Commit Graph

5677 Commits

Author SHA1 Message Date
Sean Christopherson
f0f37e229c KVM: x86/mmu: Refactor the per-slot level calculation in mapping_level()
Invert the loop which adjusts the allowed page level based on what's
compatible with the associated memslot to use a largest-to-smallest
page size walk.  This paves the way for passing around a "max level"
variable instead of having redundant checks and/or multiple booleans.

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:16:04 +01:00
Sean Christopherson
cb9b88c669 KVM: x86/mmu: Refactor handling of cache consistency with TDP
Pre-calculate the max level for a TDP page with respect to MTRR cache
consistency in preparation of replacing force_pt_level with max_level,
and eventually combining the bulk of nonpaging_page_fault() and
tdp_page_fault() into a common helper.

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:16:03 +01:00
Sean Christopherson
9f1a8526fb KVM: x86/mmu: Move nonpaging_page_fault() below try_async_pf()
Move nonpaging_page_fault() below try_async_pf() to eliminate the
forward declaration of try_async_pf() and to prepare for combining the
bulk of nonpaging_page_fault() and tdp_page_fault() into a common
helper.

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:16:03 +01:00
Sean Christopherson
367fd790b1 KVM: x86/mmu: Fold nonpaging_map() into nonpaging_page_fault()
Fold nonpaging_map() into its sole caller, nonpaging_page_fault(), in
preparation for combining the bulk of nonpaging_page_fault() and
tdp_page_fault() into a common helper.

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:16:03 +01:00
Sean Christopherson
ba7888dde6 KVM: x86/mmu: Move definition of make_mmu_pages_available() up
Move make_mmu_pages_available() above its first user to put it closer
to related code and eliminate a forward declaration.

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:16:02 +01:00
Sean Christopherson
736c291c9f KVM: x86: Use gpa_t for cr2/gpa to fix TDP support on 32-bit KVM
Convert a plethora of parameters and variables in the MMU and page fault
flows from type gva_t to gpa_t to properly handle TDP on 32-bit KVM.

Thanks to PSE and PAE paging, 32-bit kernels can access 64-bit physical
addresses.  When TDP is enabled, the fault address is a guest physical
address and thus can be a 64-bit value, even when both KVM and its guest
are using 32-bit virtual addressing, e.g. VMX's VMCS.GUEST_PHYSICAL is a
64-bit field, not a natural width field.

Using a gva_t for the fault address means KVM will incorrectly drop the
upper 32-bits of the GPA.  Ditto for gva_to_gpa() when it is used to
translate L2 GPAs to L1 GPAs.

Opportunistically rename variables and parameters to better reflect the
dual address modes, e.g. use "cr2_or_gpa" for fault addresses and plain
"addr" instead of "vaddr" when the address may be either a GVA or an L2
GPA.  Similarly, use "gpa" in the nonpaging_page_fault() flows to avoid
a confusing "gpa_t gva" declaration; this also sets the stage for a
future patch to combing nonpaging_page_fault() and tdp_page_fault() with
minimal churn.

Sprinkle in a few comments to document flows where an address is known
to be a GVA and thus can be safely truncated to a 32-bit value.  Add
WARNs in kvm_handle_page_fault() and FNAME(gva_to_gpa_nested)() to help
document such cases and detect bugs.

Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:16:02 +01:00
Sean Christopherson
95145c25a7 KVM: x86: Add a WARN on TIF_NEED_FPU_LOAD in kvm_load_guest_fpu()
WARN once in kvm_load_guest_fpu() if TIF_NEED_FPU_LOAD is observed, as
that would mean that KVM is corrupting userspace's FPU by saving
unknown register state into arch.user_fpu.  Add a comment to explain
why KVM WARNs on TIF_NEED_FPU_LOAD instead of implementing logic
similar to fpu__copy().

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:16:02 +01:00
Sean Christopherson
f958bd2314 KVM: x86: Fix potential put_fpu() w/o load_fpu() on MPX platform
Unlike most state managed by XSAVE, MPX is initialized to zero on INIT.
Because INITs are usually recognized in the context of a VCPU_RUN call,
kvm_vcpu_reset() puts the guest's FPU so that the FPU state is resident
in memory, zeros the MPX state, and reloads FPU state to hardware.  But,
in the unlikely event that an INIT is recognized during
kvm_arch_vcpu_ioctl_get_mpstate() via kvm_apic_accept_events(),
kvm_vcpu_reset() will call kvm_put_guest_fpu() without a preceding
kvm_load_guest_fpu() and corrupt the guest's FPU state (and possibly
userspace's FPU state as well).

Given that MPX is being removed from the kernel[*], fix the bug with the
simple-but-ugly approach of loading the guest's FPU during
KVM_GET_MP_STATE.

[*] See commit f240652b60 ("x86/mpx: Remove MPX APIs").

Fixes: f775b13eed ("x86,kvm: move qemu/guest FPU switching out to vcpu_run")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:16:01 +01:00
Jim Mattson
c90f4d03cc kvm: nVMX: Aesthetic cleanup of handle_vmread and handle_vmwrite
Apply reverse fir tree declaration order, shorten some variable names
to avoid line wrap, reformat a block comment, delete an extra blank
line, and use BIT(10) instead of (1u << 10).

Signed-off-by: Jim Mattson <jmattson@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Peter Shier <pshier@google.com>
Reviewed-by: Oliver Upton <oupton@google.com>
Reviewed-by: Jon Cargille <jcargill@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:16:00 +01:00
Jim Mattson
693e02cc24 kvm: nVMX: VMWRITE checks unsupported field before read-only field
According to the SDM, VMWRITE checks to see if the secondary source
operand corresponds to an unsupported VMCS field before it checks to
see if the secondary source operand corresponds to a VM-exit
information field and the processor does not support writing to
VM-exit information fields.

Fixes: 49f705c532 ("KVM: nVMX: Implement VMREAD and VMWRITE")
Signed-off-by: Jim Mattson <jmattson@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Shier <pshier@google.com>
Reviewed-by: Oliver Upton <oupton@google.com>
Reviewed-by: Jon Cargille <jcargill@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:16:00 +01:00
Jim Mattson
dd2d6042b7 kvm: nVMX: VMWRITE checks VMCS-link pointer before VMCS field
According to the SDM, a VMWRITE in VMX non-root operation with an
invalid VMCS-link pointer results in VMfailInvalid before the validity
of the VMCS field in the secondary source operand is checked.

For consistency, modify both handle_vmwrite and handle_vmread, even
though there was no problem with the latter.

Fixes: 6d894f498f ("KVM: nVMX: vmread/vmwrite: Use shadow vmcs12 if running L2")
Signed-off-by: Jim Mattson <jmattson@google.com>
Cc: Liran Alon <liran.alon@oracle.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Peter Shier <pshier@google.com>
Reviewed-by: Oliver Upton <oupton@google.com>
Reviewed-by: Jon Cargille <jcargill@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:16:00 +01:00
Xiaoyao Li
5e3d394fdd KVM: VMX: Fix the spelling of CPU_BASED_USE_TSC_OFFSETTING
The mis-spelling is found by checkpatch.pl, so fix them.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:15:59 +01:00
Xiaoyao Li
4e2a0bc56a KVM: VMX: Rename NMI_PENDING to NMI_WINDOW
Rename the NMI-window exiting related definitions to match the latest
Intel SDM. No functional changes.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:15:59 +01:00
Xiaoyao Li
9dadc2f918 KVM: VMX: Rename INTERRUPT_PENDING to INTERRUPT_WINDOW
Rename interrupt-windown exiting related definitions to match the
latest Intel SDM. No functional changes.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:15:59 +01:00
Miaohe Lin
0a03cbdac1 KVM: x86: Fix some comment typos
Fix some typos in comment.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 18:15:58 +01:00
Peter Xu
150a84fee8 KVM: X86: Convert the last users of "shorthand = 0" to use macros
Change the last users of "shorthand = 0" to use APIC_DEST_NOSHORT.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 17:33:16 +01:00
Peter Xu
5c69d5c113 KVM: X86: Fix callers of kvm_apic_match_dest() to use correct macros
Callers of kvm_apic_match_dest() should always pass in APIC_DEST_*
macros for either dest_mode and short_hand parameters.  Fix up all the
callers of kvm_apic_match_dest() that are not following the rule.

Since at it, rename the parameter from short_hand to shorthand in
kvm_apic_match_dest(), as suggested by Vitaly.

Reported-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 17:33:15 +01:00
Peter Xu
ac8ef992cd KVM: X86: Drop KVM_APIC_SHORT_MASK and KVM_APIC_DEST_MASK
We have both APIC_SHORT_MASK and KVM_APIC_SHORT_MASK defined for the
shorthand mask.  Similarly, we have both APIC_DEST_MASK and
KVM_APIC_DEST_MASK defined for the destination mode mask.

Drop the KVM_APIC_* macros and replace the only user of them to use
the APIC_DEST_* macros instead.  At the meantime, move APIC_SHORT_MASK
and APIC_DEST_MASK from lapic.c to lapic.h.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 17:33:15 +01:00
Peter Xu
c96001c570 KVM: X86: Use APIC_DEST_* macros properly in kvm_lapic_irq.dest_mode
We were using either APIC_DEST_PHYSICAL|APIC_DEST_LOGICAL or 0|1 to
fill in kvm_lapic_irq.dest_mode.  It's fine only because in most cases
when we check against dest_mode it's against APIC_DEST_PHYSICAL (which
equals to 0).  However, that's not consistent.  We'll have problem
when we want to start checking against APIC_DEST_LOGICAL, which does
not equals to 1.

This patch firstly introduces kvm_lapic_irq_dest_mode() helper to take
any boolean of destination mode and return the APIC_DEST_* macro.
Then, it replaces the 0|1 settings of irq.dest_mode with the helper.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 17:33:14 +01:00
Peter Xu
59508b303e KVM: X86: Move irrelevant declarations out of ioapic.h
kvm_apic_match_dest() is declared in both ioapic.h and lapic.h.
Remove the declaration in ioapic.h.

kvm_apic_compare_prio() is declared in ioapic.h but defined in
lapic.c.  Move the declaration to lapic.h.

kvm_irq_delivery_to_apic() is declared in ioapic.h but defined in
irq_comm.c.  Move the declaration to irq.h.

hyperv.c needs to use kvm_irq_delivery_to_apic(). Include irq.h in
hyperv.c.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 17:33:14 +01:00
Peter Xu
b4b2963616 KVM: X86: Fix kvm_bitmap_or_dest_vcpus() to use irq shorthand
The 3rd parameter of kvm_apic_match_dest() is the irq shorthand,
rather than the irq delivery mode.

Fixes: 7ee30bc132 ("KVM: x86: deliver KVM IOAPIC scan request to target vCPUs")
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 17:33:14 +01:00
Miaohe Lin
fe3c2b4c22 KVM: explicitly set rmap_head->val to 0 in pte_list_desc_remove_entry()
When we reach here, we have desc->sptes[j] = NULL with j = 0.
So we can replace desc->sptes[0] with 0 to make it more clear.
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 17:33:13 +01:00
Miaohe Lin
4fb7b452ce KVM: vmx: remove unreachable statement in vmx_get_msr_feature()
We have no way to reach the final statement, remove it.
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 17:33:12 +01:00
Paolo Bonzini
7adacf5eb2 KVM: x86: use CPUID to locate host page table reserved bits
The comment in kvm_get_shadow_phys_bits refers to MKTME, but the same is actually
true of SME and SEV.  Just use CPUID[0x8000_0008].EAX[7:0] unconditionally if
available, it is simplest and works even if memory is not encrypted.

Cc: stable@vger.kernel.org
Reported-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 17:33:12 +01:00
Linus Torvalds
a313c8e056 PPC:
* Fix a bug where we try to do an ultracall on a system without an ultravisor.
 
 KVM:
 - Fix uninitialised sysreg accessor
 - Fix handling of demand-paged device mappings
 - Stop spamming the console on IMPDEF sysregs
 - Relax mappings of writable memslots
 - Assorted cleanups
 
 MIPS:
 - Now orphan, James Hogan is stepping down
 
 x86:
 - MAINTAINERS change, so long Radim and thanks for all the fish
 - supported CPUID fixes for AMD machines without SPEC_CTRL
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:
 "PPC:
   - Fix a bug where we try to do an ultracall on a system without an
     ultravisor

  KVM:
   - Fix uninitialised sysreg accessor
   - Fix handling of demand-paged device mappings
   - Stop spamming the console on IMPDEF sysregs
   - Relax mappings of writable memslots
   - Assorted cleanups

  MIPS:
   - Now orphan, James Hogan is stepping down

  x86:
   - MAINTAINERS change, so long Radim and thanks for all the fish
   - supported CPUID fixes for AMD machines without SPEC_CTRL"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  MAINTAINERS: remove Radim from KVM maintainers
  MAINTAINERS: Orphan KVM for MIPS
  kvm: x86: Host feature SSBD doesn't imply guest feature AMD_SSBD
  kvm: x86: Host feature SSBD doesn't imply guest feature SPEC_CTRL_SSBD
  KVM: PPC: Book3S HV: Don't do ultravisor calls on systems without ultravisor
  KVM: arm/arm64: Properly handle faulting of device mappings
  KVM: arm64: Ensure 'params' is initialised when looking up sys register
  KVM: arm/arm64: Remove excessive permission check in kvm_arch_prepare_memory_region
  KVM: arm64: Don't log IMP DEF sysreg traps
  KVM: arm64: Sanely ratelimit sysreg messages
  KVM: arm/arm64: vgic: Use wrapper function to lock/unlock all vcpus in kvm_vgic_create()
  KVM: arm/arm64: vgic: Fix potential double free dist->spis in __kvm_vgic_destroy()
  KVM: arm/arm64: Get rid of unused arg in cpu_init_hyp_mode()
2019-12-22 10:26:59 -08:00
Paolo Bonzini
d68321dec1 PPC KVM fix for 5.5
- Fix a bug where we try to do an ultracall on a system without an
   ultravisor.
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Merge tag 'kvm-ppc-fixes-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into kvm-master

PPC KVM fix for 5.5

- Fix a bug where we try to do an ultracall on a system without an
  ultravisor.
2019-12-22 13:18:15 +01:00
Jim Mattson
8715f05269 kvm: x86: Host feature SSBD doesn't imply guest feature AMD_SSBD
The host reports support for the synthetic feature X86_FEATURE_SSBD
when any of the three following hardware features are set:
  CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31]
  CPUID.80000008H:EBX.AMD_SSBD[bit 24]
  CPUID.80000008H:EBX.VIRT_SSBD[bit 25]

Either of the first two hardware features implies the existence of the
IA32_SPEC_CTRL MSR, but CPUID.80000008H:EBX.VIRT_SSBD[bit 25] does
not. Therefore, CPUID.80000008H:EBX.AMD_SSBD[bit 24] should only be
set in the guest if CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31] or
CPUID.80000008H:EBX.AMD_SSBD[bit 24] is set on the host.

Fixes: 4c6903a0f9 ("KVM: x86: fix reporting of AMD speculation bug CPUID leaf")
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Jacob Xu <jacobhxu@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Reported-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-12-18 17:46:35 +01:00
Jim Mattson
396d2e878f kvm: x86: Host feature SSBD doesn't imply guest feature SPEC_CTRL_SSBD
The host reports support for the synthetic feature X86_FEATURE_SSBD
when any of the three following hardware features are set:
  CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31]
  CPUID.80000008H:EBX.AMD_SSBD[bit 24]
  CPUID.80000008H:EBX.VIRT_SSBD[bit 25]

Either of the first two hardware features implies the existence of the
IA32_SPEC_CTRL MSR, but CPUID.80000008H:EBX.VIRT_SSBD[bit 25] does
not. Therefore, CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31] should only be
set in the guest if CPUID.(EAX=7,ECX=0):EDX.SSBD[bit 31] or
CPUID.80000008H:EBX.AMD_SSBD[bit 24] is set on the host.

Fixes: 0c54914d0c ("KVM: x86: use Intel speculation bugs and features as derived in generic x86 code")
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Jacob Xu <jacobhxu@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Reported-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-12-18 17:46:23 +01:00
Linus Torvalds
aedc0650f9 * PPC secure guest support
* small x86 cleanup
 * fix for an x86-specific out-of-bounds write on a ioctl (not guest triggerable,
   data not attacker-controlled)
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull more KVM updates from Paolo Bonzini:

 - PPC secure guest support

 - small x86 cleanup

 - fix for an x86-specific out-of-bounds write on a ioctl (not guest
   triggerable, data not attacker-controlled)

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  kvm: vmx: Stop wasting a page for guest_msrs
  KVM: x86: fix out-of-bounds write in KVM_GET_EMULATED_CPUID (CVE-2019-19332)
  Documentation: kvm: Fix mention to number of ioctls classes
  powerpc: Ultravisor: Add PPC_UV config option
  KVM: PPC: Book3S HV: Support reset of secure guest
  KVM: PPC: Book3S HV: Handle memory plug/unplug to secure VM
  KVM: PPC: Book3S HV: Radix changes for secure guest
  KVM: PPC: Book3S HV: Shared pages support for secure guests
  KVM: PPC: Book3S HV: Support for running secure guests
  mm: ksm: Export ksm_madvise()
  KVM x86: Move kvm cpuid support out of svm
2019-12-04 11:08:30 -08:00
Jim Mattson
7d73710d9c kvm: vmx: Stop wasting a page for guest_msrs
We will never need more guest_msrs than there are indices in
vmx_msr_index. Thus, at present, the guest_msrs array will not exceed
168 bytes.

Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-12-04 12:23:27 +01:00
Paolo Bonzini
433f4ba190 KVM: x86: fix out-of-bounds write in KVM_GET_EMULATED_CPUID (CVE-2019-19332)
The bounds check was present in KVM_GET_SUPPORTED_CPUID but not
KVM_GET_EMULATED_CPUID.

Reported-by: syzbot+e3f4897236c4eeb8af4f@syzkaller.appspotmail.com
Fixes: 84cffe499b ("kvm: Emulate MOVBE", 2013-10-29)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-12-04 12:14:41 +01:00
Peter Gonda
c1de0f2522 KVM x86: Move kvm cpuid support out of svm
Memory encryption support does not have module parameter dependencies
and can be moved into the general x86 cpuid __do_cpuid_ent function.
This changes maintains current behavior of passing through all of
CPUID.8000001F.

Suggested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Peter Gonda <pgonda@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-27 11:39:18 +01:00
Linus Torvalds
1ae78780ed Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Dynamic tick (nohz) updates, perhaps most notably changes to force
     the tick on when needed due to lengthy in-kernel execution on CPUs
     on which RCU is waiting.

   - Linux-kernel memory consistency model updates.

   - Replace rcu_swap_protected() with rcu_prepace_pointer().

   - Torture-test updates.

   - Documentation updates.

   - Miscellaneous fixes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  security/safesetid: Replace rcu_swap_protected() with rcu_replace_pointer()
  net/sched: Replace rcu_swap_protected() with rcu_replace_pointer()
  net/netfilter: Replace rcu_swap_protected() with rcu_replace_pointer()
  net/core: Replace rcu_swap_protected() with rcu_replace_pointer()
  bpf/cgroup: Replace rcu_swap_protected() with rcu_replace_pointer()
  fs/afs: Replace rcu_swap_protected() with rcu_replace_pointer()
  drivers/scsi: Replace rcu_swap_protected() with rcu_replace_pointer()
  drm/i915: Replace rcu_swap_protected() with rcu_replace_pointer()
  x86/kvm/pmu: Replace rcu_swap_protected() with rcu_replace_pointer()
  rcu: Upgrade rcu_swap_protected() to rcu_replace_pointer()
  rcu: Suppress levelspread uninitialized messages
  rcu: Fix uninitialized variable in nocb_gp_wait()
  rcu: Update descriptions for rcu_future_grace_period tracepoint
  rcu: Update descriptions for rcu_nocb_wake tracepoint
  rcu: Remove obsolete descriptions for rcu_barrier tracepoint
  rcu: Ensure that ->rcu_urgent_qs is set before resched IPI
  workqueue: Convert for_each_wq to use built-in list check
  rcu: Several rcu_segcblist functions can be static
  rcu: Remove unused function hlist_bl_del_init_rcu()
  Documentation: Rename rcu_node_context_switch() to rcu_note_context_switch()
  ...
2019-11-26 15:42:43 -08:00
Linus Torvalds
3f59dbcace Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "The main kernel side changes in this cycle were:

   - Various Intel-PT updates and optimizations (Alexander Shishkin)

   - Prohibit kprobes on Xen/KVM emulate prefixes (Masami Hiramatsu)

   - Add support for LSM and SELinux checks to control access to the
     perf syscall (Joel Fernandes)

   - Misc other changes, optimizations, fixes and cleanups - see the
     shortlog for details.

  There were numerous tooling changes as well - 254 non-merge commits.
  Here are the main changes - too many to list in detail:

   - Enhancements to core tooling infrastructure, perf.data, libperf,
     libtraceevent, event parsing, vendor events, Intel PT, callchains,
     BPF support and instruction decoding.

   - There were updates to the following tools:

        perf annotate
        perf diff
        perf inject
        perf kvm
        perf list
        perf maps
        perf parse
        perf probe
        perf record
        perf report
        perf script
        perf stat
        perf test
        perf trace

   - And a lot of other changes: please see the shortlog and Git log for
     more details"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (279 commits)
  perf parse: Fix potential memory leak when handling tracepoint errors
  perf probe: Fix spelling mistake "addrees" -> "address"
  libtraceevent: Fix memory leakage in copy_filter_type
  libtraceevent: Fix header installation
  perf intel-bts: Does not support AUX area sampling
  perf intel-pt: Add support for decoding AUX area samples
  perf intel-pt: Add support for recording AUX area samples
  perf pmu: When using default config, record which bits of config were changed by the user
  perf auxtrace: Add support for queuing AUX area samples
  perf session: Add facility to peek at all events
  perf auxtrace: Add support for dumping AUX area samples
  perf inject: Cut AUX area samples
  perf record: Add aux-sample-size config term
  perf record: Add support for AUX area sampling
  perf auxtrace: Add support for AUX area sample recording
  perf auxtrace: Move perf_evsel__find_pmu()
  perf record: Add a function to test for kernel support for AUX area sampling
  perf tools: Add kernel AUX area sampling definitions
  perf/core: Make the mlock accounting simple again
  perf report: Jump to symbol source view from total cycles view
  ...
2019-11-26 15:04:47 -08:00
Linus Torvalds
ab851d49f6 Merge branch 'x86-iopl-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 iopl updates from Ingo Molnar:
 "This implements a nice simplification of the iopl and ioperm code that
  Thomas Gleixner discovered: we can implement the IO privilege features
  of the iopl system call by using the IO permission bitmap in
  permissive mode, while trapping CLI/STI/POPF/PUSHF uses in user-space
  if they change the interrupt flag.

  This implements that feature, with testing facilities and related
  cleanups"

[ "Simplification" may be an over-statement. The main goal is to avoid
  the cli/sti of iopl by effectively implementing the IO port access
  parts of iopl in terms of ioperm.

  This may end up not workign well in case people actually depend on
  cli/sti being available, or if there are mixed uses of iopl and
  ioperm. We will see..       - Linus ]

* 'x86-iopl-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
  x86/ioperm: Fix use of deprecated config option
  x86/entry/32: Clarify register saving in __switch_to_asm()
  selftests/x86/iopl: Extend test to cover IOPL emulation
  x86/ioperm: Extend IOPL config to control ioperm() as well
  x86/iopl: Remove legacy IOPL option
  x86/iopl: Restrict iopl() permission scope
  x86/iopl: Fixup misleading comment
  selftests/x86/ioperm: Extend testing so the shared bitmap is exercised
  x86/ioperm: Share I/O bitmap if identical
  x86/ioperm: Remove bitmap if all permissions dropped
  x86/ioperm: Move TSS bitmap update to exit to user work
  x86/ioperm: Add bitmap sequence number
  x86/ioperm: Move iobitmap data into a struct
  x86/tss: Move I/O bitmap data into a seperate struct
  x86/io: Speedup schedule out of I/O bitmap user
  x86/ioperm: Avoid bitmap allocation if no permissions are set
  x86/ioperm: Simplify first ioperm() invocation logic
  x86/iopl: Cleanup include maze
  x86/tss: Fix and move VMX BUILD_BUG_ON()
  x86/cpu: Unify cpu_init()
  ...
2019-11-26 11:12:02 -08:00
Linus Torvalds
1d87200446 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Cross-arch changes to move the linker sections for NOTES and
     EXCEPTION_TABLE into the RO_DATA area, where they belong on most
     architectures. (Kees Cook)

   - Switch the x86 linker fill byte from x90 (NOP) to 0xcc (INT3), to
     trap jumps into the middle of those padding areas instead of
     sliding execution. (Kees Cook)

   - A thorough cleanup of symbol definitions within x86 assembler code.
     The rather randomly named macros got streamlined around a
     (hopefully) straightforward naming scheme:

        SYM_START(name, linkage, align...)
        SYM_END(name, sym_type)

        SYM_FUNC_START(name)
        SYM_FUNC_END(name)

        SYM_CODE_START(name)
        SYM_CODE_END(name)

        SYM_DATA_START(name)
        SYM_DATA_END(name)

     etc - with about three times of these basic primitives with some
     label, local symbol or attribute variant, expressed via postfixes.

     No change in functionality intended. (Jiri Slaby)

   - Misc other changes, cleanups and smaller fixes"

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
  x86/entry/64: Remove pointless jump in paranoid_exit
  x86/entry/32: Remove unused resume_userspace label
  x86/build/vdso: Remove meaningless CFLAGS_REMOVE_*.o
  m68k: Convert missed RODATA to RO_DATA
  x86/vmlinux: Use INT3 instead of NOP for linker fill bytes
  x86/mm: Report actual image regions in /proc/iomem
  x86/mm: Report which part of kernel image is freed
  x86/mm: Remove redundant address-of operators on addresses
  xtensa: Move EXCEPTION_TABLE to RO_DATA segment
  powerpc: Move EXCEPTION_TABLE to RO_DATA segment
  parisc: Move EXCEPTION_TABLE to RO_DATA segment
  microblaze: Move EXCEPTION_TABLE to RO_DATA segment
  ia64: Move EXCEPTION_TABLE to RO_DATA segment
  h8300: Move EXCEPTION_TABLE to RO_DATA segment
  c6x: Move EXCEPTION_TABLE to RO_DATA segment
  arm64: Move EXCEPTION_TABLE to RO_DATA segment
  alpha: Move EXCEPTION_TABLE to RO_DATA segment
  x86/vmlinux: Move EXCEPTION_TABLE to RO_DATA segment
  x86/vmlinux: Actually use _etext for the end of the text segment
  vmlinux.lds.h: Allow EXCEPTION_TABLE to live in RO_DATA
  ...
2019-11-26 10:42:40 -08:00
Ingo Molnar
ceb9e77324 Merge branch 'x86/core' into perf/core, to resolve conflicts and to pick up completed topic tree
Conflicts:
	tools/perf/check-headers.sh

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-25 09:09:27 +01:00
Jim Mattson
85c9aae9ac kvm: nVMX: Relax guest IA32_FEATURE_CONTROL constraints
Commit 37e4c997da ("KVM: VMX: validate individual bits of guest
MSR_IA32_FEATURE_CONTROL") broke the KVM_SET_MSRS ABI by instituting
new constraints on the data values that kvm would accept for the guest
MSR, IA32_FEATURE_CONTROL. Perhaps these constraints should have been
opt-in via a new KVM capability, but they were applied
indiscriminately, breaking at least one existing hypervisor.

Relax the constraints to allow either or both of
FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX and
FEATURE_CONTROL_VMXON_ENABLED_INSIDE_SMX to be set when nVMX is
enabled. This change is sufficient to fix the aforementioned breakage.

Fixes: 37e4c997da ("KVM: VMX: validate individual bits of guest MSR_IA32_FEATURE_CONTROL")
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-23 11:34:46 +01:00
Sean Christopherson
ad5996d9a0 KVM: x86: Grab KVM's srcu lock when setting nested state
Acquire kvm->srcu for the duration of ->set_nested_state() to fix a bug
where nVMX derefences ->memslots without holding ->srcu or ->slots_lock.

The other half of nested migration, ->get_nested_state(), does not need
to acquire ->srcu as it is a purely a dump of internal KVM (and CPU)
state to userspace.

Detected as an RCU lockdep splat that is 100% reproducible by running
KVM's state_test selftest with CONFIG_PROVE_LOCKING=y.  Note that the
failing function, kvm_is_visible_gfn(), is only checking the validity of
a gfn, it's not actually accessing guest memory (which is more or less
unsupported during vmx_set_nested_state() due to incorrect MMU state),
i.e. vmx_set_nested_state() itself isn't fundamentally broken.  In any
case, setting nested state isn't a fast path so there's no reason to go
out of our way to avoid taking ->srcu.

  =============================
  WARNING: suspicious RCU usage
  5.4.0-rc7+ #94 Not tainted
  -----------------------------
  include/linux/kvm_host.h:626 suspicious rcu_dereference_check() usage!

               other info that might help us debug this:

  rcu_scheduler_active = 2, debug_locks = 1
  1 lock held by evmcs_test/10939:
   #0: ffff88826ffcb800 (&vcpu->mutex){+.+.}, at: kvm_vcpu_ioctl+0x85/0x630 [kvm]

  stack backtrace:
  CPU: 1 PID: 10939 Comm: evmcs_test Not tainted 5.4.0-rc7+ #94
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
  Call Trace:
   dump_stack+0x68/0x9b
   kvm_is_visible_gfn+0x179/0x180 [kvm]
   mmu_check_root+0x11/0x30 [kvm]
   fast_cr3_switch+0x40/0x120 [kvm]
   kvm_mmu_new_cr3+0x34/0x60 [kvm]
   nested_vmx_load_cr3+0xbd/0x1f0 [kvm_intel]
   nested_vmx_enter_non_root_mode+0xab8/0x1d60 [kvm_intel]
   vmx_set_nested_state+0x256/0x340 [kvm_intel]
   kvm_arch_vcpu_ioctl+0x491/0x11a0 [kvm]
   kvm_vcpu_ioctl+0xde/0x630 [kvm]
   do_vfs_ioctl+0xa2/0x6c0
   ksys_ioctl+0x66/0x70
   __x64_sys_ioctl+0x16/0x20
   do_syscall_64+0x54/0x200
   entry_SYSCALL_64_after_hwframe+0x49/0xbe
  RIP: 0033:0x7f59a2b95f47

Fixes: 8fcc4b5923 ("kvm: nVMX: Introduce KVM_CAP_NESTED_STATE")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-23 11:30:15 +01:00
Sean Christopherson
05c19c2fe1 KVM: x86: Open code shared_msr_update() in its only caller
Fold shared_msr_update() into its sole user to eliminate its pointless
bounds check, its godawful printk, its misleading comment (it's called
under a global lock), and its woefully inaccurate name.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-23 11:29:38 +01:00
Sean Christopherson
24885d1d79 KVM: x86: Remove a spurious export of a static function
A recent change inadvertently exported a static function, which results
in modpost throwing a warning.  Fix it.

Fixes: cbbaa2727a ("KVM: x86: fix presentation of TSX feature in ARCH_CAPABILITIES")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-23 11:28:59 +01:00
Paolo Bonzini
c50d8ae3a1 KVM: x86: create mmu/ subdirectory
Preparatory work for shattering mmu.c into multiple files.  Besides making it easier
to follow, this will also make it possible to write unit tests for various parts.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-21 12:03:50 +01:00
Liran Alon
0155b2b91b KVM: nVMX: Remove unnecessary TLB flushes on L1<->L2 switches when L1 use apic-access-page
According to Intel SDM section 28.3.3.3/28.3.3.4 Guidelines for Use
of the INVVPID/INVEPT Instruction, the hypervisor needs to execute
INVVPID/INVEPT X in case CPU executes VMEntry with VPID/EPTP X and
either: "Virtualize APIC accesses" VM-execution control was changed
from 0 to 1, OR the value of apic_access_page was changed.

In the nested case, the burden falls on L1, unless L0 enables EPT in
vmcs02 but L1 enables neither EPT nor VPID in vmcs12.  For this reason
prepare_vmcs02() and load_vmcs12_host_state() have special code to
request a TLB flush in case L1 does not use EPT but it uses
"virtualize APIC accesses".

This special case however is not necessary. On a nested vmentry the
physical TLB will already be flushed except if all the following apply:

* L0 uses VPID

* L1 uses VPID

* L0 can guarantee TLB entries populated while running L1 are tagged
differently than TLB entries populated while running L2.

If the first condition is false, the processor will flush the TLB
on vmentry to L2.  If the second or third condition are false,
prepare_vmcs02() will request KVM_REQ_TLB_FLUSH.  However, even
if both are true, no extra TLB flush is needed to handle the APIC
access page:

* if L1 doesn't use VPID, the second condition doesn't hold and the
TLB will be flushed anyway.

* if L1 uses VPID, it has to flush the TLB itself with INVVPID and
section 28.3.3.3 doesn't apply to L0.

* even INVEPT is not needed because, if L0 uses EPT, it uses different
EPTP when running L2 than L1 (because guest_mode is part of mmu-role).
In this case SDM section 28.3.3.4 doesn't apply.

Similarly, examining nested_vmx_vmexit()->load_vmcs12_host_state(),
one could note that L0 won't flush TLB only in cases where SDM sections
28.3.3.3 and 28.3.3.4 don't apply.  In particular, if L0 uses different
VPIDs for L1 and L2 (i.e. vmx->vpid != vmx->nested.vpid02), section
28.3.3.3 doesn't apply.

Thus, remove this flush from prepare_vmcs02() and nested_vmx_vmexit().

Side-note: This patch can be viewed as removing parts of commit
fb6c819843 ("kvm: vmx: Flush TLB when the APIC-access address changes”)
that is not relevant anymore since commit
1313cc2bd8 ("kvm: mmu: Add guest_mode to kvm_mmu_page_role”).
i.e. The first commit assumes that if L0 use EPT and L1 doesn’t use EPT,
then L0 will use same EPTP for both L0 and L1. Which indeed required
L0 to execute INVEPT before entering L2 guest. This assumption is
not true anymore since when guest_mode was added to mmu-role.

Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-21 12:03:50 +01:00
Mao Wenan
db5a95ec16 KVM: x86: remove set but not used variable 'called'
Fixes gcc '-Wunused-but-set-variable' warning:

arch/x86/kvm/x86.c: In function kvm_make_scan_ioapic_request_mask:
arch/x86/kvm/x86.c:7911:7: warning: variable called set but not
used [-Wunused-but-set-variable]

It is not used since commit 7ee30bc132 ("KVM: x86: deliver KVM
IOAPIC scan request to target vCPUs")

Signed-off-by: Mao Wenan <maowenan@huawei.com>
Fixes: 7ee30bc132 ("KVM: x86: deliver KVM IOAPIC scan request to target vCPUs")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-21 12:03:49 +01:00
Liran Alon
b11494bcab KVM: nVMX: Do not mark vmcs02->apic_access_page as dirty when unpinning
vmcs->apic_access_page is simply a token that the hypervisor puts into
the PFN of a 4KB EPTE (or PTE if using shadow-paging) that triggers
APIC-access VMExit or APIC virtualization logic whenever a CPU running
in VMX non-root mode read/write from/to this PFN.

As every write either triggers an APIC-access VMExit or write is
performed on vmcs->virtual_apic_page, the PFN pointed to by
vmcs->apic_access_page should never actually be touched by CPU.

Therefore, there is no need to mark vmcs02->apic_access_page as dirty
after unpin it on L2->L1 emulated VMExit or when L1 exit VMX operation.

Reviewed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-21 12:03:48 +01:00
Paolo Bonzini
46f4f0aabc Merge branch 'kvm-tsx-ctrl' into HEAD
Conflicts:
	arch/x86/kvm/vmx/vmx.c
2019-11-21 12:03:40 +01:00
Paolo Bonzini
b07a5c53d4 KVM: vmx: use MSR_IA32_TSX_CTRL to hard-disable TSX on guest that lack it
If X86_FEATURE_RTM is disabled, the guest should not be able to access
MSR_IA32_TSX_CTRL.  We can therefore use it in KVM to force all
transactions from the guest to abort.

Tested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-21 10:01:02 +01:00
Paolo Bonzini
c11f83e062 KVM: vmx: implement MSR_IA32_TSX_CTRL disable RTM functionality
The current guest mitigation of TAA is both too heavy and not really
sufficient.  It is too heavy because it will cause some affected CPUs
(those that have MDS_NO but lack TAA_NO) to fall back to VERW and
get the corresponding slowdown.  It is not really sufficient because
it will cause the MDS_NO bit to disappear upon microcode update, so
that VMs started before the microcode update will not be runnable
anymore afterwards, even with tsx=on.

Instead, if tsx=on on the host, we can emulate MSR_IA32_TSX_CTRL for
the guest and let it run without the VERW mitigation.  Even though
MSR_IA32_TSX_CTRL is quite heavyweight, and we do not want to write
it on every vmentry, we can use the shared MSR functionality because
the host kernel need not protect itself from TSX-based side-channels.

Tested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-21 10:00:59 +01:00
Paolo Bonzini
edef5c36b0 KVM: x86: implement MSR_IA32_TSX_CTRL effect on CPUID
Because KVM always emulates CPUID, the CPUID clear bit
(bit 1) of MSR_IA32_TSX_CTRL must be emulated "manually"
by the hypervisor when performing said emulation.

Right now neither kvm-intel.ko nor kvm-amd.ko implement
MSR_IA32_TSX_CTRL but this will change in the next patch.

Reviewed-by: Jim Mattson <jmattson@google.com>
Tested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-21 09:59:31 +01:00
Paolo Bonzini
de1fca5d6e KVM: x86: do not modify masked bits of shared MSRs
"Shared MSRs" are guest MSRs that are written to the host MSRs but
keep their value until the next return to userspace.  They support
a mask, so that some bits keep the host value, but this mask is
only used to skip an unnecessary MSR write and the value written
to the MSR is always the guest MSR.

Fix this and, while at it, do not update smsr->values[slot].curr if
for whatever reason the wrmsr fails.  This should only happen due to
reserved bits, so the value written to smsr->values[slot].curr
will not match when the user-return notifier and the host value will
always be restored.  However, it is untidy and in rare cases this
can actually avoid spurious WRMSRs on return to userspace.

Cc: stable@vger.kernel.org
Reviewed-by: Jim Mattson <jmattson@google.com>
Tested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-21 09:59:22 +01:00