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15 hoursMerge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Paolo Bonzini: "Many patches, pretty much all of them small, that accumulated while I was on vacation. ARM: - Remove the last leftovers of the ill-fated FPSIMD host state mapping at EL2 stage-1 - Fix unexpected advertisement to the guest of unimplemented S2 base granule sizes - Gracefully fail initialising pKVM if the interrupt controller isn't GICv3 - Also gracefully fail initialising pKVM if the carveout allocation fails - Fix the computing of the minimum MMIO range required for the host on stage-2 fault - Fix the generation of the GICv3 Maintenance Interrupt in nested mode x86: - Reject SEV{-ES} intra-host migration if one or more vCPUs are actively being created, so as not to create a non-SEV{-ES} vCPU in an SEV{-ES} VM - Use a pre-allocated, per-vCPU buffer for handling de-sparsification of vCPU masks in Hyper-V hypercalls; fixes a "stack frame too large" issue - Allow out-of-range/invalid Xen event channel ports when configuring IRQ routing, to avoid dictating a specific ioctl() ordering to userspace - Conditionally reschedule when setting memory attributes to avoid soft lockups when userspace converts huge swaths of memory to/from private - Add back MWAIT as a required feature for the MONITOR/MWAIT selftest - Add a missing field in struct sev_data_snp_launch_start that resulted in the guest-visible workarounds field being filled at the wrong offset - Skip non-canonical address when processing Hyper-V PV TLB flushes to avoid VM-Fail on INVVPID - Advertise supported TDX TDVMCALLs to userspace - Pass SetupEventNotifyInterrupt arguments to userspace - Fix TSC frequency underflow" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: avoid underflow when scaling TSC frequency KVM: arm64: Remove kvm_arch_vcpu_run_map_fp() KVM: arm64: Fix handling of FEAT_GTG for unimplemented granule sizes KVM: arm64: Don't free hyp pages with pKVM on GICv2 KVM: arm64: Fix error path in init_hyp_mode() KVM: arm64: Adjust range correctly during host stage-2 faults KVM: arm64: nv: Fix MI line level calculation in vgic_v3_nested_update_mi() KVM: x86/hyper-v: Skip non-canonical addresses during PV TLB flush KVM: SVM: Add missing member in SNP_LAUNCH_START command structure Documentation: KVM: Fix unexpected unindent warnings KVM: selftests: Add back the missing check of MONITOR/MWAIT availability KVM: Allow CPU to reschedule while setting per-page memory attributes KVM: x86/xen: Allow 'out of range' event channel ports in IRQ routing table. KVM: x86/hyper-v: Use preallocated per-vCPU buffer for de-sparsified vCPU masks KVM: SVM: Initialize vmsa_pa in VMCB to INVALID_PAGE if VMSA page is NULL KVM: SVM: Reject SEV{-ES} intra host migration if vCPU creation is in-flight KVM: TDX: Report supported optional TDVMCALLs in TDX capabilities KVM: TDX: Exit to userspace for SetupEventNotifyInterrupt
38 hoursKVM: x86: avoid underflow when scaling TSC frequencyPaolo Bonzini
In function kvm_guest_time_update(), __scale_tsc() is used to calculate a TSC *frequency* rather than a TSC value. With low-enough ratios, a TSC value that is less than 1 would underflow to 0 and to an infinite while loop in kvm_get_time_scale(): kvm_guest_time_update(struct kvm_vcpu *v) if (kvm_caps.has_tsc_control) tgt_tsc_khz = kvm_scale_tsc(tgt_tsc_khz, v->arch.l1_tsc_scaling_ratio); __scale_tsc(u64 ratio, u64 tsc) ratio=122380531, tsc=2299998, N=48 ratio*tsc >> N = 0.999... -> 0 Later in the function: Call Trace: <TASK> kvm_get_time_scale arch/x86/kvm/x86.c:2458 [inline] kvm_guest_time_update+0x926/0xb00 arch/x86/kvm/x86.c:3268 vcpu_enter_guest.constprop.0+0x1e70/0x3cf0 arch/x86/kvm/x86.c:10678 vcpu_run+0x129/0x8d0 arch/x86/kvm/x86.c:11126 kvm_arch_vcpu_ioctl_run+0x37a/0x13d0 arch/x86/kvm/x86.c:11352 kvm_vcpu_ioctl+0x56b/0xe60 virt/kvm/kvm_main.c:4188 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0x12d/0x190 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x59/0x110 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x78/0xe2 This can really happen only when fuzzing, since the TSC frequency would have to be nonsensically low. Fixes: 35181e86df97 ("KVM: x86: Add a common TSC scaling function") Reported-by: Yuntao Liu <liuyuntao12@huawei.com> Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
3 daysMerge tag 'tsa_x86_bugs_for_6.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull CPU speculation fixes from Borislav Petkov: "Add the mitigation logic for Transient Scheduler Attacks (TSA) TSA are new aspeculative side channel attacks related to the execution timing of instructions under specific microarchitectural conditions. In some cases, an attacker may be able to use this timing information to infer data from other contexts, resulting in information leakage. Add the usual controls of the mitigation and integrate it into the existing speculation bugs infrastructure in the kernel" * tag 'tsa_x86_bugs_for_6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/process: Move the buffer clearing before MONITOR x86/microcode/AMD: Add TSA microcode SHAs KVM: SVM: Advertise TSA CPUID bits to guests x86/bugs: Add a Transient Scheduler Attacks mitigation x86/bugs: Rename MDS machinery to something more generic
12 daysMerge tag 'x86_urgent_for_v6.16_rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: - Make sure DR6 and DR7 are initialized to their architectural values and not accidentally cleared, leading to misconfigurations * tag 'x86_urgent_for_v6.16_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/traps: Initialize DR7 by writing its architectural reset value x86/traps: Initialize DR6 by writing its architectural reset value
2025-06-25KVM: x86/hyper-v: Skip non-canonical addresses during PV TLB flushManuel Andreas
In KVM guests with Hyper-V hypercalls enabled, the hypercalls HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST and HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX allow a guest to request invalidation of portions of a virtual TLB. For this, the hypercall parameter includes a list of GVAs that are supposed to be invalidated. However, when non-canonical GVAs are passed, there is currently no filtering in place and they are eventually passed to checked invocations of INVVPID on Intel / INVLPGA on AMD. While AMD's INVLPGA silently ignores non-canonical addresses (effectively a no-op), Intel's INVVPID explicitly signals VM-Fail and ultimately triggers the WARN_ONCE in invvpid_error(): invvpid failed: ext=0x0 vpid=1 gva=0xaaaaaaaaaaaaa000 WARNING: CPU: 6 PID: 326 at arch/x86/kvm/vmx/vmx.c:482 invvpid_error+0x91/0xa0 [kvm_intel] Modules linked in: kvm_intel kvm 9pnet_virtio irqbypass fuse CPU: 6 UID: 0 PID: 326 Comm: kvm-vm Not tainted 6.15.0 #14 PREEMPT(voluntary) RIP: 0010:invvpid_error+0x91/0xa0 [kvm_intel] Call Trace: vmx_flush_tlb_gva+0x320/0x490 [kvm_intel] kvm_hv_vcpu_flush_tlb+0x24f/0x4f0 [kvm] kvm_arch_vcpu_ioctl_run+0x3013/0x5810 [kvm] Hyper-V documents that invalid GVAs (those that are beyond a partition's GVA space) are to be ignored. While not completely clear whether this ruling also applies to non-canonical GVAs, it is likely fine to make that assumption, and manual testing on Azure confirms "real" Hyper-V interprets the specification in the same way. Skip non-canonical GVAs when processing the list of address to avoid tripping the INVVPID failure. Alternatively, KVM could filter out "bad" GVAs before inserting into the FIFO, but practically speaking the only downside of pushing validation to the final processing is that doing so is suboptimal for the guest, and no well-behaved guest will request TLB flushes for non-canonical addresses. Fixes: 260970862c88 ("KVM: x86: hyper-v: Handle HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST{,EX} calls gently") Cc: stable@vger.kernel.org Signed-off-by: Manuel Andreas <manuel.andreas@tum.de> Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Link: https://lore.kernel.org/r/c090efb3-ef82-499f-a5e0-360fc8420fb7@tum.de Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-06-24x86/traps: Initialize DR7 by writing its architectural reset valueXin Li (Intel)
Initialize DR7 by writing its architectural reset value to always set bit 10, which is reserved to '1', when "clearing" DR7 so as not to trigger unanticipated behavior if said bit is ever unreserved, e.g. as a feature enabling flag with inverted polarity. Signed-off-by: Xin Li (Intel) <xin@zytor.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: H. Peter Anvin (Intel) <hpa@zytor.com> Reviewed-by: Sohil Mehta <sohil.mehta@intel.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Sean Christopherson <seanjc@google.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Cc:stable@vger.kernel.org Link: https://lore.kernel.org/all/20250620231504.2676902-3-xin%40zytor.com
2025-06-24KVM: x86/xen: Allow 'out of range' event channel ports in IRQ routing table.David Woodhouse
To avoid imposing an ordering constraint on userspace, allow 'invalid' event channel targets to be configured in the IRQ routing table. This is the same as accepting interrupts targeted at vCPUs which don't exist yet, which is already the case for both Xen event channels *and* for MSIs (which don't do any filtering of permitted APIC ID targets at all). If userspace actually *triggers* an IRQ with an invalid target, that will fail cleanly, as kvm_xen_set_evtchn_fast() also does the same range check. If KVM enforced that the IRQ target must be valid at the time it is *configured*, that would force userspace to create all vCPUs and do various other parts of setup (in this case, setting the Xen long_mode) before restoring the IRQ table. Cc: stable@vger.kernel.org Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Paul Durrant <paul@xen.org> Link: https://lore.kernel.org/r/e489252745ac4b53f1f7f50570b03fb416aa2065.camel@infradead.org [sean: massage comment] Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-06-24KVM: x86/hyper-v: Use preallocated per-vCPU buffer for de-sparsified vCPU masksSean Christopherson
Use a preallocated per-vCPU bitmap for tracking the unpacked set of vCPUs being targeted for Hyper-V's paravirt TLB flushing. If KVM_MAX_NR_VCPUS is set to 4096 (which is allowed even for MAXSMP=n builds), putting the vCPU mask on-stack pushes kvm_hv_flush_tlb() past the default FRAME_WARN limit. arch/x86/kvm/hyperv.c:2001:12: error: stack frame size (1288) exceeds limit (1024) in 'kvm_hv_flush_tlb' [-Werror,-Wframe-larger-than] 2001 | static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc) | ^ 1 error generated. Note, sparse_banks was given the same treatment by commit 7d5e88d301f8 ("KVM: x86: hyper-v: Use preallocated buffer in 'struct kvm_vcpu_hv' instead of on-stack 'sparse_banks'"), for the exact same reason. Reported-by: Abinash Lalotra <abinashsinghlalotra@gmail.com> Closes: https://lore.kernel.org/all/20250613111023.786265-1-abinashsinghlalotra@gmail.com Link: https://lore.kernel.org/all/aEylI-O8kFnFHrOH@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-06-24KVM: SVM: Initialize vmsa_pa in VMCB to INVALID_PAGE if VMSA page is NULLSean Christopherson
When creating an SEV-ES vCPU for intra-host migration, set its vmsa_pa to INVALID_PAGE to harden against doing VMRUN with a bogus VMSA (KVM checks for a valid VMSA page in pre_sev_run()). Cc: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Liam Merwick <liam.merwick@oracle.com> Tested-by: Liam Merwick <liam.merwick@oracle.com> Link: https://lore.kernel.org/r/20250602224459.41505-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-06-24KVM: SVM: Reject SEV{-ES} intra host migration if vCPU creation is in-flightSean Christopherson
Reject migration of SEV{-ES} state if either the source or destination VM is actively creating a vCPU, i.e. if kvm_vm_ioctl_create_vcpu() is in the section between incrementing created_vcpus and online_vcpus. The bulk of vCPU creation runs _outside_ of kvm->lock to allow creating multiple vCPUs in parallel, and so sev_info.es_active can get toggled from false=>true in the destination VM after (or during) svm_vcpu_create(), resulting in an SEV{-ES} VM effectively having a non-SEV{-ES} vCPU. The issue manifests most visibly as a crash when trying to free a vCPU's NULL VMSA page in an SEV-ES VM, but any number of things can go wrong. BUG: unable to handle page fault for address: ffffebde00000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] SMP KASAN NOPTI CPU: 227 UID: 0 PID: 64063 Comm: syz.5.60023 Tainted: G U O 6.15.0-smp-DEV #2 NONE Tainted: [U]=USER, [O]=OOT_MODULE Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 12.52.0-0 10/28/2024 RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:206 [inline] RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:238 [inline] RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline] RIP: 0010:PageHead include/linux/page-flags.h:866 [inline] RIP: 0010:___free_pages+0x3e/0x120 mm/page_alloc.c:5067 Code: <49> f7 06 40 00 00 00 75 05 45 31 ff eb 0c 66 90 4c 89 f0 4c 39 f0 RSP: 0018:ffff8984551978d0 EFLAGS: 00010246 RAX: 0000777f80000001 RBX: 0000000000000000 RCX: ffffffff918aeb98 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffebde00000000 RBP: 0000000000000000 R08: ffffebde00000007 R09: 1ffffd7bc0000000 R10: dffffc0000000000 R11: fffff97bc0000001 R12: dffffc0000000000 R13: ffff8983e19751a8 R14: ffffebde00000000 R15: 1ffffd7bc0000000 FS: 0000000000000000(0000) GS:ffff89ee661d3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffebde00000000 CR3: 000000793ceaa000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000b5f DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: <TASK> sev_free_vcpu+0x413/0x630 arch/x86/kvm/svm/sev.c:3169 svm_vcpu_free+0x13a/0x2a0 arch/x86/kvm/svm/svm.c:1515 kvm_arch_vcpu_destroy+0x6a/0x1d0 arch/x86/kvm/x86.c:12396 kvm_vcpu_destroy virt/kvm/kvm_main.c:470 [inline] kvm_destroy_vcpus+0xd1/0x300 virt/kvm/kvm_main.c:490 kvm_arch_destroy_vm+0x636/0x820 arch/x86/kvm/x86.c:12895 kvm_put_kvm+0xb8e/0xfb0 virt/kvm/kvm_main.c:1310 kvm_vm_release+0x48/0x60 virt/kvm/kvm_main.c:1369 __fput+0x3e4/0x9e0 fs/file_table.c:465 task_work_run+0x1a9/0x220 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x7f0/0x25b0 kernel/exit.c:953 do_group_exit+0x203/0x2d0 kernel/exit.c:1102 get_signal+0x1357/0x1480 kernel/signal.c:3034 arch_do_signal_or_restart+0x40/0x690 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x67/0xb0 kernel/entry/common.c:218 do_syscall_64+0x7c/0x150 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f87a898e969 </TASK> Modules linked in: gq(O) gsmi: Log Shutdown Reason 0x03 CR2: ffffebde00000000 ---[ end trace 0000000000000000 ]--- Deliberately don't check for a NULL VMSA when freeing the vCPU, as crashing the host is likely desirable due to the VMSA being consumed by hardware. E.g. if KVM manages to allow VMRUN on the vCPU, hardware may read/write a bogus VMSA page. Accessing PFN 0 is "fine"-ish now that it's sequestered away thanks to L1TF, but panicking in this scenario is preferable to potentially running with corrupted state. Reported-by: Alexander Potapenko <glider@google.com> Tested-by: Alexander Potapenko <glider@google.com> Fixes: 0b020f5af092 ("KVM: SEV: Add support for SEV-ES intra host migration") Fixes: b56639318bb2 ("KVM: SEV: Add support for SEV intra host migration") Cc: stable@vger.kernel.org Cc: James Houghton <jthoughton@google.com> Cc: Peter Gonda <pgonda@google.com> Reviewed-by: Liam Merwick <liam.merwick@oracle.com> Tested-by: Liam Merwick <liam.merwick@oracle.com> Reviewed-by: James Houghton <jthoughton@google.com> Link: https://lore.kernel.org/r/20250602224459.41505-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-06-20KVM: TDX: Report supported optional TDVMCALLs in TDX capabilitiesPaolo Bonzini
Allow userspace to advertise TDG.VP.VMCALL subfunctions that the kernel also supports. For each output register of GetTdVmCallInfo's leaf 1, add two fields to KVM_TDX_CAPABILITIES: one for kernel-supported TDVMCALLs (userspace can set those blindly) and one for user-supported TDVMCALLs (userspace can set those if it knows how to handle them). Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-20KVM: TDX: Exit to userspace for SetupEventNotifyInterruptPaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-20KVM: TDX: Exit to userspace for GetTdVmCallInfoBinbin Wu
Exit to userspace for TDG.VP.VMCALL<GetTdVmCallInfo> via KVM_EXIT_TDX, to allow userspace to provide information about the support of TDVMCALLs when r12 is 1 for the TDVMCALLs beyond the GHCI base API. GHCI spec defines the GHCI base TDVMCALLs: <GetTdVmCallInfo>, <MapGPA>, <ReportFatalError>, <Instruction.CPUID>, <#VE.RequestMMIO>, <Instruction.HLT>, <Instruction.IO>, <Instruction.RDMSR> and <Instruction.WRMSR>. They must be supported by VMM to support TDX guests. For GetTdVmCallInfo - When leaf (r12) to enumerate TDVMCALL functionality is set to 0, successful execution indicates all GHCI base TDVMCALLs listed above are supported. Update the KVM TDX document with the set of the GHCI base APIs. - When leaf (r12) to enumerate TDVMCALL functionality is set to 1, it indicates the TDX guest is querying the supported TDVMCALLs beyond the GHCI base TDVMCALLs. Exit to userspace to let userspace set the TDVMCALL sub-function bit(s) accordingly to the leaf outputs. KVM could set the TDVMCALL bit(s) supported by itself when the TDVMCALLs don't need support from userspace after returning from userspace and before entering guest. Currently, no such TDVMCALLs implemented, KVM just sets the values returned from userspace. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com> [Adjust userspace API. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-20KVM: TDX: Handle TDG.VP.VMCALL<GetQuote>Binbin Wu
Handle TDVMCALL for GetQuote to generate a TD-Quote. GetQuote is a doorbell-like interface used by TDX guests to request VMM to generate a TD-Quote signed by a service hosting TD-Quoting Enclave operating on the host. A TDX guest passes a TD Report (TDREPORT_STRUCT) in a shared-memory area as parameter. Host VMM can access it and queue the operation for a service hosting TD-Quoting enclave. When completed, the Quote is returned via the same shared-memory area. KVM only checks the GPA from the TDX guest has the shared-bit set and drops the shared-bit before exiting to userspace to avoid bleeding the shared-bit into KVM's exit ABI. KVM forwards the request to userspace VMM (e.g. QEMU) and userspace VMM queues the operation asynchronously. KVM sets the return code according to the 'ret' field set by userspace to notify the TDX guest whether the request has been queued successfully or not. When the request has been queued successfully, the TDX guest can poll the status field in the shared-memory area to check whether the Quote generation is completed or not. When completed, the generated Quote is returned via the same buffer. Add KVM_EXIT_TDX as a new exit reason to userspace. Userspace is required to handle the KVM exit reason as the initial support for TDX, by reentering KVM to ensure that the TDVMCALL is complete. While at it, add a note that KVM_EXIT_HYPERCALL also requires reentry with KVM_RUN. Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com> Tested-by: Mikko Ylinen <mikko.ylinen@linux.intel.com> Acked-by: Kai Huang <kai.huang@intel.com> [Adjust userspace API. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-20KVM: TDX: Add new TDVMCALL status code for unsupported subfuncsBinbin Wu
Add the new TDVMCALL status code TDVMCALL_STATUS_SUBFUNC_UNSUPPORTED and return it for unimplemented TDVMCALL subfunctions. Returning TDVMCALL_STATUS_INVALID_OPERAND when a subfunction is not implemented is vague because TDX guests can't tell the error is due to the subfunction is not supported or an invalid input of the subfunction. New GHCI spec adds TDVMCALL_STATUS_SUBFUNC_UNSUPPORTED to avoid the ambiguity. Use it instead of TDVMCALL_STATUS_INVALID_OPERAND. Before the change, for common guest implementations, when a TDX guest receives TDVMCALL_STATUS_INVALID_OPERAND, it has two cases: 1. Some operand is invalid. It could change the operand to another value retry. 2. The subfunction is not supported. For case 1, an invalid operand usually means the guest implementation bug. Since the TDX guest can't tell which case is, the best practice for handling TDVMCALL_STATUS_INVALID_OPERAND is stopping calling such leaf, treating the failure as fatal if the TDVMCALL is essential or ignoring it if the TDVMCALL is optional. With this change, TDVMCALL_STATUS_SUBFUNC_UNSUPPORTED could be sent to old TDX guest that do not know about it, but it is expected that the guest will make the same action as TDVMCALL_STATUS_INVALID_OPERAND. Currently, no known TDX guest checks TDVMCALL_STATUS_INVALID_OPERAND specifically; for example Linux just checks for success. Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com> [Return it for untrapped KVM_HC_MAP_GPA_RANGE. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-17KVM: SVM: Advertise TSA CPUID bits to guestsBorislav Petkov (AMD)
Synthesize the TSA CPUID feature bits for guests. Set TSA_{SQ,L1}_NO on unaffected machines. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2025-06-17x86/bugs: Add a Transient Scheduler Attacks mitigationBorislav Petkov (AMD)
Add the required features detection glue to bugs.c et all in order to support the TSA mitigation. Co-developed-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
2025-06-16x86/bugs: Rename MDS machinery to something more genericBorislav Petkov (AMD)
It will be used by other x86 mitigations. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
2025-06-12KVM: x86/mmu: Reject direct bits in gpa passed to KVM_PRE_FAULT_MEMORYPaolo Bonzini
Only let userspace pass the same addresses that were used in KVM_SET_USER_MEMORY_REGION (or KVM_SET_USER_MEMORY_REGION2); gpas in the the upper half of the address space are an implementation detail of TDX and KVM. Extracted from a patch by Sean Christopherson <seanjc@google.com>. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-12KVM: x86/mmu: Embed direct bits into gpa for KVM_PRE_FAULT_MEMORYPaolo Bonzini
Bug[*] reported for TDX case when enabling KVM_PRE_FAULT_MEMORY in QEMU. It turns out that @gpa passed to kvm_mmu_do_page_fault() doesn't have shared bit set when the memory attribute of it is shared, and it leads to wrong root in tdp_mmu_get_root_for_fault(). Fix it by embedding the direct bits in the gpa that is passed to kvm_tdp_map_page(), when the memory of the gpa is not private. [*] https://lore.kernel.org/qemu-devel/4a757796-11c2-47f1-ae0d-335626e818fd@intel.com/ Reported-by: Xiaoyao Li <xiaoyao.li@intel.com> Closes: https://lore.kernel.org/qemu-devel/4a757796-11c2-47f1-ae0d-335626e818fd@intel.com/ Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Message-ID: <20250611001018.2179964-1-xiaoyao.li@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-11KVM: SEV: Disable SEV-SNP support on initialization failureAshish Kalra
During platform init, SNP initialization may fail for several reasons, such as firmware command failures and incompatible versions. However, the KVM capability may continue to advertise support for it. The platform may have SNP enabled but if SNP_INIT fails then SNP is not supported by KVM. During KVM module initialization query the SNP platform status to obtain the SNP initialization state and use it as an additional condition to determine support for SEV-SNP. Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Co-developed-by: Pratik R. Sampat <prsampat@amd.com> Signed-off-by: Pratik R. Sampat <prsampat@amd.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com> Reviewed-by: Pavan Kumar Paluri <papaluri@amd.com> Message-ID: <20250512221634.12045-1-Ashish.Kalra@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-08treewide, timers: Rename from_timer() to timer_container_of()Ingo Molnar
Move this API to the canonical timer_*() namespace. [ tglx: Redone against pre rc1 ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com
2025-06-02Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull more kvm updates from Paolo Bonzini: Generic: - Clean up locking of all vCPUs for a VM by using the *_nest_lock() family of functions, and move duplicated code to virt/kvm/. kernel/ patches acked by Peter Zijlstra - Add MGLRU support to the access tracking perf test ARM fixes: - Make the irqbypass hooks resilient to changes in the GSI<->MSI routing, avoiding behind stale vLPI mappings being left behind. The fix is to resolve the VGIC IRQ using the host IRQ (which is stable) and nuking the vLPI mapping upon a routing change - Close another VGIC race where vCPU creation races with VGIC creation, leading to in-flight vCPUs entering the kernel w/o private IRQs allocated - Fix a build issue triggered by the recently added workaround for Ampere's AC04_CPU_23 erratum - Correctly sign-extend the VA when emulating a TLBI instruction potentially targeting a VNCR mapping - Avoid dereferencing a NULL pointer in the VGIC debug code, which can happen if the device doesn't have any mapping yet s390: - Fix interaction between some filesystems and Secure Execution - Some cleanups and refactorings, preparing for an upcoming big series x86: - Wait for target vCPU to ack KVM_REQ_UPDATE_PROTECTED_GUEST_STATE to fix a race between AP destroy and VMRUN - Decrypt and dump the VMSA in dump_vmcb() if debugging enabled for the VM - Refine and harden handling of spurious faults - Add support for ALLOWED_SEV_FEATURES - Add #VMGEXIT to the set of handlers special cased for CONFIG_RETPOLINE=y - Treat DEBUGCTL[5:2] as reserved to pave the way for virtualizing features that utilize those bits - Don't account temporary allocations in sev_send_update_data() - Add support for KVM_CAP_X86_BUS_LOCK_EXIT on SVM, via Bus Lock Threshold - Unify virtualization of IBRS on nested VM-Exit, and cross-vCPU IBPB, between SVM and VMX - Advertise support to userspace for WRMSRNS and PREFETCHI - Rescan I/O APIC routes after handling EOI that needed to be intercepted due to the old/previous routing, but not the new/current routing - Add a module param to control and enumerate support for device posted interrupts - Fix a potential overflow with nested virt on Intel systems running 32-bit kernels - Flush shadow VMCSes on emergency reboot - Add support for SNP to the various SEV selftests - Add a selftest to verify fastops instructions via forced emulation - Refine and optimize KVM's software processing of the posted interrupt bitmap, and share the harvesting code between KVM and the kernel's Posted MSI handler" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (93 commits) rtmutex_api: provide correct extern functions KVM: arm64: vgic-debug: Avoid dereferencing NULL ITE pointer KVM: arm64: vgic-init: Plug vCPU vs. VGIC creation race KVM: arm64: Unmap vLPIs affected by changes to GSI routing information KVM: arm64: Resolve vLPI by host IRQ in vgic_v4_unset_forwarding() KVM: arm64: Protect vLPI translation with vgic_irq::irq_lock KVM: arm64: Use lock guard in vgic_v4_set_forwarding() KVM: arm64: Mask out non-VA bits from TLBI VA* on VNCR invalidation arm64: sysreg: Drag linux/kconfig.h to work around vdso build issue KVM: s390: Simplify and move pv code KVM: s390: Refactor and split some gmap helpers KVM: s390: Remove unneeded srcu lock s390: Remove unneeded includes s390/uv: Improve splitting of large folios that cannot be split while dirty s390/uv: Always return 0 from s390_wiggle_split_folio() if successful s390/uv: Don't return 0 from make_hva_secure() if the operation was not successful rust: add helper for mutex_trylock RISC-V: KVM: use kvm_trylock_all_vcpus when locking all vCPUs KVM: arm64: use kvm_trylock_all_vcpus when locking all vCPUs x86: KVM: SVM: use kvm_lock_all_vcpus instead of a custom implementation ...
2025-05-29Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "As far as x86 goes this pull request "only" includes TDX host support. Quotes are appropriate because (at 6k lines and 100+ commits) it is much bigger than the rest, which will come later this week and consists mostly of bugfixes and selftests. s390 changes will also come in the second batch. ARM: - Add large stage-2 mapping (THP) support for non-protected guests when pKVM is enabled, clawing back some performance. - Enable nested virtualisation support on systems that support it, though it is disabled by default. - Add UBSAN support to the standalone EL2 object used in nVHE/hVHE and protected modes. - Large rework of the way KVM tracks architecture features and links them with the effects of control bits. While this has no functional impact, it ensures correctness of emulation (the data is automatically extracted from the published JSON files), and helps dealing with the evolution of the architecture. - Significant changes to the way pKVM tracks ownership of pages, avoiding page table walks by storing the state in the hypervisor's vmemmap. This in turn enables the THP support described above. - New selftest checking the pKVM ownership transition rules - Fixes for FEAT_MTE_ASYNC being accidentally advertised to guests even if the host didn't have it. - Fixes for the address translation emulation, which happened to be rather buggy in some specific contexts. - Fixes for the PMU emulation in NV contexts, decoupling PMCR_EL0.N from the number of counters exposed to a guest and addressing a number of issues in the process. - Add a new selftest for the SVE host state being corrupted by a guest. - Keep HCR_EL2.xMO set at all times for systems running with the kernel at EL2, ensuring that the window for interrupts is slightly bigger, and avoiding a pretty bad erratum on the AmpereOne HW. - Add workaround for AmpereOne's erratum AC04_CPU_23, which suffers from a pretty bad case of TLB corruption unless accesses to HCR_EL2 are heavily synchronised. - Add a per-VM, per-ITS debugfs entry to dump the state of the ITS tables in a human-friendly fashion. - and the usual random cleanups. LoongArch: - Don't flush tlb if the host supports hardware page table walks. - Add KVM selftests support. RISC-V: - Add vector registers to get-reg-list selftest - VCPU reset related improvements - Remove scounteren initialization from VCPU reset - Support VCPU reset from userspace using set_mpstate() ioctl x86: - Initial support for TDX in KVM. This finally makes it possible to use the TDX module to run confidential guests on Intel processors. This is quite a large series, including support for private page tables (managed by the TDX module and mirrored in KVM for efficiency), forwarding some TDVMCALLs to userspace, and handling several special VM exits from the TDX module. This has been in the works for literally years and it's not really possible to describe everything here, so I'll defer to the various merge commits up to and including commit 7bcf7246c42a ('Merge branch 'kvm-tdx-finish-initial' into HEAD')" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (248 commits) x86/tdx: mark tdh_vp_enter() as __flatten Documentation: virt/kvm: remove unreferenced footnote RISC-V: KVM: lock the correct mp_state during reset KVM: arm64: Fix documentation for vgic_its_iter_next() KVM: arm64: np-guest CMOs with PMD_SIZE fixmap KVM: arm64: Stage-2 huge mappings for np-guests KVM: arm64: Add a range to pkvm_mappings KVM: arm64: Convert pkvm_mappings to interval tree KVM: arm64: Add a range to __pkvm_host_test_clear_young_guest() KVM: arm64: Add a range to __pkvm_host_wrprotect_guest() KVM: arm64: Add a range to __pkvm_host_unshare_guest() KVM: arm64: Add a range to __pkvm_host_share_guest() KVM: arm64: Introduce for_each_hyp_page KVM: arm64: Handle huge mappings for np-guest CMOs KVM: arm64: nv: Release faulted-in VNCR page from mmu_lock critical section KVM: arm64: nv: Handle TLBI S1E2 for VNCR invalidation with mmu_lock held KVM: arm64: nv: Hold mmu_lock when invalidating VNCR SW-TLB before translating RISC-V: KVM: add KVM_CAP_RISCV_MP_STATE_RESET RISC-V: KVM: Remove scounteren initialization KVM: RISC-V: remove unnecessary SBI reset state ...
2025-05-28Merge branch 'kvm-lockdep-common' into HEADPaolo Bonzini
Introduce new mutex locking functions mutex_trylock_nest_lock() and mutex_lock_killable_nest_lock() and use them to clean up locking of all vCPUs for a VM. For x86, this removes some complex code that was used instead of lockdep's "nest_lock" feature. For ARM and RISC-V, this removes a lockdep warning when the VM is configured to have more than MAX_LOCK_DEPTH vCPUs, and removes a fair amount of duplicate code by sharing the logic across all architectures. Signed-off-by: Paolo BOnzini <pbonzini@redhat.com>
2025-05-27x86: KVM: SVM: use kvm_lock_all_vcpus instead of a custom implementationMaxim Levitsky
Use kvm_lock_all_vcpus instead of sev's own implementation. Because kvm_lock_all_vcpus uses the _nest_lock feature of lockdep, which ignores subclasses, there is no longer a need to use separate subclasses for source and target VMs. No functional change intended. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Message-ID: <20250512180407.659015-5-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-27Merge tag 'kvm-x86-svm-6.16' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini
KVM SVM changes for 6.16: - Wait for target vCPU to acknowledge KVM_REQ_UPDATE_PROTECTED_GUEST_STATE to fix a race between AP destroy and VMRUN. - Decrypt and dump the VMSA in dump_vmcb() if debugging enabled for the VM. - Add support for ALLOWED_SEV_FEATURES. - Add #VMGEXIT to the set of handlers special cased for CONFIG_RETPOLINE=y. - Treat DEBUGCTL[5:2] as reserved to pave the way for virtualizing features that utilize those bits. - Don't account temporary allocations in sev_send_update_data(). - Add support for KVM_CAP_X86_BUS_LOCK_EXIT on SVM, via Bus Lock Threshold.
2025-05-27Merge tag 'kvm-x86-vmx-6.16' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini
KVM VMX changes for 6.16: - Explicitly check MSR load/store list counts to fix a potential overflow on 32-bit kernels. - Flush shadow VMCSes on emergency reboot. - Revert mem_enc_ioctl() back to an optional hook, as it's nullified when SEV or TDX is disabled via Kconfig. - Macrofy the handling of vt_x86_ops to eliminate a pile of boilerplate code needed for TDX, and to optimize CONFIG_KVM_INTEL_TDX=n builds.
2025-05-27Merge tag 'kvm-x86-pir-6.16' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini
KVM x86 posted interrupt changes for 6.16: Refine and optimize KVM's software processing of the PIR, and ultimately share PIR harvesting code between KVM and the kernel's Posted MSI handler
2025-05-27Merge tag 'kvm-x86-mmu-6.16' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini
KVM x86 MMU changes for 6.16: - Refine and harden handling of spurious faults. - Use kvm_x86_call() instead of open coding static_call().
2025-05-27Merge tag 'kvm-x86-misc-6.16' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini
KVM x86 misc changes for 6.16: - Unify virtualization of IBRS on nested VM-Exit, and cross-vCPU IBPB, between SVM and VMX. - Advertise support to userspace for WRMSRNS and PREFETCHI. - Rescan I/O APIC routes after handling EOI that needed to be intercepted due to the old/previous routing, but not the new/current routing. - Add a module param to control and enumerate support for device posted interrupts. - Misc cleanups.
2025-05-27KVM: VMX: use __always_inline for is_td_vcpu and is_tdEdward Adam Davis
is_td() and is_td_vcpu() are used in no-instrumentation sections; use __always_inline instead of inline. vmlinux.o: error: objtool: vmx_handle_nmi+0x47: call to is_td_vcpu.isra.0() leaves .noinstr.text section Fixes: 7172c753c26a ("KVM: VMX: Move common fields of struct vcpu_{vmx,tdx} to a struct") Signed-off-by: Edward Adam Davis <eadavis@qq.com> Message-ID: <tencent_1A767567C83C1137829622362E4A72756F09@qq.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-26Merge tag 'x86-core-2025-05-25' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core x86 updates from Ingo Molnar: "Boot code changes: - A large series of changes to reorganize the x86 boot code into a better isolated and easier to maintain base of PIC early startup code in arch/x86/boot/startup/, by Ard Biesheuvel. Motivation & background: | Since commit | | c88d71508e36 ("x86/boot/64: Rewrite startup_64() in C") | | dated Jun 6 2017, we have been using C code on the boot path in a way | that is not supported by the toolchain, i.e., to execute non-PIC C | code from a mapping of memory that is different from the one provided | to the linker. It should have been obvious at the time that this was a | bad idea, given the need to sprinkle fixup_pointer() calls left and | right to manipulate global variables (including non-pointer variables) | without crashing. | | This C startup code has been expanding, and in particular, the SEV-SNP | startup code has been expanding over the past couple of years, and | grown many of these warts, where the C code needs to use special | annotations or helpers to access global objects. This tree includes the first phase of this work-in-progress x86 boot code reorganization. Scalability enhancements and micro-optimizations: - Improve code-patching scalability (Eric Dumazet) - Remove MFENCEs for X86_BUG_CLFLUSH_MONITOR (Andrew Cooper) CPU features enumeration updates: - Thorough reorganization and cleanup of CPUID parsing APIs (Ahmed S. Darwish) - Fix, refactor and clean up the cacheinfo code (Ahmed S. Darwish, Thomas Gleixner) - Update CPUID bitfields to x86-cpuid-db v2.3 (Ahmed S. Darwish) Memory management changes: - Allow temporary MMs when IRQs are on (Andy Lutomirski) - Opt-in to IRQs-off activate_mm() (Andy Lutomirski) - Simplify choose_new_asid() and generate better code (Borislav Petkov) - Simplify 32-bit PAE page table handling (Dave Hansen) - Always use dynamic memory layout (Kirill A. Shutemov) - Make SPARSEMEM_VMEMMAP the only memory model (Kirill A. Shutemov) - Make 5-level paging support unconditional (Kirill A. Shutemov) - Stop prefetching current->mm->mmap_lock on page faults (Mateusz Guzik) - Predict valid_user_address() returning true (Mateusz Guzik) - Consolidate initmem_init() (Mike Rapoport) FPU support and vector computing: - Enable Intel APX support (Chang S. Bae) - Reorgnize and clean up the xstate code (Chang S. Bae) - Make task_struct::thread constant size (Ingo Molnar) - Restore fpu_thread_struct_whitelist() to fix CONFIG_HARDENED_USERCOPY=y (Kees Cook) - Simplify the switch_fpu_prepare() + switch_fpu_finish() logic (Oleg Nesterov) - Always preserve non-user xfeatures/flags in __state_perm (Sean Christopherson) Microcode loader changes: - Help users notice when running old Intel microcode (Dave Hansen) - AMD: Do not return error when microcode update is not necessary (Annie Li) - AMD: Clean the cache if update did not load microcode (Boris Ostrovsky) Code patching (alternatives) changes: - Simplify, reorganize and clean up the x86 text-patching code (Ingo Molnar) - Make smp_text_poke_batch_process() subsume smp_text_poke_batch_finish() (Nikolay Borisov) - Refactor the {,un}use_temporary_mm() code (Peter Zijlstra) Debugging support: - Add early IDT and GDT loading to debug relocate_kernel() bugs (David Woodhouse) - Print the reason for the last reset on modern AMD CPUs (Yazen Ghannam) - Add AMD Zen debugging document (Mario Limonciello) - Fix opcode map (!REX2) superscript tags (Masami Hiramatsu) - Stop decoding i64 instructions in x86-64 mode at opcode (Masami Hiramatsu) CPU bugs and bug mitigations: - Remove X86_BUG_MMIO_UNKNOWN (Borislav Petkov) - Fix SRSO reporting on Zen1/2 with SMT disabled (Borislav Petkov) - Restructure and harmonize the various CPU bug mitigation methods (David Kaplan) - Fix spectre_v2 mitigation default on Intel (Pawan Gupta) MSR API: - Large MSR code and API cleanup (Xin Li) - In-kernel MSR API type cleanups and renames (Ingo Molnar) PKEYS: - Simplify PKRU update in signal frame (Chang S. Bae) NMI handling code: - Clean up, refactor and simplify the NMI handling code (Sohil Mehta) - Improve NMI duration console printouts (Sohil Mehta) Paravirt guests interface: - Restrict PARAVIRT_XXL to 64-bit only (Kirill A. Shutemov) SEV support: - Share the sev_secrets_pa value again (Tom Lendacky) x86 platform changes: - Introduce the <asm/amd/> header namespace (Ingo Molnar) - i2c: piix4, x86/platform: Move the SB800 PIIX4 FCH definitions to <asm/amd/fch.h> (Mario Limonciello) Fixes and cleanups: - x86 assembly code cleanups and fixes (Uros Bizjak) - Misc fixes and cleanups (Andi Kleen, Andy Lutomirski, Andy Shevchenko, Ard Biesheuvel, Bagas Sanjaya, Baoquan He, Borislav Petkov, Chang S. Bae, Chao Gao, Dan Williams, Dave Hansen, David Kaplan, David Woodhouse, Eric Biggers, Ingo Molnar, Josh Poimboeuf, Juergen Gross, Malaya Kumar Rout, Mario Limonciello, Nathan Chancellor, Oleg Nesterov, Pawan Gupta, Peter Zijlstra, Shivank Garg, Sohil Mehta, Thomas Gleixner, Uros Bizjak, Xin Li)" * tag 'x86-core-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (331 commits) x86/bugs: Fix spectre_v2 mitigation default on Intel x86/bugs: Restructure ITS mitigation x86/xen/msr: Fix uninitialized variable 'err' x86/msr: Remove a superfluous inclusion of <asm/asm.h> x86/paravirt: Restrict PARAVIRT_XXL to 64-bit only x86/mm/64: Make 5-level paging support unconditional x86/mm/64: Make SPARSEMEM_VMEMMAP the only memory model x86/mm/64: Always use dynamic memory layout x86/bugs: Fix indentation due to ITS merge x86/cpuid: Rename hypervisor_cpuid_base()/for_each_possible_hypervisor_cpuid_base() to cpuid_base_hypervisor()/for_each_possible_cpuid_base_hypervisor() x86/cpu/intel: Rename CPUID(0x2) descriptors iterator parameter x86/cacheinfo: Rename CPUID(0x2) descriptors iterator parameter x86/cpuid: Rename cpuid_get_leaf_0x2_regs() to cpuid_leaf_0x2() x86/cpuid: Rename have_cpuid_p() to cpuid_feature() x86/cpuid: Set <asm/cpuid/api.h> as the main CPUID header x86/cpuid: Move CPUID(0x2) APIs into <cpuid/api.h> x86/msr: Add rdmsrl_on_cpu() compatibility wrapper x86/mm: Fix kernel-doc descriptions of various pgtable methods x86/asm-offsets: Export certain 'struct cpuinfo_x86' fields for 64-bit asm use too x86/boot: Defer initialization of VM space related global variables ...
2025-05-26Merge tag 'v6.16-p1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto updates from Herbert Xu: "API: - Fix memcpy_sglist to handle partially overlapping SG lists - Use memcpy_sglist to replace null skcipher - Rename CRYPTO_TESTS to CRYPTO_BENCHMARK - Flip CRYPTO_MANAGER_DISABLE_TEST into CRYPTO_SELFTESTS - Hide CRYPTO_MANAGER - Add delayed freeing of driver crypto_alg structures Compression: - Allocate large buffers on first use instead of initialisation in scomp - Drop destination linearisation buffer in scomp - Move scomp stream allocation into acomp - Add acomp scatter-gather walker - Remove request chaining - Add optional async request allocation Hashing: - Remove request chaining - Add optional async request allocation - Move partial block handling into API - Add ahash support to hmac - Fix shash documentation to disallow usage in hard IRQs Algorithms: - Remove unnecessary SIMD fallback code on x86 and arm/arm64 - Drop avx10_256 xts(aes)/ctr(aes) on x86 - Improve avx-512 optimisations for xts(aes) - Move chacha arch implementations into lib/crypto - Move poly1305 into lib/crypto and drop unused Crypto API algorithm - Disable powerpc/poly1305 as it has no SIMD fallback - Move sha256 arch implementations into lib/crypto - Convert deflate to acomp - Set block size correctly in cbcmac Drivers: - Do not use sg_dma_len before mapping in sun8i-ss - Fix warm-reboot failure by making shutdown do more work in qat - Add locking in zynqmp-sha - Remove cavium/zip - Add support for PCI device 0x17D8 to ccp - Add qat_6xxx support in qat - Add support for RK3576 in rockchip-rng - Add support for i.MX8QM in caam Others: - Fix irq_fpu_usable/kernel_fpu_begin inconsistency during CPU bring-up - Add new SEV/SNP platform shutdown API in ccp" * tag 'v6.16-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (382 commits) x86/fpu: Fix irq_fpu_usable() to return false during CPU onlining crypto: qat - add missing header inclusion crypto: api - Redo lookup on EEXIST Revert "crypto: testmgr - Add hash export format testing" crypto: marvell/cesa - Do not chain submitted requests crypto: powerpc/poly1305 - add depends on BROKEN for now Revert "crypto: powerpc/poly1305 - Add SIMD fallback" crypto: ccp - Add missing tee info reg for teev2 crypto: ccp - Add missing bootloader info reg for pspv5 crypto: sun8i-ce - move fallback ahash_request to the end of the struct crypto: octeontx2 - Use dynamic allocated memory region for lmtst crypto: octeontx2 - Initialize cptlfs device info once crypto: xts - Only add ecb if it is not already there crypto: lrw - Only add ecb if it is not already there crypto: testmgr - Add hash export format testing crypto: testmgr - Use ahash for generic tfm crypto: hmac - Add ahash support crypto: testmgr - Ignore EEXIST on shash allocation crypto: algapi - Add driver template support to crypto_inst_setname crypto: shash - Set reqsize in shash_alg ...
2025-05-26Merge tag 'loongarch-kvm-6.16' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson into HEAD LoongArch KVM changes for v6.16 1. Don't flush tlb if HW PTW supported. 2. Add LoongArch KVM selftests support.
2025-05-19KVM: SVM: Add support for KVM_CAP_X86_BUS_LOCK_EXIT on SVM CPUsManali Shukla
Add support for KVM_CAP_X86_BUS_LOCK_EXIT on SVM CPUs with Bus Lock Threshold, which is close enough to VMX's Bus Lock Detection VM-Exit to allow reusing KVM_CAP_X86_BUS_LOCK_EXIT. The biggest difference between the two features is that Threshold is fault-like, whereas Detection is trap-like. To allow the guest to make forward progress, Threshold provides a per-VMCB counter which is decremented every time a bus lock occurs, and a VM-Exit is triggered if and only if the counter is '0'. To provide Detection-like semantics, initialize the counter to '0', i.e. exit on every bus lock, and when re-executing the guilty instruction, set the counter to '1' to effectively step past the instruction. Note, in the unlikely scenario that re-executing the instruction doesn't trigger a bus lock, e.g. because the guest has changed memory types or patched the guilty instruction, the bus lock counter will be left at '1', i.e. the guest will be able to do a bus lock on a different instruction. In a perfect world, KVM would ensure the counter is '0' if the guest has made forward progress, e.g. if RIP has changed. But trying to close that hole would incur non-trivial complexity, for marginal benefit; the intent of KVM_CAP_X86_BUS_LOCK_EXIT is to allow userspace rate-limit bus locks, not to allow for precise detection of problematic guest code. And, it's simply not feasible to fully close the hole, e.g. if an interrupt arrives before the original instruction can re-execute, the guest could step past a different bus lock. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Manali Shukla <manali.shukla@amd.com> Link: https://lore.kernel.org/r/20250502050346.14274-5-manali.shukla@amd.com [sean: fix typo in comment] Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-05-16KVM: x86/mmu: Use kvm_x86_call() instead of manual static_call()Sean Christopherson
Use KVM's preferred kvm_x86_call() wrapper to invoke static calls related to mirror page tables. No functional change intended. Fixes: 77ac7079e66d ("KVM: x86/tdp_mmu: Propagate building mirror page tables") Fixes: 94faba8999b9 ("KVM: x86/tdp_mmu: Propagate tearing down mirror page tables") Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://lore.kernel.org/r/20250331182703.725214-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-05-16KVM: x86: Make kvm_pio_request.linear_rip a common field for user exitsManali Shukla
Move and rename kvm_pio_request.linear_rip to kvm_vcpu_arch.cui_linear_rip so that the field can be used by other userspace exit completion flows that need to take action if and only if userspace has not modified RIP. No functional changes intended. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Manali Shukla <manali.shukla@amd.com> Link: https://lore.kernel.org/r/20250502050346.14274-2-manali.shukla@amd.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-05-16x86/cpuid: Rename ↵Ahmed S. Darwish
hypervisor_cpuid_base()/for_each_possible_hypervisor_cpuid_base() to cpuid_base_hypervisor()/for_each_possible_cpuid_base_hypervisor() In order to let all the APIs under <cpuid/api.h> have a shared "cpuid_" namespace, rename hypervisor_cpuid_base() to cpuid_base_hypervisor(). To align with the new style, also rename: for_each_possible_hypervisor_cpuid_base(function) to: for_each_possible_cpuid_base_hypervisor(function) Adjust call-sites accordingly. Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: x86-cpuid@lists.linux.dev Link: https://lore.kernel.org/r/aCZOi0Oohc7DpgTo@lx-t490
2025-05-15x86/cpuid: Set <asm/cpuid/api.h> as the main CPUID headerAhmed S. Darwish
The main CPUID header <asm/cpuid.h> was originally a storefront for the headers: <asm/cpuid/api.h> <asm/cpuid/leaf_0x2_api.h> Now that the latter CPUID(0x2) header has been merged into the former, there is no practical difference between <asm/cpuid.h> and <asm/cpuid/api.h>. Migrate all users to the <asm/cpuid/api.h> header, in preparation of the removal of <asm/cpuid.h>. Don't remove <asm/cpuid.h> just yet, in case some new code in -next started using it. Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: x86-cpuid@lists.linux.dev Link: https://lore.kernel.org/r/20250508150240.172915-3-darwi@linutronix.de
2025-05-13Merge commit 'its-for-linus-20250509-merge' into x86/core, to resolve conflictsIngo Molnar
Conflicts: Documentation/admin-guide/hw-vuln/index.rst arch/x86/include/asm/cpufeatures.h arch/x86/kernel/alternative.c arch/x86/kernel/cpu/bugs.c arch/x86/kernel/cpu/common.c drivers/base/cpu.c include/linux/cpu.h Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-05-13Merge branch 'x86/msr' into x86/core, to resolve conflictsIngo Molnar
Conflicts: arch/x86/boot/startup/sme.c arch/x86/coco/sev/core.c arch/x86/kernel/fpu/core.c arch/x86/kernel/fpu/xstate.c Semantic conflict: arch/x86/include/asm/sev-internal.h Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-05-13Merge branch 'x86/bugs' into x86/core, to merge dependent commitsIngo Molnar
Prepare to resolve conflicts with an upstream series of fixes that conflict with pending x86 changes: 6f5bf947bab0 Merge tag 'its-for-linus-20250509' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-05-11Merge tag 'its-for-linus-20250509' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 ITS mitigation from Dave Hansen: "Mitigate Indirect Target Selection (ITS) issue. I'd describe this one as a good old CPU bug where the behavior is _obviously_ wrong, but since it just results in bad predictions it wasn't wrong enough to notice. Well, the researchers noticed and also realized that thus bug undermined a bunch of existing indirect branch mitigations. Thus the unusually wide impact on this one. Details: ITS is a bug in some Intel CPUs that affects indirect branches including RETs in the first half of a cacheline. Due to ITS such branches may get wrongly predicted to a target of (direct or indirect) branch that is located in the second half of a cacheline. Researchers at VUSec found this behavior and reported to Intel. Affected processors: - Cascade Lake, Cooper Lake, Whiskey Lake V, Coffee Lake R, Comet Lake, Ice Lake, Tiger Lake and Rocket Lake. Scope of impact: - Guest/host isolation: When eIBRS is used for guest/host isolation, the indirect branches in the VMM may still be predicted with targets corresponding to direct branches in the guest. - Intra-mode using cBPF: cBPF can be used to poison the branch history to exploit ITS. Realigning the indirect branches and RETs mitigates this attack vector. - User/kernel: With eIBRS enabled user/kernel isolation is *not* impacted by ITS. - Indirect Branch Prediction Barrier (IBPB): Due to this bug indirect branches may be predicted with targets corresponding to direct branches which were executed prior to IBPB. This will be fixed in the microcode. Mitigation: As indirect branches in the first half of cacheline are affected, the mitigation is to replace those indirect branches with a call to thunk that is aligned to the second half of the cacheline. RETs that take prediction from RSB are not affected, but they may be affected by RSB-underflow condition. So, RETs in the first half of cacheline are also patched to a return thunk that executes the RET aligned to second half of cacheline" * tag 'its-for-linus-20250509' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: selftest/x86/bugs: Add selftests for ITS x86/its: FineIBT-paranoid vs ITS x86/its: Use dynamic thunks for indirect branches x86/ibt: Keep IBT disabled during alternative patching mm/execmem: Unify early execmem_cache behaviour x86/its: Align RETs in BHB clear sequence to avoid thunking x86/its: Add support for RSB stuffing mitigation x86/its: Add "vmexit" option to skip mitigation on some CPUs x86/its: Enable Indirect Target Selection mitigation x86/its: Add support for ITS-safe return thunk x86/its: Add support for ITS-safe indirect thunk x86/its: Enumerate Indirect Target Selection (ITS) bug Documentation: x86/bugs/its: Add ITS documentation
2025-05-09x86/its: Enumerate Indirect Target Selection (ITS) bugPawan Gupta
ITS bug in some pre-Alderlake Intel CPUs may allow indirect branches in the first half of a cache line get predicted to a target of a branch located in the second half of the cache line. Set X86_BUG_ITS on affected CPUs. Mitigation to follow in later commits. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
2025-05-08KVM: SVM: Set/clear SRSO's BP_SPEC_REDUCE on 0 <=> 1 VM count transitionsSean Christopherson
Set the magic BP_SPEC_REDUCE bit to mitigate SRSO when running VMs if and only if KVM has at least one active VM. Leaving the bit set at all times unfortunately degrades performance by a wee bit more than expected. Use a dedicated spinlock and counter instead of hooking virtualization enablement, as changing the behavior of kvm.enable_virt_at_load based on SRSO_BP_SPEC_REDUCE is painful, and has its own drawbacks, e.g. could result in performance issues for flows that are sensitive to VM creation latency. Defer setting BP_SPEC_REDUCE until VMRUN is imminent to avoid impacting performance on CPUs that aren't running VMs, e.g. if a setup is using housekeeping CPUs. Setting BP_SPEC_REDUCE in task context, i.e. without blasting IPIs to all CPUs, also helps avoid serializing 1<=>N transitions without incurring a gross amount of complexity (see the Link for details on how ugly coordinating via IPIs gets). Link: https://lore.kernel.org/all/aBOnzNCngyS_pQIW@google.com Fixes: 8442df2b49ed ("x86/bugs: KVM: Add support for SRSO_MSR_FIX") Reported-by: Michael Larabel <Michael@michaellarabel.com> Closes: https://www.phoronix.com/review/linux-615-amd-regression Cc: Borislav Petkov <bp@alien8.de> Tested-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20250505180300.973137-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-05-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux v6.15-rc5Herbert Xu
Merge mainline to pick up bcachefs poly1305 patch 4bf4b5046de0 ("bcachefs: use library APIs for ChaCha20 and Poly1305"). This is a prerequisite for removing the poly1305 shash algorithm.
2025-05-02KVM: x86/mmu: Prevent installing hugepages when mem attributes are changingSean Christopherson
When changing memory attributes on a subset of a potential hugepage, add the hugepage to the invalidation range tracking to prevent installing a hugepage until the attributes are fully updated. Like the actual hugepage tracking updates in kvm_arch_post_set_memory_attributes(), process only the head and tail pages, as any potential hugepages that are entirely covered by the range will already be tracked. Note, only hugepage chunks whose current attributes are NOT mixed need to be added to the invalidation set, as mixed attributes already prevent installing a hugepage, and it's perfectly safe to install a smaller mapping for a gfn whose attributes aren't changing. Fixes: 8dd2eee9d526 ("KVM: x86/mmu: Handle page fault for private memory") Cc: stable@vger.kernel.org Reported-by: Michael Roth <michael.roth@amd.com> Tested-by: Michael Roth <michael.roth@amd.com> Link: https://lore.kernel.org/r/20250430220954.522672-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-05-02KVM: SVM: Update dump_ghcb() to use the GHCB snapshot fieldsTom Lendacky
Commit 4e15a0ddc3ff ("KVM: SEV: snapshot the GHCB before accessing it") updated the SEV code to take a snapshot of the GHCB before using it. But the dump_ghcb() function wasn't updated to use the snapshot locations. This results in incorrect output from dump_ghcb() for the "is_valid" and "valid_bitmap" fields. Update dump_ghcb() to use the proper locations. Fixes: 4e15a0ddc3ff ("KVM: SEV: snapshot the GHCB before accessing it") Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Liam Merwick <liam.merwick@oracle.com> Link: https://lore.kernel.org/r/8f03878443681496008b1b37b7c4bf77a342b459.1745866531.git.thomas.lendacky@amd.com [sean: add comment and snapshot qualifier] Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-05-02KVM: VMX: Clean up and macrofy x86_opsVishal Verma
Eliminate a lot of stub definitions by using macros to define the TDX vs non-TDX versions of various x86_ops. Moving the x86_ops wrappers under CONFIG_KVM_INTEL_TDX also allows nearly all of vmx/main.c to go under a single #ifdef, eliminating trampolines in the generated code, and almost all of the stubs. For example, with CONFIG_KVM_INTEL_TDX=n, before this cleanup, vt_refresh_apicv_exec_ctrl() would produce: 0000000000036490 <vt_refresh_apicv_exec_ctrl>: 36490: f3 0f 1e fa endbr64 36494: e8 00 00 00 00 call 36499 <vt_refresh_apicv_exec_ctrl+0x9> 36495: R_X86_64_PLT32 __fentry__-0x4 36499: e9 00 00 00 00 jmp 3649e <vt_refresh_apicv_exec_ctrl+0xe> 3649a: R_X86_64_PLT32 vmx_refresh_apicv_exec_ctrl-0x4 3649e: 66 90 xchg %ax,%ax After this patch, this is completely eliminated. Based on a patch by Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/kvm/Z6v9yjWLNTU6X90d@google.com/ Cc: Sean Christopherson <seanjc@google.com> Cc: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/20250318-vverma7-cleanup_x86_ops-v2-4-701e82d6b779@intel.com Signed-off-by: Sean Christopherson <seanjc@google.com>