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2022-05-25Merge tag 'kvmarm-5.19' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for 5.19 - Add support for the ARMv8.6 WFxT extension - Guard pages for the EL2 stacks - Trap and emulate AArch32 ID registers to hide unsupported features - Ability to select and save/restore the set of hypercalls exposed to the guest - Support for PSCI-initiated suspend in collaboration with userspace - GICv3 register-based LPI invalidation support - Move host PMU event merging into the vcpu data structure - GICv3 ITS save/restore fixes - The usual set of small-scale cleanups and fixes [Due to the conflict, KVM_SYSTEM_EVENT_SEV_TERM is relocated from 4 to 6. - Paolo]
2022-05-25KVM: selftests: x86: Fix test failure on arch lbr capable platformsYang Weijiang
On Arch LBR capable platforms, LBR_FMT in perf capability msr is 0x3f, so the last format test will fail. Use a true invalid format(0x30) for the test if it's running on these platforms. Opportunistically change the file name to reflect the tests actually carried out. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Yang Weijiang <weijiang.yang@intel.com> Message-Id: <20220512084046.105479-1-weijiang.yang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-25KVM: LAPIC: Trace LAPIC timer expiration on every vmentryWanpeng Li
In commit ec0671d5684a ("KVM: LAPIC: Delay trace_kvm_wait_lapic_expire tracepoint to after vmexit", 2019-06-04), trace_kvm_wait_lapic_expire was moved after guest_exit_irqoff() because invoking tracepoints within kvm_guest_enter/kvm_guest_exit caused a lockdep splat. These days this is not necessary, because commit 87fa7f3e98a1 ("x86/kvm: Move context tracking where it belongs", 2020-07-09) restricted the RCU extended quiescent state to be closer to vmentry/vmexit. Moving the tracepoint back to __kvm_wait_lapic_expire is more accurate, because it will be reported even if vcpu_enter_guest causes multiple vmentries via the IPI/Timer fast paths, and it allows the removal of advance_expire_delta. Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Message-Id: <1650961551-38390-1-git-send-email-wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-16Merge branch kvm-arm64/its-save-restore-fixes-5.19 into kvmarm-master/nextMarc Zyngier
* kvm-arm64/its-save-restore-fixes-5.19: : . : Tighten the ITS save/restore infrastructure to fail early rather : than late. Patches courtesy of Rocardo Koller. : . KVM: arm64: vgic: Undo work in failed ITS restores KVM: arm64: vgic: Do not ignore vgic_its_restore_cte failures KVM: arm64: vgic: Add more checks when restoring ITS tables KVM: arm64: vgic: Check that new ITEs could be saved in guest memory Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16Merge branch kvm-arm64/misc-5.19 into kvmarm-master/nextMarc Zyngier
* kvm-arm64/misc-5.19: : . : Misc fixes and general improvements for KVMM/arm64: : : - Better handle out of sequence sysregs in the global tables : : - Remove a couple of unnecessary loads from constant pool : : - Drop unnecessary pKVM checks : : - Add all known M1 implementations to the SEIS workaround : : - Cleanup kerneldoc warnings : . KVM: arm64: vgic-v3: List M1 Pro/Max as requiring the SEIS workaround KVM: arm64: pkvm: Don't mask already zeroed FEAT_SVE KVM: arm64: pkvm: Drop unnecessary FP/SIMD trap handler KVM: arm64: nvhe: Eliminate kernel-doc warnings KVM: arm64: Avoid unnecessary absolute addressing via literals KVM: arm64: Print emulated register table name when it is unsorted KVM: arm64: Don't BUG_ON() if emulated register table is unsorted Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16Merge branch kvm-arm64/per-vcpu-host-pmu-data into kvmarm-master/nextMarc Zyngier
* kvm-arm64/per-vcpu-host-pmu-data: : . : Pass the host PMU state in the vcpu to avoid the use of additional : shared memory between EL1 and EL2 (this obviously only applies : to nVHE and Protected setups). : : Patches courtesy of Fuad Tabba. : . KVM: arm64: pmu: Restore compilation when HW_PERF_EVENTS isn't selected KVM: arm64: Reenable pmu in Protected Mode KVM: arm64: Pass pmu events to hyp via vcpu KVM: arm64: Repack struct kvm_pmu to reduce size KVM: arm64: Wrapper for getting pmu_events Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16Merge branch kvm-arm64/vgic-invlpir into kvmarm-master/nextMarc Zyngier
* kvm-arm64/vgic-invlpir: : . : Implement MMIO-based LPI invalidation for vGICv3. : . KVM: arm64: vgic-v3: Advertise GICR_CTLR.{IR, CES} as a new GICD_IIDR revision KVM: arm64: vgic-v3: Implement MMIO-based LPI invalidation KVM: arm64: vgic-v3: Expose GICR_CTLR.RWP when disabling LPIs irqchip/gic-v3: Exposes bit values for GICR_CTLR.{IR, CES} Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16Merge branch kvm-arm64/psci-suspend into kvmarm-master/nextMarc Zyngier
* kvm-arm64/psci-suspend: : . : Add support for PSCI SYSTEM_SUSPEND and allow userspace to : filter the wake-up events. : : Patches courtesy of Oliver. : . Documentation: KVM: Fix title level for PSCI_SUSPEND selftests: KVM: Test SYSTEM_SUSPEND PSCI call selftests: KVM: Refactor psci_test to make it amenable to new tests selftests: KVM: Use KVM_SET_MP_STATE to power off vCPU in psci_test selftests: KVM: Create helper for making SMCCC calls selftests: KVM: Rename psci_cpu_on_test to psci_test KVM: arm64: Implement PSCI SYSTEM_SUSPEND KVM: arm64: Add support for userspace to suspend a vCPU KVM: arm64: Return a value from check_vcpu_requests() KVM: arm64: Rename the KVM_REQ_SLEEP handler KVM: arm64: Track vCPU power state using MP state values KVM: arm64: Dedupe vCPU power off helpers KVM: arm64: Don't depend on fallthrough to hide SYSTEM_RESET2 Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16Merge branch kvm-arm64/hcall-selection into kvmarm-master/nextMarc Zyngier
* kvm-arm64/hcall-selection: : . : Introduce a new set of virtual sysregs for userspace to : select the hypercalls it wants to see exposed to the guest. : : Patches courtesy of Raghavendra and Oliver. : . KVM: arm64: Fix hypercall bitmap writeback when vcpus have already run KVM: arm64: Hide KVM_REG_ARM_*_BMAP_BIT_COUNT from userspace Documentation: Fix index.rst after psci.rst renaming selftests: KVM: aarch64: Add the bitmap firmware registers to get-reg-list selftests: KVM: aarch64: Introduce hypercall ABI test selftests: KVM: Create helper for making SMCCC calls selftests: KVM: Rename psci_cpu_on_test to psci_test tools: Import ARM SMCCC definitions Docs: KVM: Add doc for the bitmap firmware registers Docs: KVM: Rename psci.rst to hypercalls.rst KVM: arm64: Add vendor hypervisor firmware register KVM: arm64: Add standard hypervisor firmware register KVM: arm64: Setup a framework for hypercall bitmap firmware registers KVM: arm64: Factor out firmware register handling from psci.c Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16KVM: arm64: Fix hypercall bitmap writeback when vcpus have already runMarc Zyngier
We generally want to disallow hypercall bitmaps being changed once vcpus have already run. But we must allow the write if the written value is unchanged so that userspace can rewrite the register file on reboot, for example. Without this, a QEMU-based VM will fail to reboot correctly. The original code was correct, and it is me that introduced the regression. Fixes: 05714cab7d63 ("KVM: arm64: Setup a framework for hypercall bitmap firmware registers") Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16KVM: arm64: vgic: Undo work in failed ITS restoresRicardo Koller
Failed ITS restores should clean up all state restored until the failure. There is some cleanup already present when failing to restore some tables, but it's not complete. Add the missing cleanup. Note that this changes the behavior in case of a failed restore of the device tables. restore ioctl: 1. restore collection tables 2. restore device tables With this commit, failures in 2. clean up everything created so far, including state created by 1. Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Ricardo Koller <ricarkol@google.com> Reviewed-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220510001633.552496-5-ricarkol@google.com
2022-05-16KVM: arm64: vgic: Do not ignore vgic_its_restore_cte failuresRicardo Koller
Restoring a corrupted collection entry (like an out of range ID) is being ignored and treated as success. More specifically, a vgic_its_restore_cte failure is treated as success by vgic_its_restore_collection_table. vgic_its_restore_cte uses positive and negative numbers to return error, and +1 to return success. The caller then uses "ret > 0" to check for success. Fix this by having vgic_its_restore_cte only return negative numbers on error. Do this by changing alloc_collection return codes to only return negative numbers on error. Signed-off-by: Ricardo Koller <ricarkol@google.com> Reviewed-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220510001633.552496-4-ricarkol@google.com
2022-05-16KVM: arm64: vgic: Add more checks when restoring ITS tablesRicardo Koller
Try to improve the predictability of ITS save/restores (and debuggability of failed ITS saves) by failing early on restore when trying to read corrupted tables. Restoring the ITS tables does some checks for corrupted tables, but not as many as in a save: an overflowing device ID will be detected on save but not on restore. The consequence is that restoring a corrupted table won't be detected until the next save; including the ITS not working as expected after the restore. As an example, if the guest sets tables overlapping each other, which would most likely result in some corrupted table, this is what we would see from the host point of view: guest sets base addresses that overlap each other save ioctl restore ioctl save ioctl (fails) Ideally, we would like the first save to fail, but overlapping tables could actually be intended by the guest. So, let's at least fail on the restore with some checks: like checking that device and event IDs don't overflow their tables. Signed-off-by: Ricardo Koller <ricarkol@google.com> Reviewed-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220510001633.552496-3-ricarkol@google.com
2022-05-16KVM: arm64: vgic: Check that new ITEs could be saved in guest memoryRicardo Koller
Try to improve the predictability of ITS save/restores by failing commands that would lead to failed saves. More specifically, fail any command that adds an entry into an ITS table that is not in guest memory, which would otherwise lead to a failed ITS save ioctl. There are already checks for collection and device entries, but not for ITEs. Add the corresponding check for the ITT when adding ITEs. Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Ricardo Koller <ricarkol@google.com> Reviewed-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220510001633.552496-2-ricarkol@google.com
2022-05-16KVM: arm64: pmu: Restore compilation when HW_PERF_EVENTS isn't selectedMarc Zyngier
Moving kvm_pmu_events into the vcpu (and refering to it) broke the somewhat unusual case where the kernel has no support for a PMU at all. In order to solve this, move things around a bit so that we can easily avoid refering to the pmu structure outside of PMU-aware code. As a bonus, pmu.c isn't compiled in when HW_PERF_EVENTS isn't selected. Reported-by: kernel test robot <lkp@intel.com> Reviewed-by: Fuad Tabba <tabba@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/202205161814.KQHpOzsJ-lkp@intel.com
2022-05-15KVM: arm64: Hide KVM_REG_ARM_*_BMAP_BIT_COUNT from userspaceMarc Zyngier
These constants will change over time, and userspace has no business knowing about them. Hide them behind __KERNEL__. Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-15KVM: arm64: Reenable pmu in Protected ModeFuad Tabba
Now that the pmu code does not access hyp data, reenable it in protected mode. Once fully supported, protected VMs will not have pmu support, since that could leak information. However, non-protected VMs in protected mode should have pmu support if available. Signed-off-by: Fuad Tabba <tabba@google.com> Reviewed-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220510095710.148178-5-tabba@google.com
2022-05-15KVM: arm64: Pass pmu events to hyp via vcpuFuad Tabba
Instead of the host accessing hyp data directly, pass the pmu events of the current cpu to hyp via the vcpu. This adds 64 bits (in two fields) to the vcpu that need to be synced before every vcpu run in nvhe and protected modes. However, it isolates the hypervisor from the host, which allows us to use pmu in protected mode in a subsequent patch. No visible side effects in behavior intended. Signed-off-by: Fuad Tabba <tabba@google.com> Reviewed-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220510095710.148178-4-tabba@google.com
2022-05-15KVM: arm64: Repack struct kvm_pmu to reduce sizeFuad Tabba
struct kvm_pmu has 2 holes using 10 bytes. This is instantiated in all vcpus, so it adds up. Repack the structures to remove the holes. No functional change intended. Reviewed-by: Oliver Upton <oupton@google.com> Signed-off-by: Fuad Tabba <tabba@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220510095710.148178-3-tabba@google.com
2022-05-15KVM: arm64: Wrapper for getting pmu_eventsFuad Tabba
Eases migrating away from using hyp data and simplifies the code. No functional change intended. Reviewed-by: Oliver Upton <oupton@google.com> Signed-off-by: Fuad Tabba <tabba@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220510095710.148178-2-tabba@google.com
2022-05-15KVM: arm64: vgic-v3: List M1 Pro/Max as requiring the SEIS workaroundMarc Zyngier
Unsusprisingly, Apple M1 Pro/Max have the exact same defect as the original M1 and generate random SErrors in the host when a guest tickles the GICv3 CPU interface the wrong way. Add the part numbers for both the CPU types found in these two new implementations, and add them to the hall of shame. This also applies to the Ultra version, as it is composed of 2 Max SoCs. Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20220514102524.3188730-1-maz@kernel.org
2022-05-12KVM: x86/mmu: Speed up slot_rmap_walk_next for sparsely populated rmapsVipin Sharma
Avoid calling handlers on empty rmap entries and skip to the next non empty rmap entry. Empty rmap entries are noop in handlers. Signed-off-by: Vipin Sharma <vipinsh@google.com> Suggested-by: Sean Christopherson <seanjc@google.com> Message-Id: <20220502220347.174664-1-vipinsh@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-12KVM: VMX: Include MKTME KeyID bits in shadow_zero_checkKai Huang
Intel MKTME KeyID bits (including Intel TDX private KeyID bits) should never be set to SPTE. Set shadow_me_value to 0 and shadow_me_mask to include all MKTME KeyID bits to include them to shadow_zero_check. Signed-off-by: Kai Huang <kai.huang@intel.com> Message-Id: <27bc10e97a3c0b58a4105ff9107448c190328239.1650363789.git.kai.huang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-12KVM: x86/mmu: Add shadow_me_value and repurpose shadow_me_maskKai Huang
Intel Multi-Key Total Memory Encryption (MKTME) repurposes couple of high bits of physical address bits as 'KeyID' bits. Intel Trust Domain Extentions (TDX) further steals part of MKTME KeyID bits as TDX private KeyID bits. TDX private KeyID bits cannot be set in any mapping in the host kernel since they can only be accessed by software running inside a new CPU isolated mode. And unlike to AMD's SME, host kernel doesn't set any legacy MKTME KeyID bits to any mapping either. Therefore, it's not legitimate for KVM to set any KeyID bits in SPTE which maps guest memory. KVM maintains shadow_zero_check bits to represent which bits must be zero for SPTE which maps guest memory. MKTME KeyID bits should be set to shadow_zero_check. Currently, shadow_me_mask is used by AMD to set the sme_me_mask to SPTE, and shadow_me_shadow is excluded from shadow_zero_check. So initializing shadow_me_mask to represent all MKTME keyID bits doesn't work for VMX (as oppositely, they must be set to shadow_zero_check). Introduce a new 'shadow_me_value' to replace existing shadow_me_mask, and repurpose shadow_me_mask as 'all possible memory encryption bits'. The new schematic of them will be: - shadow_me_value: the memory encryption bit(s) that will be set to the SPTE (the original shadow_me_mask). - shadow_me_mask: all possible memory encryption bits (which is a super set of shadow_me_value). - For now, shadow_me_value is supposed to be set by SVM and VMX respectively, and it is a constant during KVM's life time. This perhaps doesn't fit MKTME but for now host kernel doesn't support it (and perhaps will never do). - Bits in shadow_me_mask are set to shadow_zero_check, except the bits in shadow_me_value. Introduce a new helper kvm_mmu_set_me_spte_mask() to initialize them. Replace shadow_me_mask with shadow_me_value in almost all code paths, except the one in PT64_PERM_MASK, which is used by need_remote_flush() to determine whether remote TLB flush is needed. This should still use shadow_me_mask as any encryption bit change should need a TLB flush. And for AMD, move initializing shadow_me_value/shadow_me_mask from kvm_mmu_reset_all_pte_masks() to svm_hardware_setup(). Signed-off-by: Kai Huang <kai.huang@intel.com> Message-Id: <f90964b93a3398b1cf1c56f510f3281e0709e2ab.1650363789.git.kai.huang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-12KVM: x86/mmu: Rename reset_rsvds_bits_mask()Kai Huang
Rename reset_rsvds_bits_mask() to reset_guest_rsvds_bits_mask() to make it clearer that it resets the reserved bits check for guest's page table entries. Signed-off-by: Kai Huang <kai.huang@intel.com> Message-Id: <efdc174b85d55598880064b8bf09245d3791031d.1650363789.git.kai.huang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-12KVM: x86: a vCPU with a pending triple fault is runnablePaolo Bonzini
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-12KVM: x86/mmu: Expand and clean up page fault statsSean Christopherson
Expand and clean up the page fault stats. The current stats are at best incomplete, and at worst misleading. Differentiate between faults that are actually fixed vs those that result in an MMIO SPTE being created, track faults that are spurious, faults that trigger emulation, faults that that are fixed in the fast path, and last but not least, track the number of faults that are taken. Note, the number of faults that require emulation for write-protected shadow pages can roughly be calculated by subtracting the number of MMIO SPTEs created from the overall number of faults that trigger emulation. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20220423034752.1161007-10-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-12KVM: x86/mmu: Use IS_ENABLED() to avoid RETPOLINE for TDP page faultsSean Christopherson
Use IS_ENABLED() instead of an #ifdef to activate the anti-RETPOLINE fast path for TDP page faults. The generated code is identical, and the #ifdef makes it dangerously difficult to extend the logic (guess who forgot to add an "else" inside the #ifdef and ran through the page fault handler twice). No functional or binary change intented. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20220423034752.1161007-9-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-12KVM: x86/mmu: Make all page fault handlers internal to the MMUSean Christopherson
Move kvm_arch_async_page_ready() to mmu.c where it belongs, and move all of the page fault handling collateral that was in mmu.h purely for the async #PF handler into mmu_internal.h, where it belongs. This will allow kvm_mmu_do_page_fault() to act on the RET_PF_* return without having to expose those enums outside of the MMU. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20220423034752.1161007-8-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-12KVM: x86/mmu: Add RET_PF_CONTINUE to eliminate bool+int* "returns"Sean Christopherson
Add RET_PF_CONTINUE and use it in handle_abnormal_pfn() and kvm_faultin_pfn() to signal that the page fault handler should continue doing its thing. Aside from being gross and inefficient, using a boolean return to signal continue vs. stop makes it extremely difficult to add more helpers and/or move existing code to a helper. E.g. hypothetically, if nested MMUs were to gain a separate page fault handler in the future, everything up to the "is self-modifying PTE" check can be shared by all shadow MMUs, but communicating up the stack whether to continue on or stop becomes a nightmare. More concretely, proposed support for private guest memory ran into a similar issue, where it'll be forced to forego a helper in order to yield sane code: https://lore.kernel.org/all/YkJbxiL%2FAz7olWlq@google.com. No functional change intended. Cc: David Matlack <dmatlack@google.com> Cc: Chao Peng <chao.p.peng@linux.intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20220423034752.1161007-7-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-12KVM: x86/mmu: Drop exec/NX check from "page fault can be fast"Sean Christopherson
Tweak the "page fault can be fast" logic to explicitly check for !PRESENT faults in the access tracking case, and drop the exec/NX check that becomes redundant as a result. No sane hardware will generate an access that is both an instruct fetch and a write, i.e. it's a waste of cycles. If hardware goes off the rails, or KVM runs under a misguided hypervisor, spuriously running throught fast path is benign (KVM has been uknowingly being doing exactly that for years). Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20220423034752.1161007-6-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-12KVM: x86/mmu: Don't attempt fast page fault just because EPT is in useSean Christopherson
Check for A/D bits being disabled instead of the access tracking mask being non-zero when deciding whether or not to attempt to fix a page fault vian the fast path. Originally, the access tracking mask was non-zero if and only if A/D bits were disabled by _KVM_ (including not being supported by hardware), but that hasn't been true since nVMX was fixed to honor EPTP12's A/D enabling, i.e. since KVM allowed L1 to cause KVM to not use A/D bits while running L2 despite KVM using them while running L1. In other words, don't attempt the fast path just because EPT is enabled. Note, attempting the fast path for all !PRESENT faults can "fix" a very, _VERY_ tiny percentage of faults out of mmu_lock by detecting that the fault is spurious, i.e. has been fixed by a different vCPU, but again the odds of that happening are vanishingly small. E.g. booting an 8-vCPU VM gets less than 10 successes out of 30k+ faults, and that's likely one of the more favorable scenarios. Disabling dirty logging can likely lead to a rash of collisions between vCPUs for some workloads that operate on a common set of pages, but penalizing _all_ !PRESENT faults for that one case is unlikely to be a net positive, not to mention that that problem is best solved by not zapping in the first place. The number of spurious faults does scale with the number of vCPUs, e.g. a 255-vCPU VM using TDP "jumps" to ~60 spurious faults detected in the fast path (again out of 30k), but that's all of 0.2% of faults. Using legacy shadow paging does get more spurious faults, and a few more detected out of mmu_lock, but the percentage goes _down_ to 0.08% (and that's ignoring faults that are reflected into the guest), i.e. the extra detections are purely due to the sheer number of faults observed. On the other hand, getting a "negative" in the fast path takes in the neighborhood of 150-250 cycles. So while it is tempting to keep/extend the current behavior, such a change needs to come with hard numbers showing that it's actually a win in the grand scheme, or any scheme for that matter. Fixes: 995f00a61958 ("x86: kvm: mmu: use ept a/d in vmcs02 iff used in vmcs12") Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20220423034752.1161007-5-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-12KVM: VMX: clean up pi_wakeup_handlerLi RongQing
Passing per_cpu() to list_for_each_entry() causes the macro to be evaluated N+1 times for N sleeping vCPUs. This is a very small inefficiency, and the code is cleaner if the address of the per-CPU variable is loaded earlier. Do this for both the list and the spinlock. Signed-off-by: Li RongQing <lirongqing@baidu.com> Message-Id: <1649244302-6777-1-git-send-email-lirongqing@baidu.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-12KVM: x86: fix typo in __try_cmpxchg_user causing non-atomicnessMaxim Levitsky
This shows up as a TDP MMU leak when running nested. Non-working cmpxchg on L0 relies makes L1 install two different shadow pages under same spte, and one of them is leaked. Fixes: 1c2361f667f36 ("KVM: x86: Use __try_cmpxchg_user() to emulate atomic accesses") Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> Message-Id: <20220512101420.306759-1-mlevitsk@redhat.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-10KVM: arm64: pkvm: Don't mask already zeroed FEAT_SVEOliver Upton
FEAT_SVE is already masked by the fixed configuration for ID_AA64PFR0_EL1; don't try and mask it at runtime. No functional change intended. Signed-off-by: Oliver Upton <oupton@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220509162559.2387784-3-oupton@google.com
2022-05-10KVM: arm64: pkvm: Drop unnecessary FP/SIMD trap handlerOliver Upton
The pVM-specific FP/SIMD trap handler just calls straight into the generic trap handler. Avoid the indirection and just call the hyp handler directly. Note that the BUILD_BUG_ON() pattern is repeated in pvm_init_traps_aa64pfr0(), which is likely a better home for it. No functional change intended. Signed-off-by: Oliver Upton <oupton@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220509162559.2387784-2-oupton@google.com
2022-05-06KVM: arm64: nvhe: Eliminate kernel-doc warningsRandy Dunlap
Don't use begin-kernel-doc notation (/**) for comments that are not in kernel-doc format. This prevents these kernel-doc warnings: arch/arm64/kvm/hyp/nvhe/switch.c:126: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * Disable host events, enable guest events arch/arm64/kvm/hyp/nvhe/switch.c:146: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * Disable guest events, enable host events arch/arm64/kvm/hyp/nvhe/switch.c:164: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * Handler for protected VM restricted exceptions. arch/arm64/kvm/hyp/nvhe/switch.c:176: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * Handler for protected VM MSR, MRS or System instruction execution in AArch64. arch/arm64/kvm/hyp/nvhe/switch.c:196: warning: Function parameter or member 'vcpu' not described in 'kvm_handle_pvm_fpsimd' arch/arm64/kvm/hyp/nvhe/switch.c:196: warning: Function parameter or member 'exit_code' not described in 'kvm_handle_pvm_fpsimd' arch/arm64/kvm/hyp/nvhe/switch.c:196: warning: expecting prototype for Handler for protected floating(). Prototype was for kvm_handle_pvm_fpsimd() instead Fixes: 09cf57eba304 ("KVM: arm64: Split hyp/switch.c to VHE/nVHE") Fixes: 1423afcb4117 ("KVM: arm64: Trap access to pVM restricted features") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: kernel test robot <lkp@intel.com> Cc: Fuad Tabba <tabba@google.com> Cc: Marc Zyngier <maz@kernel.org> Cc: David Brazdil <dbrazdil@google.com> Cc: James Morse <james.morse@arm.com> Cc: Alexandru Elisei <alexandru.elisei@arm.com> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: kvmarm@lists.cs.columbia.edu Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220430050123.2844-1-rdunlap@infradead.org
2022-05-06KVM: arm64: Avoid unnecessary absolute addressing via literalsArd Biesheuvel
There are a few cases in the nVHE code where we take the absolute address of a symbol via a literal pool entry, and subsequently translate it to another address space (PA, kimg VA, kernel linear VA, etc). Originally, this literal was needed because we relied on a different translation for absolute references, but this is no longer the case, so we can simply use relative addressing instead. This removes a couple of RELA entries pointing into the .text segment. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220428140350.3303481-1-ardb@kernel.org
2022-05-05Documentation: KVM: Fix title level for PSCI_SUSPENDStephen Rothwell
The htmldoc build breaks in a funny way with: <quote> Sphinx parallel build error: docutils.utils.SystemMessage: /home/sfr/next/next/Documentation/virt/kvm/api.rst:6175: (SEVERE/4) Title level inconsistent: For arm/arm64: ^^^^^^^^^^^^^^ </quote> Swap the ^^s for a bunch of --s... Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> [maz: commit message] Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-04KVM: arm64: Print emulated register table name when it is unsortedAlexandru Elisei
When a sysreg table entry is out-of-order, KVM attempts to print the address of the table: [ 0.143911] kvm [1]: sys_reg table (____ptrval____) out of order (1) Printing the name of the table instead of a pointer is more helpful in this case. The message has also been slightly tweaked to be point out the offending entry (and to match the missing reset error message): [ 0.143891] kvm [1]: sys_reg table sys_reg_descs+0x50/0x7490 entry 1 out of order Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220428103405.70884-3-alexandru.elisei@arm.com
2022-05-04KVM: arm64: Don't BUG_ON() if emulated register table is unsortedAlexandru Elisei
To emulate a register access, KVM uses a table of registers sorted by register encoding to speed up queries using binary search. When Linux boots, KVM checks that the table is sorted and uses a BUG_ON() statement to let the user know if it's not. The unfortunate side effect is that an unsorted sysreg table brings down the whole kernel, not just KVM, even though the rest of the kernel can function just fine without KVM. To make matters worse, on machines which lack a serial console, the user is left pondering why the machine is taking so long to boot. Improve this situation by returning an error from kvm_arch_init() if the sysreg tables are not in the correct order. The machine is still very much usable for the user, with the exception of virtualization, who can now easily determine what went wrong. A minor typo has also been corrected in the check_sysreg_table() function. Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220428103405.70884-2-alexandru.elisei@arm.com
2022-05-04KVM: arm64: vgic-v3: Advertise GICR_CTLR.{IR, CES} as a new GICD_IIDR revisionMarc Zyngier
Since adversising GICR_CTLR.{IC,CES} is directly observable from a guest, we need to make it selectable from userspace. For that, bump the default GICD_IIDR revision and let userspace downgrade it to the previous default. For GICv2, the two distributor revisions are strictly equivalent. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220405182327.205520-5-maz@kernel.org
2022-05-04KVM: arm64: vgic-v3: Implement MMIO-based LPI invalidationMarc Zyngier
Since GICv4.1, it has become legal for an implementation to advertise GICR_{INVLPIR,INVALLR,SYNCR} while having an ITS, allowing for a more efficient invalidation scheme (no guest command queue contention when multiple CPUs are generating invalidations). Provide the invalidation registers as a primitive to their ITS counterpart. Note that we don't advertise them to the guest yet (the architecture allows an implementation to do this). Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Oliver Upton <oupton@google.com> Link: https://lore.kernel.org/r/20220405182327.205520-4-maz@kernel.org
2022-05-04KVM: arm64: vgic-v3: Expose GICR_CTLR.RWP when disabling LPIsMarc Zyngier
When disabling LPIs, a guest needs to poll GICR_CTLR.RWP in order to be sure that the write has taken effect. We so far reported it as 0, as we didn't advertise that LPIs could be turned off the first place. Start tracking this state during which LPIs are being disabled, and expose the 'in progress' state via the RWP bit. We also take this opportunity to disallow enabling LPIs and programming GICR_{PEND,PROP}BASER while LPI disabling is in progress, as allowed by the architecture (UNPRED behaviour). We don't advertise the feature to the guest yet (which is allowed by the architecture). Reviewed-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220405182327.205520-3-maz@kernel.org
2022-05-04irqchip/gic-v3: Exposes bit values for GICR_CTLR.{IR, CES}Marc Zyngier
As we're about to expose GICR_CTLR.{IR,CES} to guests, populate the include file with the architectural values. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Oliver Upton <oupton@google.com> Link: https://lore.kernel.org/r/20220405182327.205520-2-maz@kernel.org
2022-05-04Documentation: Fix index.rst after psci.rst renamingMarc Zyngier
Fix the TOC in index.rst after psci.rst has been renamed to hypercalls.rst. Signed-off-by: Marc Zyngier <maz@kernel.org> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Link: https://lore.kernel.org/r/20220504205627.18f46380@canb.auug.org.au
2022-05-04Merge branch kvm-arm64/aarch32-idreg-trap into kvmarm-master/nextMarc Zyngier
* kvm-arm64/aarch32-idreg-trap: : . : Add trapping/sanitising infrastructure for AArch32 systen registers, : allowing more control over what we actually expose (such as the PMU). : : Patches courtesy of Oliver and Alexandru. : . KVM: arm64: Fix new instances of 32bit ESRs KVM: arm64: Hide AArch32 PMU registers when not available KVM: arm64: Start trapping ID registers for 32 bit guests KVM: arm64: Plumb cp10 ID traps through the AArch64 sysreg handler KVM: arm64: Wire up CP15 feature registers to their AArch64 equivalents KVM: arm64: Don't write to Rt unless sys_reg emulation succeeds KVM: arm64: Return a bool from emulate_cp() Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-04Merge branch kvm-arm64/hyp-stack-guard into kvmarm-master/nextMarc Zyngier
* kvm-arm64/hyp-stack-guard: : . : Harden the EL2 stack by providing stack guards, courtesy of : Kalesh Singh. : . KVM: arm64: Symbolize the nVHE HYP addresses KVM: arm64: Detect and handle hypervisor stack overflows KVM: arm64: Add guard pages for pKVM (protected nVHE) hypervisor stack KVM: arm64: Add guard pages for KVM nVHE hypervisor stack KVM: arm64: Introduce pkvm_alloc_private_va_range() KVM: arm64: Introduce hyp_alloc_private_va_range() Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-04Merge branch kvm-arm64/wfxt into kvmarm-master/nextMarc Zyngier
* kvm-arm64/wfxt: : . : Add support for the WFET/WFIT instructions that provide the same : service as WFE/WFI, only with a timeout. : . KVM: arm64: Expose the WFXT feature to guests KVM: arm64: Offer early resume for non-blocking WFxT instructions KVM: arm64: Handle blocking WFIT instruction KVM: arm64: Introduce kvm_counter_compute_delta() helper KVM: arm64: Simplify kvm_cpu_has_pending_timer() arm64: Use WFxT for __delay() when possible arm64: Add wfet()/wfit() helpers arm64: Add HWCAP advertising FEAT_WFXT arm64: Add RV and RN fields for ESR_ELx_WFx_ISS arm64: Expand ESR_ELx_WFx_ISS_TI to match its ARMv8.7 definition Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-04Merge remote-tracking branch 'arm64/for-next/sme' into kvmarm-master/nextMarc Zyngier
Merge arm64's SME branch to resolve conflicts with the WFxT branch. Signed-off-by: Marc Zyngier <maz@kernel.org>