1
linux/arch/x86/kvm
Sean Christopherson aa0d42cacf KVM: VMX: Bury Intel PT virtualization (guest/host mode) behind CONFIG_BROKEN
Hide KVM's pt_mode module param behind CONFIG_BROKEN, i.e. disable support
for virtualizing Intel PT via guest/host mode unless BROKEN=y.  There are
myriad bugs in the implementation, some of which are fatal to the guest,
and others which put the stability and health of the host at risk.

For guest fatalities, the most glaring issue is that KVM fails to ensure
tracing is disabled, and *stays* disabled prior to VM-Enter, which is
necessary as hardware disallows loading (the guest's) RTIT_CTL if tracing
is enabled (enforced via a VMX consistency check).  Per the SDM:

  If the logical processor is operating with Intel PT enabled (if
  IA32_RTIT_CTL.TraceEn = 1) at the time of VM entry, the "load
  IA32_RTIT_CTL" VM-entry control must be 0.

On the host side, KVM doesn't validate the guest CPUID configuration
provided by userspace, and even worse, uses the guest configuration to
decide what MSRs to save/load at VM-Enter and VM-Exit.  E.g. configuring
guest CPUID to enumerate more address ranges than are supported in hardware
will result in KVM trying to passthrough, save, and load non-existent MSRs,
which generates a variety of WARNs, ToPA ERRORs in the host, a potential
deadlock, etc.

Fixes: f99e3daf94 ("KVM: x86: Add Intel PT virtualization work mode")
Cc: stable@vger.kernel.org
Cc: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Tested-by: Adrian Hunter <adrian.hunter@intel.com>
Message-ID: <20241101185031.1799556-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-11-08 05:57:13 -05:00
..
mmu KVM: x86/mmu: Add lockdep assert to enforce safe usage of kvm_unmap_gfn_range() 2024-10-20 07:31:05 -04:00
svm kvm: svm: Fix gctx page leak on invalid inputs 2024-11-08 05:57:13 -05:00
vmx KVM: VMX: Bury Intel PT virtualization (guest/host mode) behind CONFIG_BROKEN 2024-11-08 05:57:13 -05:00
.gitignore KVM: x86: use a separate asm-offsets.c file 2022-11-09 12:10:17 -05:00
cpuid.c KVM: x86: Advertise AVX10.1 CPUID to userspace 2024-08-22 11:25:25 -07:00
cpuid.h KVM: x86: Bury guest_cpuid_is_amd_or_hygon() in cpuid.c 2024-06-10 14:29:39 -07:00
debugfs.c KVM: Get rid of return value from kvm_arch_create_vm_debugfs() 2024-02-23 21:44:58 +00:00
emulate.c ARM: 2024-07-20 12:41:03 -07:00
fpu.h KVM: x86: Move FPU register accessors into fpu.h 2021-06-17 13:09:24 -04:00
governed_features.h KVM: x86: Use KVM-governed feature framework to track "LAM enabled" 2023-11-28 17:54:09 -08:00
hyperv.c KVM: x86: Introduce kvm_x86_call() to simplify static calls of kvm_x86_ops 2024-07-16 12:14:12 -04:00
hyperv.h KVM: x86: hyper-v: Remove unused inline function kvm_hv_free_pa_page() 2024-08-13 09:28:48 -04:00
i8254.c KVM: x86: Unify pr_fmt to use module name for all KVM modules 2022-12-29 15:47:35 -05:00
i8254.h KVM: x86: PIT: Preserve state of speaker port data bit 2022-06-08 13:06:20 -04:00
i8259.c KVM: x86: Fix poll command 2023-06-01 13:44:13 -07:00
ioapic.c KVM: x86/ioapic: Resample the pending state of an IRQ when unmasking 2023-03-27 10:13:28 -04:00
ioapic.h x86/kvm: remove unused ack_notifier callbacks 2021-11-18 07:05:57 -05:00
irq_comm.c KVM: x86: Don't re-setup empty IRQ routing when KVM_CAP_SPLIT_IRQCHIP 2024-06-11 14:18:40 -07:00
irq.c KVM: x86: Fold kvm_get_apic_interrupt() into kvm_cpu_get_interrupt() 2024-09-09 20:15:01 -07:00
irq.h KVM: x86: Don't re-setup empty IRQ routing when KVM_CAP_SPLIT_IRQCHIP 2024-06-11 14:18:40 -07:00
Kconfig KVM: x86: leave kvm.ko out of the build if no vendor module is requested 2024-10-06 03:53:41 -04:00
kvm_cache_regs.h KVM: x86: Introduce kvm_x86_call() to simplify static calls of kvm_x86_ops 2024-07-16 12:14:12 -04:00
kvm_emulate.h KVM: x86: Use "is Intel compatible" helper to emulate SYSCALL in !64-bit 2024-06-10 14:29:38 -07:00
kvm_onhyperv.c KVM: x86/mmu: Move filling of Hyper-V's TLB range struct into Hyper-V code 2023-04-10 15:17:29 -07:00
kvm_onhyperv.h KVM: x86: Move Hyper-V partition assist page out of Hyper-V emulation context 2023-12-07 09:34:01 -08:00
kvm-asm-offsets.c KVM: SVM: move MSR_IA32_SPEC_CTRL save/restore to assembly 2022-11-09 12:25:53 -05:00
lapic.c KVM: x86: Unconditionally set irr_pending when updating APICv state 2024-11-08 05:57:13 -05:00
lapic.h Merge tag 'kvm-x86-vmx-6.12' of https://github.com/kvm-x86/linux into HEAD 2024-09-17 12:41:23 -04:00
Makefile KVM: x86: leave kvm.ko out of the build if no vendor module is requested 2024-10-06 03:53:41 -04:00
mmu.h KVM: x86: Remove some unused declarations 2024-09-09 20:12:43 -07:00
mtrr.c KVM: x86: Remove VMX support for virtualizing guest MTRR memtypes 2024-06-05 08:13:14 -07:00
pmu.c KVM: x86/pmu: Add kvm_pmu_call() to simplify static calls of kvm_pmu_ops 2024-07-16 12:14:12 -04:00
pmu.h KVM: x86/pmu: Introduce distinct macros for GP/fixed counter max number 2024-06-28 09:12:16 -07:00
reverse_cpuid.h KVM: x86: Advertise AVX10.1 CPUID to userspace 2024-08-22 11:25:25 -07:00
smm.c KVM: x86: Forcibly leave nested if RSM to L2 hits shutdown 2024-09-09 20:09:49 -07:00
smm.h KVM: x86: smm: preserve interrupt shadow in SMRAM 2022-11-09 12:31:26 -05:00
trace.h KVM: x86: Introduce kvm_x86_call() to simplify static calls of kvm_x86_ops 2024-07-16 12:14:12 -04:00
tss.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
x86.c Merge tag 'kvm-x86-vmx-6.12' of https://github.com/kvm-x86/linux into HEAD 2024-09-17 12:41:23 -04:00
x86.h Merge tag 'kvm-x86-pat_vmx_msrs-6.12' of https://github.com/kvm-x86/linux into HEAD 2024-09-17 12:40:39 -04:00
xen.c KVM: x86: Introduce kvm_x86_call() to simplify static calls of kvm_x86_ops 2024-07-16 12:14:12 -04:00
xen.h KVM: x86/xen: inject vCPU upcall vector when local APIC is enabled 2024-03-04 16:22:36 -08:00