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2023-03-24treewide: Trace IPIs sent via smp_send_reschedule()Valentin Schneider1-0/+4
To be able to trace invocations of smp_send_reschedule(), rename the arch-specific definitions of it to arch_smp_send_reschedule() and wrap it into an smp_send_reschedule() that contains a tracepoint. Changes to include the declaration of the tracepoint were driven by the following coccinelle script: @func_use@ @@ smp_send_reschedule(...); @include@ @@ #include <trace/events/ipi.h> @no_include depends on func_use && !include@ @@ #include <...> + + #include <trace/events/ipi.h> [csky bits] [riscv bits] Signed-off-by: Valentin Schneider <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Acked-by: Guo Ren <[email protected]> Acked-by: Palmer Dabbelt <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2023-03-22KVM: nSVM: Implement support for nested VNMISantosh Shukla3-0/+45
Allow L1 to use vNMI to accelerate its injection of NMI to L2 by propagating vNMI int_ctl bits from/to vmcb12 to/from vmcb02. To handle both the case where vNMI is enabled for L1 and L2, and where vNMI is enabled for L1 but _not_ L2, move pending L1 vNMIs to nmi_pending on nested VM-Entry and raise KVM_REQ_EVENT, i.e. rely on existing code to route the NMI to the correct domain. On nested VM-Exit, reverse the process and set/clear V_NMI_PENDING for L1 based one whether nmi_pending is zero or non-zero. There is no need to consider vmcb02 in this case, as V_NMI_PENDING can be set in vmcb02 if vNMI is disabled for L2, and if vNMI is enabled for L2, then L1 and L2 have different NMI contexts. Co-developed-by: Maxim Levitsky <[email protected]> Signed-off-by: Maxim Levitsky <[email protected]> Signed-off-by: Santosh Shukla <[email protected]> Link: https://lore.kernel.org/r/[email protected] [sean: massage changelog to match the code] Signed-off-by: Sean Christopherson <[email protected]>
2023-03-22KVM: x86: Add support for SVM's Virtual NMISantosh Shukla2-21/+115
Add support for SVM's Virtual NMIs implementation, which adds proper tracking of virtual NMI blocking, and an intr_ctrl flag that software can set to mark a virtual NMI as pending. Pending virtual NMIs are serviced by hardware if/when virtual NMIs become unblocked, i.e. act more or less like real NMIs. Introduce two new kvm_x86_ops callbacks so to support SVM's vNMI, as KVM needs to treat a pending vNMI as partially injected. Specifically, if two NMIs (for L1) arrive concurrently in KVM's software model, KVM's ABI is to inject one and pend the other. Without vNMI, KVM manually tracks the pending NMI and uses NMI windows to detect when the NMI should be injected. With vNMI, the pending NMI is simply stuffed into the VMCB and handed off to hardware. This means that KVM needs to be able to set a vNMI pending on-demand, and also query if a vNMI is pending, e.g. to honor the "at most one NMI pending" rule and to preserve all NMIs across save and restore. Warn if KVM attempts to open an NMI window when vNMI is fully enabled, as the above logic should prevent KVM from ever getting to kvm_check_and_inject_events() with two NMIs pending _in software_, and the "at most one NMI pending" logic should prevent having an NMI pending in hardware and an NMI pending in software if NMIs are also blocked, i.e. if KVM can't immediately inject the second NMI. Signed-off-by: Santosh Shukla <[email protected]> Co-developed-by: Maxim Levitsky <[email protected]> Signed-off-by: Maxim Levitsky <[email protected]> Link: https://lore.kernel.org/r/[email protected] [sean: rewrite shortlog and changelog, massage code comments] Signed-off-by: Sean Christopherson <[email protected]>
2023-03-22KVM: SVM: add wrappers to enable/disable IRET interceptionMaxim Levitsky1-9/+19
SEV-ES guests don't use IRET interception for the detection of an end of a NMI. Therefore it makes sense to create a wrapper to avoid repeating the check for the SEV-ES. No functional change is intended. Suggested-by: Sean Christopherson <[email protected]> Signed-off-by: Maxim Levitsky <[email protected]> [Renamed iret intercept API of style svm_{clr,set}_iret_intercept()] Signed-off-by: Santosh Shukla <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
2023-03-22KVM: nSVM: Raise event on nested VM exit if L1 doesn't intercept IRQsMaxim Levitsky1-0/+22
If L1 doesn't intercept interrupts, then KVM will use vmcb02's V_IRQ to detect an interrupt window for L1 IRQs. On a subsequent nested VM-Exit, KVM might need to copy the current V_IRQ from vmcb02 to vmcb01 to continue waiting for an interrupt window, i.e. if there is still a pending IRQ for L1. Raise KVM_REQ_EVENT on nested exit if L1 isn't intercepting IRQs to ensure that KVM will re-enable interrupt window detection if needed. Note that this is a theoretical bug because KVM already raises KVM_REQ_EVENT on each nested VM exit, because the nested VM exit resets RFLAGS and kvm_set_rflags() raises the KVM_REQ_EVENT unconditionally. Explicitly raise KVM_REQ_EVENT for the interrupt window case to avoid having an unnecessary dependency on kvm_set_rflags(), and to document the scenario. Signed-off-by: Maxim Levitsky <[email protected]> [santosh: reworded description as per Sean's v2 comment] Signed-off-by: Santosh Shukla <[email protected]> Link: https://lore.kernel.org/r/[email protected] [sean: further massage changelog and comment] Signed-off-by: Sean Christopherson <[email protected]>
2023-03-22KVM: nSVM: Disable intercept of VINTR if saved L1 host RFLAGS.IF is 0Santosh Shukla2-5/+20
Disable intercept of virtual interrupts (used to detect interrupt windows) if the saved host (L1) RFLAGS.IF is '0', as the effective RFLAGS.IF for L1 interrupts will never be set while L2 is running (L2's RFLAGS.IF doesn't affect L1 IRQs when virtual interrupts are enabled). Suggested-by: Sean Christopherson <[email protected]> Link: https://lkml.kernel.org/r/Y9hybI65So5X2LFg%40google.com Signed-off-by: Santosh Shukla <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
2023-03-22KVM: nSVM: Don't sync vmcb02 V_IRQ back to vmcb12 if KVM (L0) is ↵Santosh Shukla1-11/+10
intercepting VINTR Don't sync vmcb02 V_IRQ back to vmcb12 if KVM (L0) is intercepting virtual interrupts in order to request an interrupt window, as KVM has usurped vmcb02's int_ctl. If an interrupt window opens before the next VM-Exit, svm_clear_vintr() will restore vmcb12's int_ctl. If no window opens, V_IRQ will be correctly preserved in vmcb12's int_ctl (because it was never recognized while L2 was running). Suggested-by: Sean Christopherson <[email protected]> Link: https://lkml.kernel.org/r/Y9hybI65So5X2LFg%40google.com Signed-off-by: Santosh Shukla <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
2023-03-22KVM: SVM: Use kvm_is_cr4_bit_set() to query SMAP/SMEP in "can emulate"Binbin Wu1-4/+2
Use kvm_is_cr4_bit_set() to query SMAP and SMEP when determining whether or not AMD's SMAP+SEV errata prevents KVM from emulating an instruction. This eliminates an implicit cast from ulong to bool and makes the code slightly more readable. Note, any overhead from making multiple calls to kvm_read_cr4_bits() is negligible, not to mention the code is question is encountered only in rare situations, i.e. is not a remotely hot path. Suggested-by: Sean Christopherson <[email protected]> Signed-off-by: Binbin Wu <[email protected]> Link: https://lore.kernel.org/r/[email protected] [sean: keep local smap/smep variables, massage changelog] Signed-off-by: Sean Christopherson <[email protected]>
2023-03-22KVM: x86: Use boolean return value for is_{pae,pse,paging}()Binbin Wu1-1/+1
Convert is_{pae,pse,paging}() to use kvm_is_cr{0,4}_bit_set() and return bools. Returning an "int" requires not one, but two implicit casts, first from "unsigned long" to "int", and then again to a "bool". Both casts are more than a bit dangerous; the ulong=>int casts would drop a bit on 64-bit kernels _if_ the bits in question weren't in the lower 32 bits, and the int=>bool cast can result in false negatives/positives, e.g. see commit 0c928ff26bd6 ("KVM: SVM: Fix benign "bool vs. int" comparison in svm_set_cr0()"). Suggested-by: Sean Christopherson <[email protected]> Signed-off-by: Binbin Wu <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
2023-03-22KVM: SVM: Fix benign "bool vs. int" comparison in svm_set_cr0()Sean Christopherson1-1/+1
Explicitly convert the return from is_paging() to a bool when comparing against old_paging, which is also a boolean. is_paging() sneakily uses kvm_read_cr0_bits() and returns an int, i.e. returns X86_CR0_PG or 0, not 1 or 0. Luckily, the bug is benign as it only results in a false positive, not a false negative, i.e. only causes a spurious refresh of CR4 when paging is enabled in both the old and new. Cc: Maxim Levitsky <[email protected]> Fixes: c53bbe2145f5 ("KVM: x86: SVM: don't passthrough SMAP/SMEP/PKE bits in !NPT && !gCR0.PG case") Signed-off-by: Sean Christopherson <[email protected]>
2023-03-17crypto: ccp - Add a header for multiple drivers to use `__psp_pa`Mario Limonciello1-0/+1
The TEE subdriver for CCP, the amdtee driver and the i2c-designware-amdpsp drivers all include `psp-sev.h` even though they don't use SEV functionality. Move the definition of `__psp_pa` into a common header to be included by all of these drivers. Reviewed-by: Jan Dabros <[email protected]> Acked-by: Jarkko Nikula <[email protected]> # For the drivers/i2c/busses/i2c-designware-amdpsp.c Acked-by: Sumit Garg <[email protected]> # For TEE subsystem bits Acked-by: Tom Lendacky <[email protected]> Acked-by: Sean Christopherson <[email protected]> # KVM Signed-off-by: Mario Limonciello <[email protected]> Signed-off-by: Herbert Xu <[email protected]>
2023-03-16kvm: svm: Add IA32_FLUSH_CMD guest supportEmanuele Giuseppe Esposito1-13/+30
Expose IA32_FLUSH_CMD to the guest if the guest CPUID enumerates support for this MSR. As with IA32_PRED_CMD, permission for unintercepted writes to this MSR will be granted to the guest after the first non-zero write. Signed-off-by: Emanuele Giuseppe Esposito <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-03-14KVM: SVM: WARN if GATag generation drops VM or vCPU ID informationSean Christopherson1-3/+12
WARN if generating a GATag given a VM ID and vCPU ID doesn't yield the same IDs when pulling the IDs back out of the tag. Don't bother adding error handling to callers, this is very much a paranoid sanity check as KVM fully controls the VM ID and is supposed to reject too-big vCPU IDs. Signed-off-by: Sean Christopherson <[email protected]> Reviewed-by: Suravee Suthikulpanit <[email protected]> Tested-by: Suravee Suthikulpanit <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-03-14KVM: SVM: Modify AVIC GATag to support max number of 512 vCPUsSuravee Suthikulpanit1-8/+18
Define AVIC_VCPU_ID_MASK based on AVIC_PHYSICAL_MAX_INDEX, i.e. the mask that effectively controls the largest guest physical APIC ID supported by x2AVIC, instead of hardcoding the number of bits to 8 (and the number of VM bits to 24). The AVIC GATag is programmed into the AMD IOMMU IRTE to provide a reference back to KVM in case the IOMMU cannot inject an interrupt into a non-running vCPU. In such a case, the IOMMU notifies software by creating a GALog entry with the corresponded GATag, and KVM then uses the GATag to find the correct VM+vCPU to kick. Dropping bit 8 from the GATag results in kicking the wrong vCPU when targeting vCPUs with x2APIC ID > 255. Fixes: 4d1d7942e36a ("KVM: SVM: Introduce logic to (de)activate x2AVIC mode") Cc: [email protected] Reported-by: Alejandro Jimenez <[email protected]> Signed-off-by: Suravee Suthikulpanit <[email protected]> Co-developed-by: Sean Christopherson <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Reviewed-by: Suravee Suthikulpanit <[email protected]> Tested-by: Suravee Suthikulpanit <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-02-25Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds8-288/+300
Pull kvm updates from Paolo Bonzini: "ARM: - Provide a virtual cache topology to the guest to avoid inconsistencies with migration on heterogenous systems. Non secure software has no practical need to traverse the caches by set/way in the first place - Add support for taking stage-2 access faults in parallel. This was an accidental omission in the original parallel faults implementation, but should provide a marginal improvement to machines w/o FEAT_HAFDBS (such as hardware from the fruit company) - A preamble to adding support for nested virtualization to KVM, including vEL2 register state, rudimentary nested exception handling and masking unsupported features for nested guests - Fixes to the PSCI relay that avoid an unexpected host SVE trap when resuming a CPU when running pKVM - VGIC maintenance interrupt support for the AIC - Improvements to the arch timer emulation, primarily aimed at reducing the trap overhead of running nested - Add CONFIG_USERFAULTFD to the KVM selftests config fragment in the interest of CI systems - Avoid VM-wide stop-the-world operations when a vCPU accesses its own redistributor - Serialize when toggling CPACR_EL1.SMEN to avoid unexpected exceptions in the host - Aesthetic and comment/kerneldoc fixes - Drop the vestiges of the old Columbia mailing list and add [Oliver] as co-maintainer RISC-V: - Fix wrong usage of PGDIR_SIZE instead of PUD_SIZE - Correctly place the guest in S-mode after redirecting a trap to the guest - Redirect illegal instruction traps to guest - SBI PMU support for guest s390: - Sort out confusion between virtual and physical addresses, which currently are the same on s390 - A new ioctl that performs cmpxchg on guest memory - A few fixes x86: - Change tdp_mmu to a read-only parameter - Separate TDP and shadow MMU page fault paths - Enable Hyper-V invariant TSC control - Fix a variety of APICv and AVIC bugs, some of them real-world, some of them affecting architecurally legal but unlikely to happen in practice - Mark APIC timer as expired if its in one-shot mode and the count underflows while the vCPU task was being migrated - Advertise support for Intel's new fast REP string features - Fix a double-shootdown issue in the emergency reboot code - Ensure GIF=1 and disable SVM during an emergency reboot, i.e. give SVM similar treatment to VMX - Update Xen's TSC info CPUID sub-leaves as appropriate - Add support for Hyper-V's extended hypercalls, where "support" at this point is just forwarding the hypercalls to userspace - Clean up the kvm->lock vs. kvm->srcu sequences when updating the PMU and MSR filters - One-off fixes and cleanups - Fix and cleanup the range-based TLB flushing code, used when KVM is running on Hyper-V - Add support for filtering PMU events using a mask. If userspace wants to restrict heavily what events the guest can use, it can now do so without needing an absurd number of filter entries - Clean up KVM's handling of "PMU MSRs to save", especially when vPMU support is disabled - Add PEBS support for Intel Sapphire Rapids - Fix a mostly benign overflow bug in SEV's send|receive_update_data() - Move several SVM-specific flags into vcpu_svm x86 Intel: - Handle NMI VM-Exits before leaving the noinstr region - A few trivial cleanups in the VM-Enter flows - Stop enabling VMFUNC for L1 purely to document that KVM doesn't support EPTP switching (or any other VM function) for L1 - Fix a crash when using eVMCS's enlighted MSR bitmaps Generic: - Clean up the hardware enable and initialization flow, which was scattered around multiple arch-specific hooks. Instead, just let the arch code call into generic code. Both x86 and ARM should benefit from not having to fight common KVM code's notion of how to do initialization - Account allocations in generic kvm_arch_alloc_vm() - Fix a memory leak if coalesced MMIO unregistration fails selftests: - On x86, cache the CPU vendor (AMD vs. Intel) and use the info to emit the correct hypercall instruction instead of relying on KVM to patch in VMMCALL - Use TAP interface for kvm_binary_stats_test and tsc_msrs_test" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (325 commits) KVM: SVM: hyper-v: placate modpost section mismatch error KVM: x86/mmu: Make tdp_mmu_allowed static KVM: arm64: nv: Use reg_to_encoding() to get sysreg ID KVM: arm64: nv: Only toggle cache for virtual EL2 when SCTLR_EL2 changes KVM: arm64: nv: Filter out unsupported features from ID regs KVM: arm64: nv: Emulate EL12 register accesses from the virtual EL2 KVM: arm64: nv: Allow a sysreg to be hidden from userspace only KVM: arm64: nv: Emulate PSTATE.M for a guest hypervisor KVM: arm64: nv: Add accessors for SPSR_EL1, ELR_EL1 and VBAR_EL1 from virtual EL2 KVM: arm64: nv: Handle SMCs taken from virtual EL2 KVM: arm64: nv: Handle trapped ERET from virtual EL2 KVM: arm64: nv: Inject HVC exceptions to the virtual EL2 KVM: arm64: nv: Support virtual EL2 exceptions KVM: arm64: nv: Handle HCR_EL2.NV system register traps KVM: arm64: nv: Add nested virt VCPU primitives for vEL2 VCPU state KVM: arm64: nv: Add EL2 system registers to vcpu context KVM: arm64: nv: Allow userspace to set PSR_MODE_EL2x KVM: arm64: nv: Reset VCPU to EL2 registers if VCPU nested virt is set KVM: arm64: nv: Introduce nested virtualization VCPU feature KVM: arm64: Use the S2 MMU context to iterate over S2 table ...
2023-02-22KVM: SVM: hyper-v: placate modpost section mismatch errorRandy Dunlap1-2/+2
modpost reports section mismatch errors/warnings: WARNING: modpost: vmlinux.o: section mismatch in reference: svm_hv_hardware_setup (section: .text) -> (unknown) (section: .init.data) WARNING: modpost: vmlinux.o: section mismatch in reference: svm_hv_hardware_setup (section: .text) -> (unknown) (section: .init.data) WARNING: modpost: vmlinux.o: section mismatch in reference: svm_hv_hardware_setup (section: .text) -> (unknown) (section: .init.data) This "(unknown) (section: .init.data)" all refer to svm_x86_ops. Tag svm_hv_hardware_setup() with __init to fix a modpost warning as the non-stub implementation accesses __initdata (svm_x86_ops), i.e. would generate a use-after-free if svm_hv_hardware_setup() were actually invoked post-init. The helper is only called from svm_hardware_setup(), which is also __init, i.e. lack of __init is benign other than the modpost warning. Fixes: 1e0c7d40758b ("KVM: SVM: hyper-v: Remote TLB flush for SVM") Signed-off-by: Randy Dunlap <[email protected]> Cc: Vineeth Pillai <[email protected]> Cc: Paolo Bonzini <[email protected]> Cc: [email protected] Cc: [email protected] Reviewed-by: Sean Christopherson <[email protected]> Reviewed-by: Vitaly Kuznetsov <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-02-21Merge tag 'x86_cpu_for_v6.3_rc1' of ↵Linus Torvalds1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpuid updates from Borislav Petkov: - Cache the AMD debug registers in per-CPU variables to avoid MSR writes where possible, when supporting a debug registers swap feature for SEV-ES guests - Add support for AMD's version of eIBRS called Automatic IBRS which is a set-and-forget control of indirect branch restriction speculation resources on privilege change - Add support for a new x86 instruction - LKGS - Load kernel GS which is part of the FRED infrastructure - Reset SPEC_CTRL upon init to accomodate use cases like kexec which rediscover - Other smaller fixes and cleanups * tag 'x86_cpu_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/amd: Cache debug register values in percpu variables KVM: x86: Propagate the AMD Automatic IBRS feature to the guest x86/cpu: Support AMD Automatic IBRS x86/cpu, kvm: Add the SMM_CTL MSR not present feature x86/cpu, kvm: Add the Null Selector Clears Base feature x86/cpu, kvm: Move X86_FEATURE_LFENCE_RDTSC to its native leaf x86/cpu, kvm: Add the NO_NESTED_DATA_BP feature KVM: x86: Move open-coded CPUID leaf 0x80000021 EAX bit propagation code x86/cpu, kvm: Add support for CPUID_80000021_EAX x86/gsseg: Add the new <asm/gsseg.h> header to <asm/asm-prototypes.h> x86/gsseg: Use the LKGS instruction if available for load_gs_index() x86/gsseg: Move load_gs_index() to its own new header file x86/gsseg: Make asm_load_gs_index() take an u16 x86/opcode: Add the LKGS instruction to x86-opcode-map x86/cpufeature: Add the CPU feature bit for LKGS x86/bugs: Reset speculation control settings on init x86/cpu: Remove redundant extern x86_read_arch_cap_msr()
2023-02-15Merge tag 'kvm-x86-svm-6.3' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini5-23/+44
KVM SVM changes for 6.3: - Fix a mostly benign overflow bug in SEV's send|receive_update_data() - Move the SVM-specific "host flags" into vcpu_svm (extracted from the vNMI enabling series) - A handful for fixes and cleanups
2023-02-07KVM: SVM: Fix potential overflow in SEV's send|receive_update_data()Peter Gonda1-2/+2
KVM_SEV_SEND_UPDATE_DATA and KVM_SEV_RECEIVE_UPDATE_DATA have an integer overflow issue. Params.guest_len and offset are both 32 bits wide, with a large params.guest_len the check to confirm a page boundary is not crossed can falsely pass: /* Check if we are crossing the page boundary * offset = params.guest_uaddr & (PAGE_SIZE - 1); if ((params.guest_len + offset > PAGE_SIZE)) Add an additional check to confirm that params.guest_len itself is not greater than PAGE_SIZE. Note, this isn't a security concern as overflow can happen if and only if params.guest_len is greater than 0xfffff000, and the FW spec says these commands fail with lengths greater than 16KB, i.e. the PSP will detect KVM's goof. Fixes: 15fb7de1a7f5 ("KVM: SVM: Add KVM_SEV_RECEIVE_UPDATE_DATA command") Fixes: d3d1af85e2c7 ("KVM: SVM: Add KVM_SEND_UPDATE_DATA command") Reported-by: Andy Nguyen <[email protected]> Suggested-by: Thomas Lendacky <[email protected]> Signed-off-by: Peter Gonda <[email protected]> Cc: David Rientjes <[email protected]> Cc: Paolo Bonzini <[email protected]> Cc: Sean Christopherson <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Reviewed-by: Tom Lendacky <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
2023-01-31KVM: x86: Move HF_NMI_MASK and HF_IRET_MASK into "struct vcpu_svm"Maxim Levitsky2-9/+31
Move HF_NMI_MASK and HF_IRET_MASK (a.k.a. "waiting for IRET") out of the common "hflags" and into dedicated flags in "struct vcpu_svm". The flags are used only for the SVM and thus should not be in hflags. Tracking NMI masking in software isn't SVM specific, e.g. VMX has a similar flag (soft_vnmi_blocked), but that's much more of a hack as VMX can't intercept IRET, is useful only for ancient CPUs, i.e. will hopefully be removed at some point, and again the exact behavior is vendor specific and shouldn't ever be referenced in common code. converting VMX No functional change is intended. Suggested-by: Sean Christopherson <[email protected]> Signed-off-by: Maxim Levitsky <[email protected]> Tested-by: Santosh Shukla <[email protected]> Link: https://lore.kernel.org/r/[email protected] [sean: split from HF_GIF_MASK patch] Signed-off-by: Sean Christopherson <[email protected]>
2023-01-31KVM: x86: Move HF_GIF_MASK into "struct vcpu_svm" as "guest_gif"Maxim Levitsky1-3/+6
Move HF_GIF_MASK out of the common "hflags" and into vcpu_svm.guest_gif. GIF is an SVM-only concept and has should never be consulted outside of SVM-specific code. No functional change is intended. Suggested-by: Sean Christopherson <[email protected]> Signed-off-by: Maxim Levitsky <[email protected]> Tested-by: Santosh Shukla <[email protected]> Link: https://lore.kernel.org/r/[email protected] [sean: split to separate patch] Signed-off-by: Sean Christopherson <[email protected]>
2023-01-31KVM: nSVM: Don't sync tlb_ctl back to vmcb12 on nested VM-ExitMaxim Levitsky1-1/+0
Don't sync the TLB control field from vmcb02 to vmcs12 on nested VM-Exit. Per AMD's APM, the field is not modified by hardware: The VMRUN instruction reads, but does not change, the value of the TLB_CONTROL field Signed-off-by: Maxim Levitsky <[email protected]> Tested-by: Santosh Shukla <[email protected]> Link: https://lore.kernel.org/r/[email protected] [sean: massage changelog] Signed-off-by: Sean Christopherson <[email protected]>
2023-01-26KVM: x86/pmu: Gate all "unimplemented MSR" prints on report_ignored_msrsSean Christopherson1-3/+2
Add helpers to print unimplemented MSR accesses and condition all such prints on report_ignored_msrs, i.e. honor userspace's request to not print unimplemented MSRs. Even though vcpu_unimpl() is ratelimited, printing can still be problematic, e.g. if a print gets stalled when host userspace is writing MSRs during live migration, an effective stall can result in very noticeable disruption in the guest. E.g. the profile below was taken while calling KVM_SET_MSRS on the PMU counters while the PMU was disabled in KVM. - 99.75% 0.00% [.] __ioctl - __ioctl - 99.74% entry_SYSCALL_64_after_hwframe do_syscall_64 sys_ioctl - do_vfs_ioctl - 92.48% kvm_vcpu_ioctl - kvm_arch_vcpu_ioctl - 85.12% kvm_set_msr_ignored_check svm_set_msr kvm_set_msr_common printk vprintk_func vprintk_default vprintk_emit console_unlock call_console_drivers univ8250_console_write serial8250_console_write uart_console_write Reported-by: Aaron Lewis <[email protected]> Reviewed-by: Vitaly Kuznetsov <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
2023-01-26KVM: x86/pmu: Cap kvm_pmu_cap.num_counters_gp at KVM's internal maxSean Christopherson1-0/+1
Limit kvm_pmu_cap.num_counters_gp during kvm_init_pmu_capability() based on the vendor PMU capabilities so that consuming num_counters_gp naturally does the right thing. This fixes a mostly theoretical bug where KVM could over-report its PMU support in KVM_GET_SUPPORTED_CPUID for leaf 0xA, e.g. if the number of counters reported by perf is greater than KVM's hardcoded internal limit. Incorporating input from the AMD PMU also avoids over-reporting MSRs to save when running on AMD. Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
2023-01-25KVM: x86: Propagate the AMD Automatic IBRS feature to the guestKim Phillips1-0/+3
Add the AMD Automatic IBRS feature bit to those being propagated to the guest, and enable the guest EFER bit. Signed-off-by: Kim Phillips <[email protected]> Signed-off-by: Borislav Petkov (AMD) <[email protected]> Acked-by: Sean Christopherson <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2023-01-24KVM: SVM: Account scratch allocations used to decrypt SEV guest memoryAnish Ghulati1-1/+1
Account the temp/scratch allocation used to decrypt unaligned debug accesses to SEV guest memory, the allocation is very much tied to the target VM. Reported-by: Mingwei Zhang <[email protected]> Signed-off-by: Anish Ghulati <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
2023-01-24KVM: svm/avic: Drop "struct kvm_x86_ops" for avic_hardware_setup()Like Xu3-3/+3
Even in commit 4bdec12aa8d6 ("KVM: SVM: Detect X2APIC virtualization (x2AVIC) support"), where avic_hardware_setup() was first introduced, its only pass-in parameter "struct kvm_x86_ops *ops" is not used at all. Clean it up a bit to avoid compiler ranting from LLVM toolchain. Signed-off-by: Like Xu <[email protected]> Reviewed-by: Sean Christopherson <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
2023-01-24KVM: SVM: remove redundant ret variablezhang songyi1-5/+2
Return value from svm_nmi_blocked() directly instead of taking this in another redundant variable. Signed-off-by: zhang songyi <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
2023-01-24KVM: x86/pmu: Correct the mask used in a pmu event filter lookupAaron Lewis1-0/+1
When checking if a pmu event the guest is attempting to program should be filtered, only consider the event select + unit mask in that decision. Use an architecture specific mask to mask out all other bits, including bits 35:32 on Intel. Those bits are not part of the event select and should not be considered in that decision. Fixes: 66bb8a065f5a ("KVM: x86: PMU Event Filter") Signed-off-by: Aaron Lewis <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sean Christopherson <[email protected]>
2023-01-24Merge branch 'kvm-lapic-fix-and-cleanup' into HEADPaolo Bonzini4-219/+188
The first half or so patches fix semi-urgent, real-world relevant APICv and AVIC bugs. The second half fixes a variety of AVIC and optimized APIC map bugs where KVM doesn't play nice with various edge cases that are architecturally legal(ish), but are unlikely to occur in most real world scenarios Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-24Merge branch 'kvm-v6.2-rc4-fixes' into HEADPaolo Bonzini1-7/+5
ARM: * Fix the PMCR_EL0 reset value after the PMU rework * Correctly handle S2 fault triggered by a S1 page table walk by not always classifying it as a write, as this breaks on R/O memslots * Document why we cannot exit with KVM_EXIT_MMIO when taking a write fault from a S1 PTW on a R/O memslot * Put the Apple M2 on the naughty list for not being able to correctly implement the vgic SEIS feature, just like the M1 before it * Reviewer updates: Alex is stepping down, replaced by Zenghui x86: * Fix various rare locking issues in Xen emulation and teach lockdep to detect them * Documentation improvements * Do not return host topology information from KVM_GET_SUPPORTED_CPUID
2023-01-13KVM: x86: Track required APICv inhibits with variable, not callbackSean Christopherson3-21/+16
Track the per-vendor required APICv inhibits with a variable instead of calling into vendor code every time KVM wants to query the set of required inhibits. The required inhibits are a property of the vendor's virtualization architecture, i.e. are 100% static. Using a variable allows the compiler to inline the check, e.g. generate a single-uop TEST+Jcc, and thus eliminates any desire to avoid checking inhibits for performance reasons. No functional change intended. Reviewed-by: Maxim Levitsky <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13Revert "KVM: SVM: Do not throw warning when calling avic_vcpu_load on a ↵Sean Christopherson1-0/+1
running vcpu" Turns out that some warnings exist for good reasons. Restore the warning in avic_vcpu_load() that guards against calling avic_vcpu_load() on a running vCPU now that KVM avoids doing so when switching between x2APIC and xAPIC. The entire point of the WARN is to highlight that KVM should not be reloading an AVIC. Opportunistically convert the WARN_ON() to WARN_ON_ONCE() to avoid spamming the kernel if it does fire. This reverts commit c0caeee65af3944b7b8abbf566e7cc1fae15c775. Reviewed-by: Maxim Levitsky <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: SVM: Ignore writes to Remote Read Data on AVIC write trapsSean Christopherson1-0/+3
Drop writes to APIC_RRR, a.k.a. Remote Read Data Register, on AVIC unaccelerated write traps. The register is read-only and isn't emulated by KVM. Sending the register through kvm_apic_write_nodecode() will result in screaming when x2APIC is enabled due to the unexpected failure to retrieve the MSR (KVM expects that only "legal" accesses will trap). Fixes: 4d1d7942e36a ("KVM: SVM: Introduce logic to (de)activate x2AVIC mode") Signed-off-by: Sean Christopherson <[email protected]> Reviewed-by: Maxim Levitsky <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: SVM: Handle multiple logical targets in AVIC kick fastpathSean Christopherson1-48/+62
Iterate over all target logical IDs in the AVIC kick fastpath instead of bailing if there is more than one target. Now that KVM inhibits AVIC if vCPUs aren't mapped 1:1 with logical IDs, each bit in the destination is guaranteed to match to at most one vCPU, i.e. iterating over the bitmap is guaranteed to kick each valid target exactly once. Reviewed-by: Maxim Levitsky <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: SVM: Require logical ID to be power-of-2 for AVIC entrySean Christopherson1-15/+15
Do not modify AVIC's logical ID table if the logical ID portion of the LDR is not a power-of-2, i.e. if the LDR has multiple bits set. Taking only the first bit means that KVM will fail to match MDAs that intersect with "higher" bits in the "ID" The "ID" acts as a bitmap, but is referred to as an ID because there's an implicit, unenforced "requirement" that software only set one bit. This edge case is arguably out-of-spec behavior, but KVM cleanly handles it in all other cases, e.g. the optimized logical map (and AVIC!) is also disabled in this scenario. Refactor the code to consolidate the checks, and so that the code looks more like avic_kick_target_vcpus_fast(). Fixes: 18f40c53e10f ("svm: Add VMEXIT handlers for AVIC") Cc: Suravee Suthikulpanit <[email protected]> Cc: Maxim Levitsky <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: SVM: Update svm->ldr_reg cache even if LDR is "bad"Sean Christopherson1-10/+4
Update SVM's cache of the LDR even if the new value is "bad". Leaving stale information in the cache can result in KVM missing updates and/or invalidating the wrong entry, e.g. if avic_invalidate_logical_id_entry() is triggered after a different vCPU has "claimed" the old LDR. Fixes: 18f40c53e10f ("svm: Add VMEXIT handlers for AVIC") Reviewed-by: Maxim Levitsky <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: SVM: Always update local APIC on writes to logical dest registerSean Christopherson1-7/+4
Update the vCPU's local (virtual) APIC on LDR writes even if the write "fails". The APIC needs to recalc the optimized logical map even if the LDR is invalid or zero, e.g. if the guest clears its LDR, the optimized map will be left as is and the vCPU will receive interrupts using its old LDR. Fixes: 18f40c53e10f ("svm: Add VMEXIT handlers for AVIC") Reviewed-by: Maxim Levitsky <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: SVM: Inhibit AVIC if vCPUs are aliased in logical modeSean Christopherson1-1/+2
Inhibit SVM's AVIC if multiple vCPUs are aliased to the same logical ID. Architecturally, all CPUs whose logical ID matches the MDA are supposed to receive the interrupt; overwriting existing entries in AVIC's logical=>physical map can result in missed IPIs. Fixes: 18f40c53e10f ("svm: Add VMEXIT handlers for AVIC") Reviewed-by: Maxim Levitsky <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: x86: Inhibit APICv/AVIC if the optimized physical map is disabledSean Christopherson1-0/+1
Inhibit APICv/AVIC if the optimized physical map is disabled so that KVM KVM provides consistent APIC behavior if xAPIC IDs are aliased due to vcpu_id being truncated and the x2APIC hotplug hack isn't enabled. If the hotplug hack is disabled, events that are emulated by KVM will follow architectural behavior (all matching vCPUs receive events, even if the "match" is due to truncation), whereas APICv and AVIC will deliver events only to the first matching vCPU, i.e. the vCPU that matches without truncation. Note, the "extra" inhibit is needed because KVM deliberately ignores mismatches due to truncation when applying the APIC_ID_MODIFIED inhibit so that large VMs (>255 vCPUs) can run with APICv/AVIC. Reviewed-by: Maxim Levitsky <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: SVM: Add helper to perform final AVIC "kick" of single vCPUSean Christopherson1-12/+13
Add a helper to perform the final kick, two instances of the ICR decoding is one too many. No functional change intended. Signed-off-by: Sean Christopherson <[email protected]> Reviewed-by: Maxim Levitsky <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: SVM: Document that vCPU ID == APIC ID in AVIC kick fastpatchSean Christopherson1-3/+7
Document that AVIC is inhibited if any vCPU's APIC ID diverges from its vCPU ID, i.e. that there's no need to check for a destination match in the AVIC kick fast path. Opportunistically tweak comments to remove "guest bug", as that suggests KVM is punting on error handling, which is not the case. Targeting a non-existent vCPU or no vCPUs _may_ be a guest software bug, but whether or not it's a guest bug is irrelevant. Such behavior is architecturally legal and thus needs to faithfully emulated by KVM (and it is). Signed-off-by: Sean Christopherson <[email protected]> Reviewed-by: Maxim Levitsky <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13Revert "KVM: SVM: Use target APIC ID to complete x2AVIC IRQs when possible"Sean Christopherson1-18/+11
Due to a likely mismerge of patches, KVM ended up with a superfluous commit to "enable" AVIC's fast path for x2AVIC mode. Even worse, the superfluous commit has several bugs and creates a nasty local shadow variable. Rather than fix the bugs piece-by-piece[*] to achieve the same end result, revert the patch wholesale. Opportunistically add a comment documenting the x2AVIC dependencies. This reverts commit 8c9e639da435874fb845c4d296ce55664071ea7a. [*] https://lore.kernel.org/all/[email protected] Fixes: 8c9e639da435 ("KVM: SVM: Use target APIC ID to complete x2AVIC IRQs when possible") Suggested-by: Maxim Levitsky <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: SVM: Fix x2APIC Logical ID calculation for avic_kick_target_vcpus_fastSuravee Suthikulpanit1-1/+1
For X2APIC ID in cluster mode, the logical ID is bit [15:0]. Fixes: 603ccef42ce9 ("KVM: x86: SVM: fix avic_kick_target_vcpus_fast") Cc: Maxim Levitsky <[email protected]> Signed-off-by: Suravee Suthikulpanit <[email protected]> Reviewed-by: Maxim Levitsky <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: SVM: Compute dest based on sender's x2APIC status for AVIC kickSean Christopherson1-7/+1
Compute the destination from ICRH using the sender's x2APIC status, not each (potential) target's x2APIC status. Fixes: c514d3a348ac ("KVM: SVM: Update avic_kick_target_vcpus to support 32-bit APIC ID") Cc: Li RongQing <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Reviewed-by: Li RongQing <[email protected]> Reviewed-by: Maxim Levitsky <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: SVM: Replace "avic_mode" enum with "x2avic_enabled" booleanSean Christopherson3-35/+24
Replace the "avic_mode" enum with a single bool to track whether or not x2AVIC is enabled. KVM already has "apicv_enabled" that tracks if any flavor of AVIC is enabled, i.e. AVIC_MODE_NONE and AVIC_MODE_X1 are redundant and unnecessary noise. No functional change intended. Signed-off-by: Sean Christopherson <[email protected]> Reviewed-by: Maxim Levitsky <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: x86: Inhibit APIC memslot if x2APIC and AVIC are enabledSean Christopherson3-7/+9
Free the APIC access page memslot if any vCPU enables x2APIC and SVM's AVIC is enabled to prevent accesses to the virtual APIC on vCPUs with x2APIC enabled. On AMD, if its "hybrid" mode is enabled (AVIC is enabled when x2APIC is enabled even without x2AVIC support), keeping the APIC access page memslot results in the guest being able to access the virtual APIC page as x2APIC is fully emulated by KVM. I.e. hardware isn't aware that the guest is operating in x2APIC mode. Exempt nested SVM's update of APICv state from the new logic as x2APIC can't be toggled on VM-Exit. In practice, invoking the x2APIC logic should be harmless precisely because it should be a glorified nop, but play it safe to avoid latent bugs, e.g. with dropping the vCPU's SRCU lock. Intel doesn't suffer from the same issue as APICv has fully independent VMCS controls for xAPIC vs. x2APIC virtualization. Technically, KVM should provide bus error semantics and not memory semantics for the APIC page when x2APIC is enabled, but KVM already provides memory semantics in other scenarios, e.g. if APICv/AVIC is enabled and the APIC is hardware disabled (via APIC_BASE MSR). Note, checking apic_access_memslot_enabled without taking locks relies it being set during vCPU creation (before kvm_vcpu_reset()). vCPUs can race to set the inhibit and delete the memslot, i.e. can get false positives, but can't get false negatives as apic_access_memslot_enabled can't be toggled "on" once any vCPU reaches KVM_RUN. Opportunistically drop the "can" while updating avic_activate_vmcb()'s comment, i.e. to state that KVM _does_ support the hybrid mode. Move the "Note:" down a line to conform to preferred kernel/KVM multi-line comment style. Opportunistically update the apicv_update_lock comment, as it isn't actually used to protect apic_access_memslot_enabled (which is protected by slots_lock). Fixes: 0e311d33bfbe ("KVM: SVM: Introduce hybrid-AVIC mode") Signed-off-by: Sean Christopherson <[email protected]> Reviewed-by: Maxim Levitsky <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: x86: Move APIC access page helper to common x86 codeSean Christopherson1-34/+7
Move the APIC access page allocation helper function to common x86 code, the allocation routine is virtually identical between APICv (VMX) and AVIC (SVM). Keep APICv's gfn_to_page() + put_page() sequence, which verifies that a backing page can be allocated, i.e. that the system isn't under heavy memory pressure. Forcing the backing page to be populated isn't strictly necessary, but skipping the effective prefetch only delays the inevitable. Reviewed-by: Maxim Levitsky <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: SVM: Don't put/load AVIC when setting virtual APIC modeSean Christopherson3-18/+17
Move the VMCB updates from avic_refresh_apicv_exec_ctrl() into avic_set_virtual_apic_mode() and invert the dependency being said functions to avoid calling avic_vcpu_{load,put}() and avic_set_pi_irte_mode() when "only" setting the virtual APIC mode. avic_set_virtual_apic_mode() is invoked from common x86 with preemption enabled, which makes avic_vcpu_{load,put}() unhappy. Luckily, calling those and updating IRTE stuff is unnecessary as the only reason avic_set_virtual_apic_mode() is called is to handle transitions between xAPIC and x2APIC that don't also toggle APICv activation. And if activation doesn't change, there's no need to fiddle with the physical APIC ID table or update IRTE. The "full" refresh is guaranteed to be called if activation changes in this case as the only call to the "set" path is: kvm_vcpu_update_apicv(vcpu); static_call_cond(kvm_x86_set_virtual_apic_mode)(vcpu); and kvm_vcpu_update_apicv() invokes the refresh if activation changes: if (apic->apicv_active == activate) goto out; apic->apicv_active = activate; kvm_apic_update_apicv(vcpu); static_call(kvm_x86_refresh_apicv_exec_ctrl)(vcpu); Rename the helper to reflect that it is also called during "refresh". WARNING: CPU: 183 PID: 49186 at arch/x86/kvm/svm/avic.c:1081 avic_vcpu_put+0xde/0xf0 [kvm_amd] CPU: 183 PID: 49186 Comm: stable Tainted: G O 6.0.0-smp--fcddbca45f0a-sink #34 Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 10.48.0 01/27/2022 RIP: 0010:avic_vcpu_put+0xde/0xf0 [kvm_amd] avic_refresh_apicv_exec_ctrl+0x142/0x1c0 [kvm_amd] avic_set_virtual_apic_mode+0x5a/0x70 [kvm_amd] kvm_lapic_set_base+0x149/0x1a0 [kvm] kvm_set_apic_base+0x8f/0xd0 [kvm] kvm_set_msr_common+0xa3a/0xdc0 [kvm] svm_set_msr+0x364/0x6b0 [kvm_amd] __kvm_set_msr+0xb8/0x1c0 [kvm] kvm_emulate_wrmsr+0x58/0x1d0 [kvm] msr_interception+0x1c/0x30 [kvm_amd] svm_invoke_exit_handler+0x31/0x100 [kvm_amd] svm_handle_exit+0xfc/0x160 [kvm_amd] vcpu_enter_guest+0x21bb/0x23e0 [kvm] vcpu_run+0x92/0x450 [kvm] kvm_arch_vcpu_ioctl_run+0x43e/0x6e0 [kvm] kvm_vcpu_ioctl+0x559/0x620 [kvm] Fixes: 05c4fe8c1bd9 ("KVM: SVM: Refresh AVIC configuration when changing APIC mode") Cc: [email protected] Cc: Suravee Suthikulpanit <[email protected]> Reviewed-by: Maxim Levitsky <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2023-01-13KVM: SVM: Process ICR on AVIC IPI delivery failure due to invalid targetSean Christopherson1-7/+9
Emulate ICR writes on AVIC IPI failures due to invalid targets using the same logic as failures due to invalid types. AVIC acceleration fails if _any_ of the targets are invalid, and crucially VM-Exits before sending IPIs to targets that _are_ valid. In logical mode, the destination is a bitmap, i.e. a single IPI can target multiple logical IDs. Doing nothing causes KVM to drop IPIs if at least one target is valid and at least one target is invalid. Fixes: 18f40c53e10f ("svm: Add VMEXIT handlers for AVIC") Cc: [email protected] Reviewed-by: Paolo Bonzini <[email protected]> Reviewed-by: Maxim Levitsky <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>