1. 07 4月, 2018 1 次提交
  2. 05 4月, 2018 9 次提交
    • P
      kvm: selftests: add sync_regs_test · 6089ae0b
      Paolo Bonzini 提交于
      This includes the infrastructure to map the test into the guest and
      run code from the test program inside a VM.
      Signed-off-by: NKen Hofsass <hofsass@google.com>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      6089ae0b
    • P
      kvm: selftests: add API testing infrastructure · 783e9e51
      Paolo Bonzini 提交于
      Testsuite contributed by Google and cleaned up by myself for
      inclusion in Linux.
      Signed-off-by: NKen Hofsass <hofsass@google.com>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      783e9e51
    • P
      kvm: x86: fix a compile warning · 3140c156
      Peng Hao 提交于
      fix a "warning: no previous prototype".
      
      Cc: stable@vger.kernel.org
      Signed-off-by: NPeng Hao <peng.hao2@zte.com.cn>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      3140c156
    • W
      KVM: X86: Add Force Emulation Prefix for "emulate the next instruction" · 6c86eedc
      Wanpeng Li 提交于
      There is no easy way to force KVM to run an instruction through the emulator
      (by design as that will expose the x86 emulator as a significant attack-surface).
      However, we do wish to expose the x86 emulator in case we are testing it
      (e.g. via kvm-unit-tests). Therefore, this patch adds a "force emulation prefix"
      that is designed to raise #UD which KVM will trap and it's #UD exit-handler will
      match "force emulation prefix" to run instruction after prefix by the x86 emulator.
      To not expose the x86 emulator by default, we add a module parameter that should
      be off by default.
      
      A simple testcase here:
      
          #include <stdio.h>
          #include <string.h>
      
          #define HYPERVISOR_INFO 0x40000000
      
          #define CPUID(idx, eax, ebx, ecx, edx) \
              asm volatile (\
              "ud2a; .ascii \"kvm\"; cpuid" \
              :"=b" (*ebx), "=a" (*eax), "=c" (*ecx), "=d" (*edx) \
                  :"0"(idx) );
      
          void main()
          {
              unsigned int eax, ebx, ecx, edx;
              char string[13];
      
              CPUID(HYPERVISOR_INFO, &eax, &ebx, &ecx, &edx);
              *(unsigned int *)(string + 0) = ebx;
              *(unsigned int *)(string + 4) = ecx;
              *(unsigned int *)(string + 8) = edx;
      
              string[12] = 0;
              if (strncmp(string, "KVMKVMKVM\0\0\0", 12) == 0)
                  printf("kvm guest\n");
              else
                  printf("bare hardware\n");
          }
      Suggested-by: NAndrew Cooper <andrew.cooper3@citrix.com>
      Reviewed-by: NRadim Krčmář <rkrcmar@redhat.com>
      Reviewed-by: NLiran Alon <liran.alon@oracle.com>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Radim Krčmář <rkrcmar@redhat.com>
      Cc: Andrew Cooper <andrew.cooper3@citrix.com>
      Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      Cc: Liran Alon <liran.alon@oracle.com>
      Signed-off-by: NWanpeng Li <wanpengli@tencent.com>
      [Correctly handle usermode exits. - Paolo]
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      6c86eedc
    • W
      KVM: X86: Introduce handle_ud() · 082d06ed
      Wanpeng Li 提交于
      Introduce handle_ud() to handle invalid opcode, this function will be
      used by later patches.
      Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      Reviewed-by: NLiran Alon <liran.alon@oracle.com>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Radim KrÄmář <rkrcmar@redhat.com>
      Cc: Andrew Cooper <andrew.cooper3@citrix.com>
      Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      Cc: Liran Alon <liran.alon@oracle.com>
      Signed-off-by: NWanpeng Li <wanpengli@tencent.com>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      082d06ed
    • P
      KVM: vmx: unify adjacent #ifdefs · 4fde8d57
      Paolo Bonzini 提交于
      vmx_save_host_state has multiple ifdefs for CONFIG_X86_64 that have
      no other code between them.  Simplify by reducing them to a single
      conditional.
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      4fde8d57
    • A
      x86: kvm: hide the unused 'cpu' variable · 51e8a8cc
      Arnd Bergmann 提交于
      The local variable was newly introduced but is only accessed in one
      place on x86_64, but not on 32-bit:
      
      arch/x86/kvm/vmx.c: In function 'vmx_save_host_state':
      arch/x86/kvm/vmx.c:2175:6: error: unused variable 'cpu' [-Werror=unused-variable]
      
      This puts it into another #ifdef.
      
      Fixes: 35060ed6 ("x86/kvm/vmx: avoid expensive rdmsr for MSR_GS_BASE")
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      51e8a8cc
    • S
      KVM: VMX: remove bogus WARN_ON in handle_ept_misconfig · c75d0edc
      Sean Christopherson 提交于
      Remove the WARN_ON in handle_ept_misconfig() as it is unnecessary
      and causes false positives.  Return the unmodified result of
      kvm_mmu_page_fault() instead of converting a system error code to
      KVM_EXIT_UNKNOWN so that userspace sees the error code of the
      actual failure, not a generic "we don't know what went wrong".
      
        * kvm_mmu_page_fault() will WARN if reserved bits are set in the
          SPTEs, i.e. it covers the case where an EPT misconfig occurred
          because of a KVM bug.
      
        * The WARN_ON will fire on any system error code that is hit while
          handling the fault, e.g. -ENOMEM from mmu_topup_memory_caches()
          while handling a legitmate MMIO EPT misconfig or -EFAULT from
          kvm_handle_bad_page() if the corresponding HVA is invalid.  In
          either case, userspace should receive the original error code
          and firing a warning is incorrect behavior as KVM is operating
          as designed.
      Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      c75d0edc
    • S
      Revert "KVM: X86: Fix SMRAM accessing even if VM is shutdown" · 2c151b25
      Sean Christopherson 提交于
      The bug that led to commit 95e057e2
      was a benign warning (no adverse affects other than the warning
      itself) that was detected by syzkaller.  Further inspection shows
      that the WARN_ON in question, in handle_ept_misconfig(), is
      unnecessary and flawed (this was also briefly discussed in the
      original patch: https://patchwork.kernel.org/patch/10204649).
      
        * The WARN_ON is unnecessary as kvm_mmu_page_fault() will WARN
          if reserved bits are set in the SPTEs, i.e. it covers the case
          where an EPT misconfig occurred because of a KVM bug.
      
        * The WARN_ON is flawed because it will fire on any system error
          code that is hit while handling the fault, e.g. -ENOMEM can be
          returned by mmu_topup_memory_caches() while handling a legitmate
          MMIO EPT misconfig.
      
      The original behavior of returning -EFAULT when userspace munmaps
      an HVA without first removing the memslot is correct and desirable,
      i.e. KVM is letting userspace know it has generated a bad address.
      Returning RET_PF_EMULATE masks the WARN_ON in the EPT misconfig path,
      but does not fix the underlying bug, i.e. the WARN_ON is bogus.
      
      Furthermore, returning RET_PF_EMULATE has the unwanted side effect of
      causing KVM to attempt to emulate an instruction on any page fault
      with an invalid HVA translation, e.g. a not-present EPT violation
      on a VM_PFNMAP VMA whose fault handler failed to insert a PFN.
      
        * There is no guarantee that the fault is directly related to the
          instruction, i.e. the fault could have been triggered by a side
          effect memory access in the guest, e.g. while vectoring a #DB or
          writing a tracing record.  This could cause KVM to effectively
          mask the fault if KVM doesn't model the behavior leading to the
          fault, i.e. emulation could succeed and resume the guest.
      
        * If emulation does fail, KVM will return EMULATION_FAILED instead
          of -EFAULT, which is a red herring as the user will either debug
          a bogus emulation attempt or scratch their head wondering why we
          were attempting emulation in the first place.
      
      TL;DR: revert to returning -EFAULT and remove the bogus WARN_ON in
      handle_ept_misconfig in a future patch.
      
      This reverts commit 95e057e2.
      Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      2c151b25
  3. 04 4月, 2018 2 次提交
    • S
      kvm: Add emulation for movups/movupd · 29916968
      Stefan Fritsch 提交于
      This is very similar to the aligned versions movaps/movapd.
      
      We have seen the corresponding emulation failures with openbsd as guest
      and with Windows 10 with intel HD graphics pass through.
      Signed-off-by: NChristian Ehrhardt <christian_ehrhardt@genua.de>
      Signed-off-by: NStefan Fritsch <sf@sfritsch.de>
      Reviewed-by: NRadim Krčmář <rkrcmar@redhat.com>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      29916968
    • S
      KVM: VMX: raise internal error for exception during invalid protected mode state · add5ff7a
      Sean Christopherson 提交于
      Exit to userspace with KVM_INTERNAL_ERROR_EMULATION if we encounter
      an exception in Protected Mode while emulating guest due to invalid
      guest state.  Unlike Big RM, KVM doesn't support emulating exceptions
      in PM, i.e. PM exceptions are always injected via the VMCS.  Because
      we will never do VMRESUME due to emulation_required, the exception is
      never realized and we'll keep emulating the faulting instruction over
      and over until we receive a signal.
      
      Exit to userspace iff there is a pending exception, i.e. don't exit
      simply on a requested event. The purpose of this check and exit is to
      aid in debugging a guest that is in all likelihood already doomed.
      Invalid guest state in PM is extremely limited in normal operation,
      e.g. it generally only occurs for a few instructions early in BIOS,
      and any exception at this time is all but guaranteed to be fatal.
      Non-vectored interrupts, e.g. INIT, SIPI and SMI, can be cleanly
      handled/emulated, while checking for vectored interrupts, e.g. INTR
      and NMI, without hitting false positives would add a fair amount of
      complexity for almost no benefit (getting hit by lightning seems
      more likely than encountering this specific scenario).
      
      Add a WARN_ON_ONCE to vmx_queue_exception() if we try to inject an
      exception via the VMCS and emulation_required is true.
      Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      add5ff7a
  4. 30 3月, 2018 1 次提交
  5. 29 3月, 2018 22 次提交
  6. 28 3月, 2018 5 次提交
    • A
      KVM: x86: Fix perf timer mode IP reporting · dd60d217
      Andi Kleen 提交于
      KVM and perf have a special backdoor mechanism to report the IP for interrupts
      re-executed after vm exit. This works for the NMIs that perf normally uses.
      
      However when perf is in timer mode it doesn't work because the timer interrupt
      doesn't get this special treatment. This is common when KVM is running
      nested in another hypervisor which may not implement the PMU, so only
      timer mode is available.
      
      Call the functions to set up the backdoor IP also for non NMI interrupts.
      
      I renamed the functions to set up the backdoor IP reporting to be more
      appropiate for their new use.  The SVM change is only compile tested.
      
      v2: Moved the functions inline.
      For the normal interrupt case the before/after functions are now
      called from x86.c, not arch specific code.
      For the NMI case we still need to call it in the architecture
      specific code, because it's already needed in the low level *_run
      functions.
      Signed-off-by: NAndi Kleen <ak@linux.intel.com>
      [Removed unnecessary calls from arch handle_external_intr. - Radim]
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      dd60d217
    • R
      Merge tag 'kvm-arm-for-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm · abe7a458
      Radim Krčmář 提交于
      KVM/ARM updates for v4.17
      
      - VHE optimizations
      - EL2 address space randomization
      - Variant 3a mitigation for Cortex-A57 and A72
      - The usual vgic fixes
      - Various minor tidying-up
      abe7a458
    • M
      arm64: Add temporary ERRATA_MIDR_ALL_VERSIONS compatibility macro · dc6ed61d
      Marc Zyngier 提交于
      MIDR_ALL_VERSIONS is changing, and won't have the same meaning
      in 4.17, and the right thing to use will be ERRATA_MIDR_ALL_VERSIONS.
      
      In order to cope with the merge window, let's add a compatibility
      macro that will allow a relatively smooth transition, and that
      can be removed post 4.17-rc1.
      Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
      dc6ed61d
    • M
      Revert "arm64: KVM: Use SMCCC_ARCH_WORKAROUND_1 for Falkor BP hardening" · adc91ab7
      Marc Zyngier 提交于
      Creates far too many conflicts with arm64/for-next/core, to be
      resent post -rc1.
      
      This reverts commit f9f5dc19.
      Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
      adc91ab7
    • P
      KVM: PPC: Book3S HV: Use __gfn_to_pfn_memslot() in page fault handler · 31c8b0d0
      Paul Mackerras 提交于
      This changes the hypervisor page fault handler for radix guests to use
      the generic KVM __gfn_to_pfn_memslot() function instead of using
      get_user_pages_fast() and then handling the case of VM_PFNMAP vmas
      specially.  The old code missed the case of VM_IO vmas; with this
      change, VM_IO vmas will now be handled correctly by code within
      __gfn_to_pfn_memslot.
      
      Currently, __gfn_to_pfn_memslot calls hva_to_pfn, which only uses
      __get_user_pages_fast for the initial lookup in the cases where
      either atomic or async is set.  Since we are not setting either
      atomic or async, we do our own __get_user_pages_fast first, for now.
      
      This also adds code to check for the KVM_MEM_READONLY flag on the
      memslot.  If it is set and this is a write access, we synthesize a
      data storage interrupt for the guest.
      
      In the case where the page is not normal RAM (i.e. page == NULL in
      kvmppc_book3s_radix_page_fault(), we read the PTE from the Linux page
      tables because we need the mapping attribute bits as well as the PFN.
      (The mapping attribute bits indicate whether accesses have to be
      non-cacheable and/or guarded.)
      Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>
      31c8b0d0