Commit Graph

53 Commits

Author SHA1 Message Date
Linus Torvalds 312a466155 Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cleanups from Ingo Molnar:
 "Misc cleanups"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/kprobes: Remove trampoline_handler() prototype
  x86/kernel: Fix more -Wmissing-prototypes warnings
  x86: Fix various typos in comments
  x86/headers: Fix -Wmissing-prototypes warning
  x86/process: Avoid unnecessary NULL check in get_wchan()
  x86/traps: Complete prototype declarations
  x86/mce: Fix -Wmissing-prototypes warnings
  x86/gart: Rewrite early_gart_iommu_check() comment
2018-12-26 17:03:51 -08:00
Linus Torvalds 42b00f122c * ARM: selftests improvements, large PUD support for HugeTLB,
single-stepping fixes, improved tracing, various timer and vGIC
 fixes
 
 * x86: Processor Tracing virtualization, STIBP support, some correctness fixes,
 refactorings and splitting of vmx.c, use the Hyper-V range TLB flush hypercall,
 reduce order of vcpu struct, WBNOINVD support, do not use -ftrace for __noclone
 functions, nested guest support for PAUSE filtering on AMD, more Hyper-V
 enlightenments (direct mode for synthetic timers)
 
 * PPC: nested VFIO
 
 * s390: bugfixes only this time
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "ARM:
   - selftests improvements
   - large PUD support for HugeTLB
   - single-stepping fixes
   - improved tracing
   - various timer and vGIC fixes

  x86:
   - Processor Tracing virtualization
   - STIBP support
   - some correctness fixes
   - refactorings and splitting of vmx.c
   - use the Hyper-V range TLB flush hypercall
   - reduce order of vcpu struct
   - WBNOINVD support
   - do not use -ftrace for __noclone functions
   - nested guest support for PAUSE filtering on AMD
   - more Hyper-V enlightenments (direct mode for synthetic timers)

  PPC:
   -  nested VFIO

  s390:
   - bugfixes only this time"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (171 commits)
  KVM: x86: Add CPUID support for new instruction WBNOINVD
  kvm: selftests: ucall: fix exit mmio address guessing
  Revert "compiler-gcc: disable -ftracer for __noclone functions"
  KVM: VMX: Move VM-Enter + VM-Exit handling to non-inline sub-routines
  KVM: VMX: Explicitly reference RCX as the vmx_vcpu pointer in asm blobs
  KVM: x86: Use jmp to invoke kvm_spurious_fault() from .fixup
  MAINTAINERS: Add arch/x86/kvm sub-directories to existing KVM/x86 entry
  KVM/x86: Use SVM assembly instruction mnemonics instead of .byte streams
  KVM/MMU: Flush tlb directly in the kvm_zap_gfn_range()
  KVM/MMU: Flush tlb directly in kvm_set_pte_rmapp()
  KVM/MMU: Move tlb flush in kvm_set_pte_rmapp() to kvm_mmu_notifier_change_pte()
  KVM: Make kvm_set_spte_hva() return int
  KVM: Replace old tlb flush function with new one to flush a specified range.
  KVM/MMU: Add tlb flush with range helper function
  KVM/VMX: Add hv tlb range flush support
  x86/hyper-v: Add HvFlushGuestAddressList hypercall support
  KVM: Add tlb_remote_flush_with_range callback in kvm_x86_ops
  KVM: x86: Disable Intel PT when VMXON in L1 guest
  KVM: x86: Set intercept for Intel PT MSRs read/write
  KVM: x86: Implement Intel PT MSRs read/write emulation
  ...
2018-12-26 11:46:28 -08:00
Sean Christopherson 453eafbe65 KVM: VMX: Move VM-Enter + VM-Exit handling to non-inline sub-routines
Transitioning to/from a VMX guest requires KVM to manually save/load
the bulk of CPU state that the guest is allowed to direclty access,
e.g. XSAVE state, CR2, GPRs, etc...  For obvious reasons, loading the
guest's GPR snapshot prior to VM-Enter and saving the snapshot after
VM-Exit is done via handcoded assembly.  The assembly blob is written
as inline asm so that it can easily access KVM-defined structs that
are used to hold guest state, e.g. moving the blob to a standalone
assembly file would require generating defines for struct offsets.

The other relevant aspect of VMX transitions in KVM is the handling of
VM-Exits.  KVM doesn't employ a separate VM-Exit handler per se, but
rather treats the VMX transition as a mega instruction (with many side
effects), i.e. sets the VMCS.HOST_RIP to a label immediately following
VMLAUNCH/VMRESUME.  The label is then exposed to C code via a global
variable definition in the inline assembly.

Because of the global variable, KVM takes steps to (attempt to) ensure
only a single instance of the owning C function, e.g. vmx_vcpu_run, is
generated by the compiler.  The earliest approach placed the inline
assembly in a separate noinline function[1].  Later, the assembly was
folded back into vmx_vcpu_run() and tagged with __noclone[2][3], which
is still used today.

After moving to __noclone, an edge case was encountered where GCC's
-ftracer optimization resulted in the inline assembly blob being
duplicated.  This was "fixed" by explicitly disabling -ftracer in the
__noclone definition[4].

Recently, it was found that disabling -ftracer causes build warnings
for unsuspecting users of __noclone[5], and more importantly for KVM,
prevents the compiler for properly optimizing vmx_vcpu_run()[6].  And
perhaps most importantly of all, it was pointed out that there is no
way to prevent duplication of a function with 100% reliability[7],
i.e. more edge cases may be encountered in the future.

So to summarize, the only way to prevent the compiler from duplicating
the global variable definition is to move the variable out of inline
assembly, which has been suggested several times over[1][7][8].

Resolve the aforementioned issues by moving the VMLAUNCH+VRESUME and
VM-Exit "handler" to standalone assembly sub-routines.  Moving only
the core VMX transition codes allows the struct indexing to remain as
inline assembly and also allows the sub-routines to be used by
nested_vmx_check_vmentry_hw().  Reusing the sub-routines has a happy
side-effect of eliminating two VMWRITEs in the nested_early_check path
as there is no longer a need to dynamically change VMCS.HOST_RIP.

Note that callers to vmx_vmenter() must account for the CALL modifying
RSP, e.g. must subtract op-size from RSP when synchronizing RSP with
VMCS.HOST_RSP and "restore" RSP prior to the CALL.  There are no great
alternatives to fudging RSP.  Saving RSP in vmx_enter() is difficult
because doing so requires a second register (VMWRITE does not provide
an immediate encoding for the VMCS field and KVM supports Hyper-V's
memory-based eVMCS ABI).  The other more drastic alternative would be
to use eschew VMCS.HOST_RSP and manually save/load RSP using a per-cpu
variable (which can be encoded as e.g. gs:[imm]).  But because a valid
stack is needed at the time of VM-Exit (NMIs aren't blocked and a user
could theoretically insert INT3/INT1ICEBRK at the VM-Exit handler), a
dedicated per-cpu VM-Exit stack would be required.  A dedicated stack
isn't difficult to implement, but it would require at least one page
per CPU and knowledge of the stack in the dumpstack routines.  And in
most cases there is essentially zero overhead in dynamically updating
VMCS.HOST_RSP, e.g. the VMWRITE can be avoided for all but the first
VMLAUNCH unless nested_early_check=1, which is not a fast path.  In
other words, avoiding the VMCS.HOST_RSP by using a dedicated stack
would only make the code marginally less ugly while requiring at least
one page per CPU and forcing the kernel to be aware (and approve) of
the VM-Exit stack shenanigans.

[1] cea15c24ca39 ("KVM: Move KVM context switch into own function")
[2] a3b5ba49a8 ("KVM: VMX: add the __noclone attribute to vmx_vcpu_run")
[3] 104f226bfd ("KVM: VMX: Fold __vmx_vcpu_run() into vmx_vcpu_run()")
[4] 95272c2937 ("compiler-gcc: disable -ftracer for __noclone functions")
[5] https://lkml.kernel.org/r/20181218140105.ajuiglkpvstt3qxs@treble
[6] https://patchwork.kernel.org/patch/8707981/#21817015
[7] https://lkml.kernel.org/r/ri6y38lo23g.fsf@suse.cz
[8] https://lkml.kernel.org/r/20181218212042.GE25620@tassilo.jf.intel.com

Suggested-by: Andi Kleen <ak@linux.intel.com>
Suggested-by: Martin Jambor <mjambor@suse.cz>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Martin Jambor <mjambor@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-21 12:02:50 +01:00
Sean Christopherson 051a2d3e59 KVM: VMX: Explicitly reference RCX as the vmx_vcpu pointer in asm blobs
Use '%% " _ASM_CX"' instead of '%0' to dereference RCX, i.e. the
'struct vcpu_vmx' pointer, in the VM-Enter asm blobs of vmx_vcpu_run()
and nested_vmx_check_vmentry_hw().  Using the symbolic name means that
adding/removing an output parameter(s) requires "rewriting" almost all
of the asm blob, which makes it nearly impossible to understand what's
being changed in even the most minor patches.

Opportunistically improve the code comments.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-21 12:02:43 +01:00
Lan Tianyu 1f3a3e46cc KVM/VMX: Add hv tlb range flush support
This patch is to register tlb_remote_flush_with_range callback with
hv tlb range flush interface.

Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-21 11:28:39 +01:00
Luwei Kang ee85dec2fe KVM: x86: Disable Intel PT when VMXON in L1 guest
Currently, Intel Processor Trace do not support tracing in L1 guest
VMX operation(IA32_VMX_MISC[bit 14] is 0). As mentioned in SDM,
on these type of processors, execution of the VMXON instruction will
clears IA32_RTIT_CTL.TraceEn and any attempt to write IA32_RTIT_CTL
causes a general-protection exception (#GP).

Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-21 11:28:38 +01:00
Chao Peng b08c28960f KVM: x86: Set intercept for Intel PT MSRs read/write
To save performance overhead, disable intercept Intel PT MSRs
read/write when Intel PT is enabled in guest.
MSR_IA32_RTIT_CTL is an exception that will always be intercepted.

Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-21 11:28:37 +01:00
Chao Peng bf8c55d8dc KVM: x86: Implement Intel PT MSRs read/write emulation
This patch implement Intel Processor Trace MSRs read/write
emulation.
Intel PT MSRs read/write need to be emulated when Intel PT
MSRs is intercepted in guest and during live migration.

Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-21 11:28:36 +01:00
Luwei Kang 6c0f0bba85 KVM: x86: Introduce a function to initialize the PT configuration
Initialize the Intel PT configuration when cpuid update.
Include cpuid inforamtion, rtit_ctl bit mask and the number of
address ranges.

Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-21 11:28:36 +01:00
Chao Peng 2ef444f160 KVM: x86: Add Intel PT context switch for each vcpu
Load/Store Intel Processor Trace register in context switch.
MSR IA32_RTIT_CTL is loaded/stored automatically from VMCS.
In Host-Guest mode, we need load/resore PT MSRs only when PT
is enabled in guest.

Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-21 11:28:35 +01:00
Chao Peng 86f5201df0 KVM: x86: Add Intel Processor Trace cpuid emulation
Expose Intel Processor Trace to guest only when
the PT works in Host-Guest mode.

Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-21 11:28:35 +01:00
Chao Peng f99e3daf94 KVM: x86: Add Intel PT virtualization work mode
Intel Processor Trace virtualization can be work in one
of 2 possible modes:

a. System-Wide mode (default):
   When the host configures Intel PT to collect trace packets
   of the entire system, it can leave the relevant VMX controls
   clear to allow VMX-specific packets to provide information
   across VMX transitions.
   KVM guest will not aware this feature in this mode and both
   host and KVM guest trace will output to host buffer.

b. Host-Guest mode:
   Host can configure trace-packet generation while in
   VMX non-root operation for guests and root operation
   for native executing normally.
   Intel PT will be exposed to KVM guest in this mode, and
   the trace output to respective buffer of host and guest.
   In this mode, tht status of PT will be saved and disabled
   before VM-entry and restored after VM-exit if trace
   a virtual machine.

Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-21 11:28:34 +01:00
Jim Mattson 788fc1e9ad kvm: vmx: Allow guest read access to IA32_TSC
Let the guest read the IA32_TSC MSR with the generic RDMSR instruction
as well as the specific RDTSC(P) instructions. Note that the hardware
applies the TSC multiplier and offset (when applicable) to the result of
RDMSR(IA32_TSC), just as it does to the result of RDTSC(P).

Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Reviewed-by: Marc Orr <marcorr@google.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-12-21 11:28:24 +01:00
Jim Mattson 9ebdfe5230 kvm: nVMX: NMI-window and interrupt-window exiting should wake L2 from HLT
According to the SDM, "NMI-window exiting" VM-exits wake a logical
processor from the same inactive states as would an NMI and
"interrupt-window exiting" VM-exits wake a logical processor from the
same inactive states as would an external interrupt. Specifically, they
wake a logical processor from the shutdown state and from the states
entered using the HLT and MWAIT instructions.

Fixes: 6dfacadd58 ("KVM: nVMX: Add support for activity state HLT")
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Suggested-by: Sean Christopherson <sean.j.christopherson@intel.com>
[Squashed comments of two Jim's patches and used the simplified code
 hunk provided by Sean. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-12-21 11:28:24 +01:00
YueHaibing ba7424b200 KVM: VMX: Remove duplicated include from vmx.c
Remove duplicated include.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-12-21 11:28:21 +01:00
Marc Orr b666a4b697 kvm: x86: Dynamically allocate guest_fpu
Previously, the guest_fpu field was embedded in the kvm_vcpu_arch
struct. Unfortunately, the field is quite large, (e.g., 4352 bytes on my
current setup). This bloats the kvm_vcpu_arch struct for x86 into an
order 3 memory allocation, which can become a problem on overcommitted
machines. Thus, this patch moves the fpu state outside of the
kvm_vcpu_arch struct.

With this patch applied, the kvm_vcpu_arch struct is reduced to 15168
bytes for vmx on my setup when building the kernel with kvmconfig.

Suggested-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Marc Orr <marcorr@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 18:00:08 +01:00
Krish Sadhukhan 4e445aee96 KVM: nVMX: Move the checks for Guest Non-Register States to a separate helper function
.. to improve readability and maintainability, and to align the code as per
the layout of the checks in chapter "VM Entries" in Intel SDM vol 3C.

Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com>
Reviewed-by: Mark Kanda <mark.kanda@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 18:00:06 +01:00
Krish Sadhukhan 254b2f3b0f KVM: nVMX: Move the checks for Host Control Registers and MSRs to a separate helper function
.. to improve readability and maintainability, and to align the code as per
the layout of the checks in chapter "VM Entries" in Intel SDM vol 3C.

Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com>
Reviewed-by: Mark Kanda <mark.kanda@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 18:00:06 +01:00
Krish Sadhukhan 5fbf963400 KVM: nVMX: Move the checks for VM-Entry Control Fields to a separate helper function
.. to improve readability and maintainability, and to align the code as per
the layout of the checks in chapter "VM Entries" in Intel SDM vol 3C.

Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com>
Reviewed-by: Mark Kanda <mark.kanda@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 18:00:05 +01:00
Krish Sadhukhan 61446ba75e KVM: nVMX: Move the checks for VM-Exit Control Fields to a separate helper function
.. to improve readability and maintainability, and to align the code as per
the layout of the checks in chapter "VM Entries" in Intel SDM vol 3C.

Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com>
Reviewed-by: Mark Kanda <mark.kanda@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 18:00:04 +01:00
Sean Christopherson f9b245e182 KVM: nVMX: Remove param indirection from nested_vmx_check_msr_switch()
Passing the enum and doing an indirect lookup is silly when we can
simply pass the field directly.  Remove the "fast path" code in
nested_vmx_check_msr_switch_controls() as it's now nothing more than a
redundant check.

Remove the debug message rather than continue passing the enum for the
address field.  Having debug messages for the MSRs themselves is useful
as MSR legality is a huge space, whereas messing up a physical address
means the VMM is fundamentally broken.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 18:00:04 +01:00
Krish Sadhukhan 461b4ba4c7 KVM: nVMX: Move the checks for VM-Execution Control Fields to a separate helper function
.. to improve readability and maintainability, and to align the code as per
the layout of the checks in chapter "VM Entries" in Intel SDM vol 3C.

Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com>
Reviewed-by: Mark Kanda <mark.kanda@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 18:00:03 +01:00
Krish Sadhukhan 16322a3b5e KVM: nVMX: Prepend "nested_vmx_" to check_vmentry_{pre,post}reqs()
.. as they are used only in nested vmx context.

Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com>
Reviewed-by: Mark Kanda <mark.kanda@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 18:00:02 +01:00
Lan Tianyu 53963a70ac KVM/VMX: Check ept_pointer before flushing ept tlb
This patch is to initialize ept_pointer to INVALID_PAGE and check it
before flushing ept tlb. If ept_pointer is invalid, bypass the flush
request.

Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 18:00:02 +01:00
Krish Sadhukhan a0d4f80344 KVM nVMX: MSRs should not be stored if VM-entry fails during or after loading guest state
According to section "VM-entry Failures During or After Loading Guest State"
in Intel SDM vol 3C,

	"No MSRs are saved into the VM-exit MSR-store area."

when bit 31 of the exit reason is set.

Reported-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Suggested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 18:00:01 +01:00
Wei Huang 3d82c565a7 kvm: vmx: add cpu into VMX preemption timer bug list
This patch adds Intel "Xeon CPU E3-1220 V2", with CPUID.01H.EAX=0x000306A8,
into the list of known broken CPUs which fail to support VMX preemption
timer. This bug was found while running the APIC timer test of
kvm-unit-test on this specific CPU, even though the errata info can't be
located in the public domain for this CPU.

Signed-off-by: Wei Huang <wei@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 18:00:00 +01:00
Vitaly Kuznetsov e2e871ab2f x86/kvm/hyper-v: Introduce nested_get_evmcs_version() helper
The upcoming KVM_GET_SUPPORTED_HV_CPUID ioctl will need to return
Enlightened VMCS version in HYPERV_CPUID_NESTED_FEATURES.EAX when
it was enabled.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:59:54 +01:00
Jim Mattson 84c8c5b8f8 kvm: vmx: Skip all SYSCALL MSRs in setup_msrs() when !EFER.SCE
Like IA32_STAR, IA32_LSTAR and IA32_FMASK only need to contain guest
values on VM-entry when the guest is in long mode and EFER.SCE is set.

Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Reviewed-by: Marc Orr <marcorr@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:59:49 +01:00
Jim Mattson db31c8f5af kvm: vmx: Don't set hardware IA32_CSTAR MSR on VM-entry
SYSCALL raises #UD in compatibility mode on Intel CPUs, so it's
pointless to load the guest's IA32_CSTAR value into the hardware MSR.

IA32_CSTAR still provides 48 bits of storage on Intel CPUs that have
CPUID.80000001:EDX.LM[bit 29] set, so we cannot remove it from the
vmx_msr_index[] array.

Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:59:48 +01:00
Jim Mattson 898a811f14 kvm: vmx: Document the need for MSR_STAR in i386 builds
Add a comment explaining why MSR_STAR must be included in
vmx_msr_index[] even for i386 builds.

The elided comment has not been relevant since move_msr_up() was
introduced in commit a75beee6e4 ("KVM: VMX: Avoid saving and
restoring msrs on lightweight vmexit").

Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:59:48 +01:00
Jim Mattson 0023ef39dc kvm: vmx: Set IA32_TSC_AUX for legacy mode guests
RDTSCP is supported in legacy mode as well as long mode. The
IA32_TSC_AUX MSR should be set to the correct guest value before
entering any guest that supports RDTSCP.

Fixes: 4e47c7a6d7 ("KVM: VMX: Add instruction rdtscp support for guest")
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Reviewed-by: Marc Orr <marcorr@google.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:59:47 +01:00
Sean Christopherson 55d2375e58 KVM: nVMX: Move nested code to dedicated files
From a functional perspective, this is (supposed to be) a straight
copy-paste of code.  Code was moved piecemeal to nested.c as not all
code that could/should be moved was obviously nested-only.  The nested
code was then re-ordered as needed to compile, i.e. stats may not show
this is being a "pure" move despite there not being any intended changes
in functionality.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:59:46 +01:00
Sean Christopherson 7c97fcb3b6 KVM: VMX: Expose nested_vmx_allowed() to nested VMX as a non-inline
Exposing only the function allows @nested, i.e. the module param, to be
statically defined in vmx.c, ensuring we aren't unnecessarily checking
said variable in the nested code.  nested_vmx_allowed() is exposed due
to the need to verify nested support in vmx_{get,set}_nested_state().
The downside is that nested_vmx_allowed() likely won't be inlined in
vmx_{get,set}_nested_state(), but that should be a non-issue as they're
not a hot path.  Keeping vmx_{get,set}_nested_state() in vmx.c isn't a
viable option as they need access to several nested-only functions.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:59:45 +01:00
Sean Christopherson 97b7ead392 KVM: VMX: Expose various getters and setters to nested VMX
...as they're used directly by the nested code.  This will allow
moving the bulk of the nested code out of vmx.c without concurrent
changes to vmx.h.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:18:01 +01:00
Sean Christopherson cf3646eb3a KVM: VMX: Expose misc variables needed for nested VMX
Exposed vmx_msr_index, vmx_return and host_efer via vmx.h so that the
nested code can be moved out of vmx.c.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:18:01 +01:00
Sean Christopherson ff241486ac KVM: nVMX: Move "vmcs12 to shadow/evmcs sync" to helper function
...so that the function doesn't need to be created when moving the
nested code out of vmx.c.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:18:00 +01:00
Sean Christopherson 3e8eacccae KVM: nVMX: Call nested_vmx_setup_ctls_msrs() iff @nested is true
...so that it doesn't need access to @nested. The only case where the
provided struct isn't already zeroed is the call from vmx_create_vcpu()
as setup_vmcs_config() zeroes the struct in the other use cases.  This
will allow @nested to be statically defined in vmx.c, i.e. this removes
the last direct reference from nested code.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:17:59 +01:00
Sean Christopherson e4027cfafd KVM: nVMX: Set callbacks for nested functions during hardware setup
...in nested-specific code so that they can eventually be moved out of
vmx.c, e.g. into nested.c.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:17:58 +01:00
Sean Christopherson a3203381ca KVM: VMX: Move the hardware {un}setup functions to the bottom
...so that future patches can reference e.g. @kvm_vmx_exit_handlers
without having to simultaneously move a big chunk of code.  Speaking
from experience, resolving merge conflicts is an absolute nightmare
without pre-moving the code.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:17:58 +01:00
Sean Christopherson 944c346453 KVM: VMX: Move nested hardware/vcpu {un}setup to helper functions
Eventually this will allow us to move the nested VMX code out of vmx.c.
Note that this also effectively wraps @enable_shadow_vmcs with @nested
so that it too can be moved out of vmx.c.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:17:56 +01:00
Sean Christopherson 89b0c9f583 KVM: VMX: Move VMX instruction wrappers to a dedicated header file
VMX has a few hundred lines of code just to wrap various VMX specific
instructions, e.g. VMWREAD, INVVPID, etc...  Move them to a dedicated
header so it's easier to find/isolate the boilerplate.

With this change, more inlines can be moved from vmx.c to vmx.h.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 17:17:27 +01:00
Sean Christopherson 75edce8a45 KVM: VMX: Move eVMCS code to dedicated files
The header, evmcs.h, already exists and contains a fair amount of code,
but there are a few pieces in vmx.c that can be moved verbatim.  In
addition, move an array definition to evmcs.c to prepare for multiple
consumers of evmcs.h.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 14:00:06 +01:00
Sean Christopherson 8373d25d25 KVM: VMX: Add vmx.h to hold VMX definitions
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 14:00:01 +01:00
Sean Christopherson 609363cf81 KVM: nVMX: Move vmcs12 code to dedicated files
vmcs12 is the KVM-defined struct used to track a nested VMCS, e.g. a
VMCS created by L1 for L2.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 12:34:30 +01:00
Sean Christopherson cb1d474b32 KVM: VMX: Move VMCS definitions to dedicated file
This isn't intended to be a pure reflection of hardware, e.g. struct
loaded_vmcs and struct vmcs_host_state are KVM-defined constructs.
Similar to capabilities.h, this is a standalone file to avoid circular
dependencies between yet-to-be-created vmx.h and nested.h files.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 12:34:29 +01:00
Sean Christopherson 2c4fd91d26 KVM: VMX: Expose various module param vars via capabilities.h
Expose the variables associated with various module params that are
needed by the nested VMX code.  There is no ulterior logic for what
variables are/aren't exposed, this is purely "what's needed by the
nested code".

Note that @nested is intentionally not exposed.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 12:34:29 +01:00
Sean Christopherson 3077c19108 KVM: VMX: Move capabilities structs and helpers to dedicated file
Defining a separate capabilities.h as opposed to putting this code in
e.g. vmx.h avoids circular dependencies between (the yet-to-be-added)
vmx.h and nested.h.  The aforementioned circular dependencies are why
struct nested_vmx_msrs also resides in capabilities instead of e.g.
nested.h.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 12:34:28 +01:00
Sean Christopherson 7caaa71108 KVM: VMX: Pass vmx_capability struct to setup_vmcs_config()
...instead of referencing the global struct.  This will allow moving
setup_vmcs_config() to a separate file that may not have access to
the global variable.  Modify nested_vmx_setup_ctls_msrs() appropriately
since vmx_capability.ept may not be accurate when called by
vmx_check_processor_compat().

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 12:34:27 +01:00
Sean Christopherson c73da3fcab KVM: VMX: Properly handle dynamic VM Entry/Exit controls
EFER and PERF_GLOBAL_CTRL MSRs have dedicated VM Entry/Exit controls
that KVM dynamically toggles based on whether or not the guest's value
for each MSRs differs from the host.  Handle the dynamic behavior by
adding a helper that clears the dynamic bits so the bits aren't set
when initializing the VMCS field outside of the dynamic toggling flow.
This makes the handling consistent with similar behavior for other
controls, e.g. pin, exec and sec_exec.  More importantly, it eliminates
two global bools that are stealthily modified by setup_vmcs_config.

Opportunistically clean up a comment and print related to errata for
IA32_PERF_GLOBAL_CTRL.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 12:34:26 +01:00
Sean Christopherson 71d9409e20 KVM: VMX: Move caching of MSR_IA32_XSS to hardware_setup()
MSR_IA32_XSS has no relation to the VMCS whatsoever, it doesn't belong
in setup_vmcs_config() and its reference to host_xss prevents moving
setup_vmcs_config() to a dedicated file.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-12-14 12:34:26 +01:00