-stepping for AMD CPUs using the RFLAGS.TF
single-stepping mechanism. The GDB stub requests single-stepping
using the VM_CAP_RFLAGS_TF capability. Setting this capability will
set the RFLAGS.TF bit on the selected vCPU, activate DB exception
intercepts, and activate POPF/PUSH instruction intercepts. The
resulting DB exception is then caught by the IDT_DB vmexit handler and
bounced to userland where it is processed by the GDB stub. This patch
also makes sure that the value of the TF bit is correctly updated and
that it is not erroneously propagated into memory. Stepping over PUSHF
will cause the vm_handle_db function to correct the pushed RFLAGS
value and stepping over POPF will update the shadowed TF bit copy.

Reviewed by: jhb
Sponsored by: Google, Inc. (GSoC 2022)
Differential Revision: https://reviews.freebsd.org/D42296

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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spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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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vmm: Expose struct vcpu as an opaque type.

Pass a pointer to the current struct vcpu to the vcpu_init callback
and save this pointer in the CPU-specific vcpu structures.

Add routines to fetch a str

vmm: Expose struct vcpu as an opaque type.

Pass a pointer to the current struct vcpu to the vcpu_init callback
and save this pointer in the CPU-specific vcpu structures.

Add routines to fetch a struct vcpu by index from a VM and to query
the VM and vcpuid from a struct vcpu.

Reviewed by: corvink, markj
Differential Revision: https://reviews.freebsd.org/D37156

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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 svm: Refactor per-vCPU data.

- Allocate VMCBs separately to avoid excessive padding in struct
svm_vcpu.

- Allocate APIC pages dynamically directly in struct vlapic.

- Move vm_mtrr into struc

vmm svm: Refactor per-vCPU data.

- Allocate VMCBs separately to avoid excessive padding in struct
svm_vcpu.

- Allocate APIC pages dynamically directly in struct vlapic.

- Move vm_mtrr into struct svm_vcpu rather than using a separate
parallel array.

Reviewed by: corvink, markj
Differential Revision: https://reviews.freebsd.org/D37148

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bhyve: add support for MTRR

Some guests or driver might depend on MTRR to work properly. E.g. the
nvidia gpu driver won't work without MTRR.

Reviewed by: markj
MFC after: 2 weeks
Sponsored by: Beck

bhyve: add support for MTRR

Some guests or driver might depend on MTRR to work properly. E.g. the
nvidia gpu driver won't work without MTRR.

Reviewed by: markj
MFC after: 2 weeks
Sponsored by: Beckhoff Automation GmbH & Co. KG
Differential Revision: https://reviews.freebsd.org/D33333

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Add SPDX tags to vmm(4).

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

vmm/svm: contigmalloc of the whole svm_softc is excessive

This is a followup to r307903.

struct svm_softc takes more than 200 kilobytes while what we really need
is 3 contiguous pages for I/O permi

vmm/svm: contigmalloc of the whole svm_softc is excessive

This is a followup to r307903.

struct svm_softc takes more than 200 kilobytes while what we really need
is 3 contiguous pages for I/O permission map and 2 contiguous pages for
MSR permission map. Other physically mapped structures have a size of
a single page, so a proper alignment is sufficient for their correct
mapping.

Thus, only the permission maps are allocated with contigmalloc now,
the softc is allocated with a regular malloc.

Additionally, this commit adds a check that malloc returns memory with the
expected page alignment and that contigmalloc does not fail.
Unfortunately, at present svm_vminit() is expected to always succeed and
there is no way to report an error.
So, a contigmalloc failure leads to a panic.
We should probably fix this.

MFC after: 2 weeks

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Clear blocking due to STI or MOV SS in the hypervisor when an instruction is
emulated or when the vcpu incurs an exception. This matches the CPU behavior.

Remove special case code in HLT processing

Clear blocking due to STI or MOV SS in the hypervisor when an instruction is
emulated or when the vcpu incurs an exception. This matches the CPU behavior.

Remove special case code in HLT processing that was clearing the interrupt
shadow. This is now redundant because the interrupt shadow is always cleared
when the vcpu is resumed after an instruction is emulated.

Reported by: David Reed (david.reed@tidalscale.com)
MFC after: 2 weeks

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Remove extraneous comments.

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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Minor cleanup.

Get rid of unused 'svm_feature' from the softc.

Get rid of the redundant 'vcpu_cnt' checks in svm.c. There is a similar check
in vmm.c against 'vm->active_cpus' before the AMD-specif

Minor cleanup.

Get rid of unused 'svm_feature' from the softc.

Get rid of the redundant 'vcpu_cnt' checks in svm.c. There is a similar check
in vmm.c against 'vm->active_cpus' before the AMD-specific code is called.

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

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Make the KTR tracepoints uniform and ensure that every VM-exit is logged.

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

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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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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- SVM nested paging support
- Define data structures to contain the SVM vcpu context
- Define data structures to contain guest and host software context
- Change license in vmcb.h and vmcb.c to remov

- SVM nested paging support
- Define data structures to contain the SVM vcpu context
- Define data structures to contain guest and host software context
- Change license in vmcb.h and vmcb.c to remove references to NetApp that
inadvertently sneaked in when the license text was copied from amdv.c.

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

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vmm: implement single-stepping for AMD CPUs

This patch implements single-stepping for AMD CPUs using the RFLAGS.TF
single-stepping mechanism. The GDB stub requests single-stepping
using the VM_CAP_

vmm: implement single-stepping for AMD CPUs

This patch implements single-stepping for AMD CPUs using the RFLAGS.TF
single-stepping mechanism. The GDB stub requests single-stepping
using the VM_CAP_RFLAGS_TF capability. Setting this capability will
set the RFLAGS.TF bit on the selected vCPU, activate DB exception
intercepts, and activate POPF/PUSH instruction intercepts. The
resulting DB exception is then caught by the IDT_DB vmexit handler and
bounced to userland where it is processed by the GDB stub. This patch
also makes sure that the value of the TF bit is correctly updated and
that it is not erroneously propagated into memory. Stepping over PUSHF
will cause the vm_handle_db function to correct the pushed RFLAGS
value and stepping over POPF will update the shadowed TF bit copy.

Reviewed by: jhb
Sponsored by: Google, Inc. (GSoC 2022)
Differential Revision: https://reviews.freebsd.org/D42296

show more ...

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

show more ...

vmm: Expose struct vcpu as an opaque type.

Pass a pointer to the current struct vcpu to the vcpu_init callback
and save this pointer in the CPU-specific vcpu structures.

Add routines to fetch a str

vmm: Expose struct vcpu as an opaque type.

Pass a pointer to the current struct vcpu to the vcpu_init callback
and save this pointer in the CPU-specific vcpu structures.

Add routines to fetch a struct vcpu by index from a VM and to query
the VM and vcpuid from a struct vcpu.

Reviewed by: corvink, markj
Differential Revision: https://reviews.freebsd.org/D37156

show more ...

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

show more ...