VM-exit and ultimately on whether nRIP is valid. This allows us to update
the %rip after the emulation is finished so any exceptions triggered during
the emulation will point to the right instruction.
Don't attempt to handle INS/OUTS VM-exits unless the DecodeAssist capability
is available. The effective segment field in EXITINFO1 is not valid without
this capability.
Add VM_EXITCODE_SVM to flag SVM VM-exits that cannot be handled. Provide the
VMCB fields exitinfo1 and exitinfo2 as collateral to help with debugging.
Provide a SVM VM-exit handler to dump the exitcode, exitinfo1 and exitinfo2
fields in bhyve(8).
Reviewed by: Anish Gupta (akgupt3@gmail.com)
Reviewed by: grehan
- Don't enable the HLT intercept by default. It will be enabled by bhyve(8)
if required. Prior to this change HLT exiting was always enabled making
the "-H" option to bhyve(8) meaningless.
- Recognize a VM exit triggered by a non-maskable interrupt. Prior to this
change the exit would be punted to userspace and the virtual machine would
terminate.
instruction bytes in the VMCB on a nested page fault. This is useful because
it saves having to walk the guest page tables to fetch the instruction.
vie_init() now takes two additional parameters 'inst_bytes' and 'inst_len'
that map directly to 'vie->inst[]' and 'vie->num_valid'.
The instruction emulation handler skips calling 'vmm_fetch_instruction()'
if 'vie->num_valid' is non-zero.
The use of this capability can be turned off by setting the sysctl/tunable
'hw.vmm.svm.disable_npf_assist' to '1'.
Reviewed by: Anish Gupta (akgupt3@gmail.com)
Discussed with: grehan
window exiting. This simply involves setting V_IRQ and enabling the VINTR
intercept. This instructs the CPU to trap back into the hypervisor as soon
as an interrupt can be injected into the guest. The pending interrupt is
then injected via the traditional event injection mechanism.
Rework vcpu interrupt injection so that Linux guests now idle with host cpu
utilization close to 0%.
Reviewed by: Anish Gupta (earlier version)
Discussed with: grehan
Provide APIs svm_enable_intercept()/svm_disable_intercept() to add/delete
VMCB intercepts. These APIs ensure that the VMCB state cache is invalidated
when intercepts are modified.
Each intercept is identified as a (index,bitmask) tuple. For e.g., the
VINTR intercept is identified as (VMCB_CTRL1_INTCPT,VMCB_INTCPT_VINTR).
The first 20 bytes in control area that are used to enable intercepts
are represented as 'uint32_t intercept[5]' in 'struct vmcb_ctrl'.
Modify svm_setcap() and svm_getcap() to use the new APIs.
Discussed with: Anish Gupta (akgupt3@gmail.com)
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)
function restore_host_tss().
Don't bother to restore MSR_KGSBASE after a #VMEXIT since it is not used in
the kernel. It will be restored on return to userspace.
Discussed with: Anish Gupta (akgupt3@gmail.com)
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)
is sampled "atomically". Any interrupts after this point will be held pending
by the CPU until the guest starts executing and will immediately trigger a
#VMEXIT.
Reviewed by: Anish Gupta (akgupt3@gmail.com)
Handle ExtINT injection for SVM. The HPET emulation
will inject a legacy interrupt at startup, and if this
isn't handled, will result in the HLT-exit code assuming
there are outstanding ExtINTs and return without sleeping.
svm_inj_interrupts() needs more changes to bring it up
to date with the VT-x version: these are forthcoming.
Reviewed by: neel
Remove CR2 save/restore - the guest restore/save is done
in hardware, and there is no need to save/restore the host
version (same as VT-x).
Submitted by: neel (SVM segment descriptor 'P' bit code)
Reviewed by: neel
- 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)
- Convert VMM_CTR to VCPU_CTR KTR macros
- Special handling of halt, save rflags for VMM layer to emulate
halt for vcpu(sleep to be awakened by interrupt or stop it)
- Cleanup of RVI exit handling code
Submitted by: Anish Gupta (akgupt3@gmail.com)
Reviewed by: grehan
- 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)
all vcpus belonging to a guest. This means that when different vcpus belonging
to the same guest are executing on the same host cpu there may be "leakage"
in the mappings created by one vcpu to another.
The proper fix for this is being worked on and will be committed shortly.
In the meantime workaround this bug by flushing the guest TLB entries on every
VM entry.
Submitted by: Anish Gupta (akgupt3@gmail.com)
hang on console output (due to a missing interrupt).
SVM does exit processing and then handles ASTPENDING which
overwrites the already handled SVM exit cause and corrupts
virtual machine state. For example, if the SVM exit was due to
an I/O port access but the main loop detected an ASTPENDING,
the exit would be processed as ASTPENDING and leave the
device (e.g. emulated UART) for that I/O port in bad state.
Submitted by: Anish Gupta (akgupt3@gmail.com)
Reviewed by: grehan
