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* Merge tag 'kvmarm-fixes-6.13-2' of ↵Paolo Bonzini2024-12-104-6/+24
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 6.13, part #2 - Fix confusion with implicitly-shifted MDCR_EL2 masks breaking SPE/TRBE initialization - Align nested page table walker with the intended memory attribute combining rules of the architecture - Prevent userspace from constraining the advertised ASID width, avoiding horrors of guest TLBIs not matching the intended context in hardware - Don't leak references on LPIs when insertion into the translation cache fails
| * KVM: arm64: vgic-its: Add error handling in vgic_its_cache_translationKeisuke Nishimura2024-12-041-1/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The return value of xa_store() needs to be checked. This fix adds an error handling path that resolves the kref inconsistency on failure. As suggested by Oliver Upton, this function does not return the error code intentionally because the translation cache is best effort. Fixes: 8201d1028caa ("KVM: arm64: vgic-its: Maintain a translation cache per ITS") Signed-off-by: Keisuke Nishimura <keisuke.nishimura@inria.fr> Suggested-by: Oliver Upton <oliver.upton@linux.dev> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241130144952.23729-1-keisuke.nishimura@inria.fr Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| * KVM: arm64: Do not allow ID_AA64MMFR0_EL1.ASIDbits to be overriddenMarc Zyngier2024-12-041-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Catalin reports that a hypervisor lying to a guest about the size of the ASID field may result in unexpected issues: - if the underlying HW does only supports 8 bit ASIDs, the ASID field in a TLBI VAE1* operation is only 8 bits, and the HW will ignore the other 8 bits - if on the contrary the HW is 16 bit capable, the ASID field in the same TLBI operation is always 16 bits, irrespective of the value of TCR_ELx.AS. This could lead to missed invalidations if the guest was lead to assume that the HW had 8 bit ASIDs while they really are 16 bit wide. In order to avoid any potential disaster that would be hard to debug, prenent the migration between a host with 8 bit ASIDs to one with wider ASIDs (the converse was obviously always forbidden). This is also consistent with what we already do for VMIDs. If it becomes absolutely mandatory to support such a migration path in the future, we will have to trap and emulate all TLBIs, something that nobody should look forward to. Fixes: d5a32b60dc18 ("KVM: arm64: Allow userspace to change ID_AA64MMFR{0-2}_EL1") Reported-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Oliver Upton <oliver.upton@linux.dev> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20241203190236.505759-1-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| * KVM: arm64: Fix S1/S2 combination when FWB==1 and S2 has Device memory typeMarc Zyngier2024-11-261-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The G.a revision of the ARM ARM had it pretty clear that HCR_EL2.FWB had no influence on "The way that stage 1 memory types and attributes are combined with stage 2 Device type and attributes." (D5.5.5). However, this wording was lost in further revisions of the architecture. Restore the intended behaviour, which is to take the strongest memory type of S1 and S2 in this case, as if FWB was 0. The specification is being fixed accordingly. Fixes: be04cebf3e788 ("KVM: arm64: nv: Add emulation of AT S12E{0,1}{R,W}") Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241125094756.609590-1-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| * arm64: Fix usage of new shifted MDCR_EL2 valuesJames Clark2024-11-261-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Since the linked fixes commit, these masks are already shifted so remove the shifts. One issue that this fixes is SPE and TRBE not being available anymore: arm_spe_pmu arm,spe-v1: profiling buffer owned by higher exception level Fixes: 641630313e9c ("arm64: sysreg: Migrate MDCR_EL2 definition to table") Signed-off-by: James Clark <james.clark@linaro.org> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241122164636.2944180-1-james.clark@linaro.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
* | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2024-11-3013-117/+172
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull more kvm updates from Paolo Bonzini: - ARM fixes - RISC-V Svade and Svadu (accessed and dirty bit) extension support for host and guest * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: riscv: selftests: Add Svade and Svadu Extension to get-reg-list test RISC-V: KVM: Add Svade and Svadu Extensions Support for Guest/VM dt-bindings: riscv: Add Svade and Svadu Entries RISC-V: Add Svade and Svadu Extensions Support KVM: arm64: Use MDCR_EL2.HPME to evaluate overflow of hyp counters KVM: arm64: Ignore PMCNTENSET_EL0 while checking for overflow status KVM: arm64: Mark set_sysreg_masks() as inline to avoid build failure KVM: arm64: vgic-its: Add stronger type-checking to the ITS entry sizes KVM: arm64: vgic: Kill VGIC_MAX_PRIVATE definition KVM: arm64: vgic: Make vgic_get_irq() more robust KVM: arm64: vgic-v3: Sanitise guest writes to GICR_INVLPIR
| * | Merge tag 'kvmarm-fixes-6.13-1' of ↵Paolo Bonzini2024-11-2113-117/+172
| |\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 changes for 6.13, part #2 - Constrain invalidations from GICR_INVLPIR to only affect the LPI INTID space - Set of robustness improvements to the management of vgic irqs and GIC ITS table entries - Fix compilation issue w/ CONFIG_CC_OPTIMIZE_FOR_SIZE=y where set_sysreg_masks() wasn't getting inlined, breaking check for a constant sysreg index - Correct KVM's vPMU overflow condition to match the architecture for hyp and non-hyp counters
| | * KVM: arm64: Use MDCR_EL2.HPME to evaluate overflow of hyp countersOliver Upton2024-11-211-16/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The 'global enable control' (as it is termed in the architecture) for counters reserved by EL2 is MDCR_EL2.HPME. Use that instead of PMCR_EL0.E when evaluating the overflow state for hyp counters. Change the return value to a bool while at it, which better reflects the fact that the overflow state is a shared signal and not a per-counter property. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241120005230.2335682-3-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | * KVM: arm64: Ignore PMCNTENSET_EL0 while checking for overflow statusRaghavendra Rao Ananta2024-11-211-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DDI0487K.a D13.3.1 describes the PMU overflow condition, which evaluates to true if any counter's global enable (PMCR_EL0.E), overflow flag (PMOVSSET_EL0[n]), and interrupt enable (PMINTENSET_EL1[n]) are all 1. Of note, this does not require a counter to be enabled (i.e. PMCNTENSET_EL0[n] = 1) to generate an overflow. Align kvm_pmu_overflow_status() with the reality of the architecture and stop using PMCNTENSET_EL0 as part of the overflow condition. The bug was discovered while running an SBSA PMU test [*], which only sets PMCR.E, PMOVSSET<0>, PMINTENSET<0>, and expects an overflow interrupt. Cc: stable@vger.kernel.org Fixes: 76d883c4e640 ("arm64: KVM: Add access handler for PMOVSSET and PMOVSCLR register") Link: https://github.com/ARM-software/sbsa-acs/blob/master/test_pool/pmu/operating_system/test_pmu001.c Signed-off-by: Raghavendra Rao Ananta <rananta@google.com> [ oliver: massaged changelog ] Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241120005230.2335682-2-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | * KVM: arm64: Mark set_sysreg_masks() as inline to avoid build failureMarc Zyngier2024-11-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When compiling with CONFIG_CC_OPTIMIZE_FOR_SIZE=y, set_sysreg_masks() fails to compile thanks to: BUILD_BUG_ON(!__builtin_constant_p(sr)); as the compiler doesn't identify sr as a constant, despite all the callers passing constants. Fix the issue by always inlining this function, which allows GCC to do the right thing. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202411201857.ZNudtGJl-lkp@intel.com/ Fixes: a0162020095e2 ("KVM: arm64: Extend masking facility to arbitrary registers") Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Joey Gouly <joey.gouly@arm.com> Link: https://lore.kernel.org/r/20241120111516.304250-1-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | * KVM: arm64: vgic-its: Add stronger type-checking to the ITS entry sizesMarc Zyngier2024-11-212-42/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ITS ABI infrastructure allows for some pretty lax code, where the size of the data doesn't have to match the size of the entry, potentially leading to a collection of interesting bugs. Commit 7fe28d7e68f9 ("KVM: arm64: vgic-its: Add a data length check in vgic_its_save_*") added some checks, but starts by implicitly casting all writes to a 64bit value, hiding some of the issues. Instead, introduce macros that will check the data type actually used for dealing with the table entries. The macros are taking a symbolic entry type that is used to fetch the size of the entry type for the current ABI. This immediately catches a couple of low-impact gotchas (zero values that are implicitly 32bit), easy enough to fix. Given that we currently only have a single ABI, hardcode a couple of BUILD_BUG_ON()s that will fire if we use anything but a 64bit quantity, and some (currently unreachable) fallback code that may become useful one day. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241117165757.247686-5-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | * KVM: arm64: vgic: Kill VGIC_MAX_PRIVATE definitionMarc Zyngier2024-11-211-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | VGIC_MAX_PRIVATE is a pretty useless definition, and is better replaced with VGIC_NR_PRIVATE_IRQS. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241117165757.247686-4-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | * KVM: arm64: vgic: Make vgic_get_irq() more robustMarc Zyngier2024-11-2111-57/+71
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | vgic_get_irq() has an awkward signature, as it takes both a kvm *and* a vcpu, where the vcpu is allowed to be NULL if the INTID being looked up is a global interrupt (SPI or LPI). This leads to potentially problematic situations where the INTID passed is a private interrupt, but that there is no vcpu. In order to make things less ambiguous, let have *two* helpers instead: - vgic_get_irq(struct kvm *kvm, u32 intid), which is only concerned with *global* interrupts, as indicated by the lack of vcpu. - vgic_get_vcpu_irq(struct kvm_vcpu *vcpu, u32 intid), which can return *any* interrupt class, but must have of course a non-NULL vcpu. Most of the code nicely falls under one or the other situations, except for a couple of cases (close to the UABI or in the debug code) where we have to distinguish between the two cases. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241117165757.247686-3-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | * KVM: arm64: vgic-v3: Sanitise guest writes to GICR_INVLPIRMarc Zyngier2024-11-211-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make sure we filter out non-LPI invalidation when handling writes to GICR_INVLPIR. Fixes: 4645d11f4a553 ("KVM: arm64: vgic-v3: Implement MMIO-based LPI invalidation") Reported-by: Alexander Potapenko <glider@google.com> Tested-by: Alexander Potapenko <glider@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20241117165757.247686-2-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
* | | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2024-11-2426-391/+1482
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull kvm updates from Paolo Bonzini: "The biggest change here is eliminating the awful idea that KVM had of essentially guessing which pfns are refcounted pages. The reason to do so was that KVM needs to map both non-refcounted pages (for example BARs of VFIO devices) and VM_PFNMAP/VM_MIXMEDMAP VMAs that contain refcounted pages. However, the result was security issues in the past, and more recently the inability to map VM_IO and VM_PFNMAP memory that _is_ backed by struct page but is not refcounted. In particular this broke virtio-gpu blob resources (which directly map host graphics buffers into the guest as "vram" for the virtio-gpu device) with the amdgpu driver, because amdgpu allocates non-compound higher order pages and the tail pages could not be mapped into KVM. This requires adjusting all uses of struct page in the per-architecture code, to always work on the pfn whenever possible. The large series that did this, from David Stevens and Sean Christopherson, also cleaned up substantially the set of functions that provided arch code with the pfn for a host virtual addresses. The previous maze of twisty little passages, all different, is replaced by five functions (__gfn_to_page, __kvm_faultin_pfn, the non-__ versions of these two, and kvm_prefetch_pages) saving almost 200 lines of code. ARM: - Support for stage-1 permission indirection (FEAT_S1PIE) and permission overlays (FEAT_S1POE), including nested virt + the emulated page table walker - Introduce PSCI SYSTEM_OFF2 support to KVM + client driver. This call was introduced in PSCIv1.3 as a mechanism to request hibernation, similar to the S4 state in ACPI - Explicitly trap + hide FEAT_MPAM (QoS controls) from KVM guests. As part of it, introduce trivial initialization of the host's MPAM context so KVM can use the corresponding traps - PMU support under nested virtualization, honoring the guest hypervisor's trap configuration and event filtering when running a nested guest - Fixes to vgic ITS serialization where stale device/interrupt table entries are not zeroed when the mapping is invalidated by the VM - Avoid emulated MMIO completion if userspace has requested synchronous external abort injection - Various fixes and cleanups affecting pKVM, vCPU initialization, and selftests LoongArch: - Add iocsr and mmio bus simulation in kernel. - Add in-kernel interrupt controller emulation. - Add support for virtualization extensions to the eiointc irqchip. PPC: - Drop lingering and utterly obsolete references to PPC970 KVM, which was removed 10 years ago. - Fix incorrect documentation references to non-existing ioctls RISC-V: - Accelerate KVM RISC-V when running as a guest - Perf support to collect KVM guest statistics from host side s390: - New selftests: more ucontrol selftests and CPU model sanity checks - Support for the gen17 CPU model - List registers supported by KVM_GET/SET_ONE_REG in the documentation x86: - Cleanup KVM's handling of Accessed and Dirty bits to dedup code, improve documentation, harden against unexpected changes. Even if the hardware A/D tracking is disabled, it is possible to use the hardware-defined A/D bits to track if a PFN is Accessed and/or Dirty, and that removes a lot of special cases. - Elide TLB flushes when aging secondary PTEs, as has been done in x86's primary MMU for over 10 years. - Recover huge pages in-place in the TDP MMU when dirty page logging is toggled off, instead of zapping them and waiting until the page is re-accessed to create a huge mapping. This reduces vCPU jitter. - Batch TLB flushes when dirty page logging is toggled off. This reduces the time it takes to disable dirty logging by ~3x. - Remove the shrinker that was (poorly) attempting to reclaim shadow page tables in low-memory situations. - Clean up and optimize KVM's handling of writes to MSR_IA32_APICBASE. - Advertise CPUIDs for new instructions in Clearwater Forest - Quirk KVM's misguided behavior of initialized certain feature MSRs to their maximum supported feature set, which can result in KVM creating invalid vCPU state. E.g. initializing PERF_CAPABILITIES to a non-zero value results in the vCPU having invalid state if userspace hides PDCM from the guest, which in turn can lead to save/restore failures. - Fix KVM's handling of non-canonical checks for vCPUs that support LA57 to better follow the "architecture", in quotes because the actual behavior is poorly documented. E.g. most MSR writes and descriptor table loads ignore CR4.LA57 and operate purely on whether the CPU supports LA57. - Bypass the register cache when querying CPL from kvm_sched_out(), as filling the cache from IRQ context is generally unsafe; harden the cache accessors to try to prevent similar issues from occuring in the future. The issue that triggered this change was already fixed in 6.12, but was still kinda latent. - Advertise AMD_IBPB_RET to userspace, and fix a related bug where KVM over-advertises SPEC_CTRL when trying to support cross-vendor VMs. - Minor cleanups - Switch hugepage recovery thread to use vhost_task. These kthreads can consume significant amounts of CPU time on behalf of a VM or in response to how the VM behaves (for example how it accesses its memory); therefore KVM tried to place the thread in the VM's cgroups and charge the CPU time consumed by that work to the VM's container. However the kthreads did not process SIGSTOP/SIGCONT, and therefore cgroups which had KVM instances inside could not complete freezing. Fix this by replacing the kthread with a PF_USER_WORKER thread, via the vhost_task abstraction. Another 100+ lines removed, with generally better behavior too like having these threads properly parented in the process tree. - Revert a workaround for an old CPU erratum (Nehalem/Westmere) that didn't really work; there was really nothing to work around anyway: the broken patch was meant to fix nested virtualization, but the PERF_GLOBAL_CTRL MSR is virtualized and therefore unaffected by the erratum. - Fix 6.12 regression where CONFIG_KVM will be built as a module even if asked to be builtin, as long as neither KVM_INTEL nor KVM_AMD is 'y'. x86 selftests: - x86 selftests can now use AVX. Documentation: - Use rST internal links - Reorganize the introduction to the API document Generic: - Protect vcpu->pid accesses outside of vcpu->mutex with a rwlock instead of RCU, so that running a vCPU on a different task doesn't encounter long due to having to wait for all CPUs become quiescent. In general both reads and writes are rare, but userspace that supports confidential computing is introducing the use of "helper" vCPUs that may jump from one host processor to another. Those will be very happy to trigger a synchronize_rcu(), and the effect on performance is quite the disaster" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (298 commits) KVM: x86: Break CONFIG_KVM_X86's direct dependency on KVM_INTEL || KVM_AMD KVM: x86: add back X86_LOCAL_APIC dependency Revert "KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata handling out of setup_vmcs_config()" KVM: x86: switch hugepage recovery thread to vhost_task KVM: x86: expose MSR_PLATFORM_INFO as a feature MSR x86: KVM: Advertise CPUIDs for new instructions in Clearwater Forest Documentation: KVM: fix malformed table irqchip/loongson-eiointc: Add virt extension support LoongArch: KVM: Add irqfd support LoongArch: KVM: Add PCHPIC user mode read and write functions LoongArch: KVM: Add PCHPIC read and write functions LoongArch: KVM: Add PCHPIC device support LoongArch: KVM: Add EIOINTC user mode read and write functions LoongArch: KVM: Add EIOINTC read and write functions LoongArch: KVM: Add EIOINTC device support LoongArch: KVM: Add IPI user mode read and write function LoongArch: KVM: Add IPI read and write function LoongArch: KVM: Add IPI device support LoongArch: KVM: Add iocsr and mmio bus simulation in kernel KVM: arm64: Pass on SVE mapping failures ...
| * | Merge tag 'kvmarm-6.13' of ↵Paolo Bonzini2024-11-1423-365/+1466
| |\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 changes for 6.13, part #1 - Support for stage-1 permission indirection (FEAT_S1PIE) and permission overlays (FEAT_S1POE), including nested virt + the emulated page table walker - Introduce PSCI SYSTEM_OFF2 support to KVM + client driver. This call was introduced in PSCIv1.3 as a mechanism to request hibernation, similar to the S4 state in ACPI - Explicitly trap + hide FEAT_MPAM (QoS controls) from KVM guests. As part of it, introduce trivial initialization of the host's MPAM context so KVM can use the corresponding traps - PMU support under nested virtualization, honoring the guest hypervisor's trap configuration and event filtering when running a nested guest - Fixes to vgic ITS serialization where stale device/interrupt table entries are not zeroed when the mapping is invalidated by the VM - Avoid emulated MMIO completion if userspace has requested synchronous external abort injection - Various fixes and cleanups affecting pKVM, vCPU initialization, and selftests
| | * KVM: arm64: Pass on SVE mapping failuresJames Clark2024-11-121-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This function can fail but its return value isn't passed onto the caller. Presumably this could result in a broken state. Fixes: 66d5b53e20a6 ("KVM: arm64: Allocate memory mapped at hyp for host sve state in pKVM") Signed-off-by: James Clark <james.clark@linaro.org> Reviewed-by: Fuad Tabba <tabba@google.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241112105604.795809-1-james.clark@linaro.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | * Merge branch kvm-arm64/vgic-its-fixes into kvmarm/nextOliver Upton2024-11-112-15/+40
| | |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * kvm-arm64/vgic-its-fixes: : Fixes for vgic-its save/restore, courtesy of Kunkun Jiang and Jing Zhang : : Address bugs where restoring an ITS consumes a stale DTE/ITE, which : may lead to either garbage mappings in the ITS or the overall restore : ioctl failing. The fix in both cases is to zero a DTE/ITE when its : translation has been invalidated by the guest. KVM: arm64: vgic-its: Clear ITE when DISCARD frees an ITE KVM: arm64: vgic-its: Clear DTE when MAPD unmaps a device KVM: arm64: vgic-its: Add a data length check in vgic_its_save_* Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * KVM: arm64: vgic-its: Clear ITE when DISCARD frees an ITEKunkun Jiang2024-11-111-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When DISCARD frees an ITE, it does not invalidate the corresponding ITE. In the scenario of continuous saves and restores, there may be a situation where an ITE is not saved but is restored. This is unreasonable and may cause restore to fail. This patch clears the corresponding ITE when DISCARD frees an ITE. Cc: stable@vger.kernel.org Fixes: eff484e0298d ("KVM: arm64: vgic-its: ITT save and restore") Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com> [Jing: Update with entry write helper] Signed-off-by: Jing Zhang <jingzhangos@google.com> Link: https://lore.kernel.org/r/20241107214137.428439-6-jingzhangos@google.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * KVM: arm64: vgic-its: Clear DTE when MAPD unmaps a deviceKunkun Jiang2024-11-111-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | vgic_its_save_device_tables will traverse its->device_list to save DTE for each device. vgic_its_restore_device_tables will traverse each entry of device table and check if it is valid. Restore if valid. But when MAPD unmaps a device, it does not invalidate the corresponding DTE. In the scenario of continuous saves and restores, there may be a situation where a device's DTE is not saved but is restored. This is unreasonable and may cause restore to fail. This patch clears the corresponding DTE when MAPD unmaps a device. Cc: stable@vger.kernel.org Fixes: 57a9a117154c ("KVM: arm64: vgic-its: Device table save/restore") Co-developed-by: Shusen Li <lishusen2@huawei.com> Signed-off-by: Shusen Li <lishusen2@huawei.com> Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com> [Jing: Update with entry write helper] Signed-off-by: Jing Zhang <jingzhangos@google.com> Link: https://lore.kernel.org/r/20241107214137.428439-5-jingzhangos@google.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * KVM: arm64: vgic-its: Add a data length check in vgic_its_save_*Jing Zhang2024-11-112-12/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In all the vgic_its_save_*() functinos, they do not check whether the data length is 8 bytes before calling vgic_write_guest_lock. This patch adds the check. To prevent the kernel from being blown up when the fault occurs, KVM_BUG_ON() is used. And the other BUG_ON()s are replaced together. Cc: stable@vger.kernel.org Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com> [Jing: Update with the new entry read/write helpers] Signed-off-by: Jing Zhang <jingzhangos@google.com> Link: https://lore.kernel.org/r/20241107214137.428439-4-jingzhangos@google.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | * | Merge branch kvm-arm64/nv-pmu into kvmarm/nextOliver Upton2024-11-114-141/+345
| | |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * kvm-arm64/nv-pmu: : Support for vEL2 PMU controls : : Align the vEL2 PMU support with the current state of non-nested KVM, : including: : : - Trap routing, with the annoying complication of EL2 traps that apply : in Host EL0 : : - PMU emulation, using the correct configuration bits depending on : whether a counter falls in the hypervisor or guest range of PMCs : : - Perf event swizzling across nested boundaries, as the event filtering : needs to be remapped to cope with vEL2 KVM: arm64: nv: Reprogram PMU events affected by nested transition KVM: arm64: nv: Apply EL2 event filtering when in hyp context KVM: arm64: nv: Honor MDCR_EL2.HLP KVM: arm64: nv: Honor MDCR_EL2.HPME KVM: arm64: Add helpers to determine if PMC counts at a given EL KVM: arm64: nv: Adjust range of accessible PMCs according to HPMN KVM: arm64: Rename kvm_pmu_valid_counter_mask() KVM: arm64: nv: Advertise support for FEAT_HPMN0 KVM: arm64: nv: Describe trap behaviour of MDCR_EL2.HPMN KVM: arm64: nv: Honor MDCR_EL2.{TPM, TPMCR} in Host EL0 KVM: arm64: nv: Reinject traps that take effect in Host EL0 KVM: arm64: nv: Rename BEHAVE_FORWARD_ANY KVM: arm64: nv: Allow coarse-grained trap combos to use complex traps KVM: arm64: Describe RES0/RES1 bits of MDCR_EL2 arm64: sysreg: Add new definitions for ID_AA64DFR0_EL1 arm64: sysreg: Migrate MDCR_EL2 definition to table arm64: sysreg: Describe ID_AA64DFR2_EL1 fields Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | KVM: arm64: nv: Reprogram PMU events affected by nested transitionOliver Upton2024-10-312-0/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Start reprogramming PMU events at nested boundaries now that everything is in place to handle the EL2 event filter. Only repaint events where the filter differs between EL1 and EL2 as a slight optimization. PMU now 'works' for nested VMs, albeit slow. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025182559.3364829-1-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | KVM: arm64: nv: Apply EL2 event filtering when in hyp contextOliver Upton2024-10-311-1/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It hopefully comes as no surprise when I say that vEL2 actually runs at EL1. So, the guest hypervisor's EL2 event filter (NSH) needs to actually be applied to EL1 in the perf event. In addition to this, the disable bit for the guest counter range (HPMD) needs to have the effect of stopping the affected counters. Do exactly that by stuffing ::exclude_kernel with the combined effect of these controls. This isn't quite enough yet, as the backing perf events need to be reprogrammed upon nested ERET/exception entry to remap the effective filter onto ::exclude_kernel. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025182354.3364124-18-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | KVM: arm64: nv: Honor MDCR_EL2.HLPOliver Upton2024-10-311-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Counters that fall in the hypervisor range (i.e. N >= HPMN) have a separate control for enabling 64 bit overflow. Take it into account. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025182354.3364124-17-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | KVM: arm64: nv: Honor MDCR_EL2.HPMEOliver Upton2024-10-311-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the PMU is configured with split counter ranges, HPME becomes the enable bit for the counters reserved for EL2. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025182354.3364124-16-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | KVM: arm64: Add helpers to determine if PMC counts at a given ELOliver Upton2024-10-311-12/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Checking the exception level filters for a PMC is a minor annoyance to open code. Add helpers to check if an event counts at EL0 and EL1, which will prove useful in a subsequent change. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025182354.3364124-15-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | KVM: arm64: nv: Adjust range of accessible PMCs according to HPMNOliver Upton2024-10-312-7/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The value of MDCR_EL2.HPMN controls the number of event counters made visible to EL0 and EL1. This means it is possible for the guest hypervisor to allow direct access to event counters to the L2. Rework KVM's PMU register emulation to take the effects of HPMN into account when handling a trap. For bitmask-style registers, writes only affect accessible registers. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025182354.3364124-14-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | KVM: arm64: Rename kvm_pmu_valid_counter_mask()Oliver Upton2024-10-312-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Nested PMU support requires dynamically changing the visible range of PMU counters based on the exception level and value of MDCR_EL2.HPMN. At the same time, the PMU emulation code needs to know the absolute number of implemented counters, regardless of context. Rename the existing helper to make it obvious that it returns the number of implemented counters and not anything else. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025182354.3364124-13-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | KVM: arm64: nv: Advertise support for FEAT_HPMN0Oliver Upton2024-10-311-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Everything is in place now for KVM to actually handle MDCR_EL2.HPMN. Not only that, the emulation is capable of doing FEAT_HPMN0. Advertise support for the feature in the VM's ID registers. It is possible to emulate FEAT_HPMN0 on hardware that doesn't support it since KVM currently traps all PMU registers. Having said that, let's only advertise the feature on supporting hardware in case KVM ever provides 'direct' PMU support to VMs w/o involving host perf. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025182354.3364124-12-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | KVM: arm64: nv: Describe trap behaviour of MDCR_EL2.HPMNOliver Upton2024-10-312-64/+114
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | MDCR_EL2.HPMN splits the PMU event counters into two ranges: the first range is accessible from all ELs, and the second range is accessible only to EL2/3. Supposing the guest hypervisor allows direct access to the PMU counters from the L2, KVM needs to locally handle those accesses. Add a new complex trap configuration for HPMN that checks if the counter index is accessible to the current context. As written, the architecture suggests HPMN only causes PMEVCNTR<n>_EL0 to trap, though intuition (and the pseudocode) suggest that the trap applies to PMEVTYPER<n>_EL0 as well. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025182354.3364124-11-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | KVM: arm64: nv: Honor MDCR_EL2.{TPM, TPMCR} in Host EL0Oliver Upton2024-10-311-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TPM and TPMCR trap bits also affect Host EL0. How fun. Mark these two trap bits as such and take advantage of the new infrastructure for dealing w/ EL0 traps. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025182354.3364124-10-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | KVM: arm64: nv: Reinject traps that take effect in Host EL0Oliver Upton2024-10-311-4/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Wire up the other end of traps that affect host EL0 by actually injecting them into the guest hypervisor. Skip over FGT entirely, as a cursory glance suggests no FGT is effective in host EL0. Note that kvm_inject_nested() is already equipped for handling exceptions while the VM is already in a host context. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025182354.3364124-9-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | KVM: arm64: nv: Rename BEHAVE_FORWARD_ANYOliver Upton2024-10-311-46/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BEHAVE_FORWARD_ANY is slightly ambiguous, especially since we're about to cram some more information into the enum. Rephrase it. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025182354.3364124-8-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | KVM: arm64: nv: Allow coarse-grained trap combos to use complex trapsOliver Upton2024-10-311-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KVM uses a sanity-check to avoid infinite recursion in trap combinations that could potentially depend on itself. Narrow the scope of this sanity check to the exact CGT IDs that correspond w/ trap combos, opening the door to using 'complex' traps as part of a combination. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025182354.3364124-7-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | KVM: arm64: Describe RES0/RES1 bits of MDCR_EL2Oliver Upton2024-10-311-0/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add support for sanitising MDCR_EL2 and describe the RES0/RES1 bits according to the feature set exposed to the VM. Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025182354.3364124-6-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | * | | Merge branch kvm-arm64/mmio-sea into kvmarm/nextOliver Upton2024-11-111-2/+30
| | |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * kvm-arm64/mmio-sea: : Fix for SEA injection in response to MMIO : : Fix + test coverage for SEA injection in response to an unhandled MMIO : exit to userspace. Naturally, if userspace decides to abort an MMIO : instruction KVM shouldn't continue with instruction emulation... KVM: arm64: selftests: Add tests for MMIO external abort injection KVM: arm64: selftests: Convert to kernel's ESR terminology tools: arm64: Grab a copy of esr.h from kernel KVM: arm64: Don't retire aborted MMIO instruction Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | | KVM: arm64: Don't retire aborted MMIO instructionOliver Upton2024-10-261-2/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Returning an abort to the guest for an unsupported MMIO access is a documented feature of the KVM UAPI. Nevertheless, it's clear that this plumbing has seen limited testing, since userspace can trivially cause a WARN in the MMIO return: WARNING: CPU: 0 PID: 30558 at arch/arm64/include/asm/kvm_emulate.h:536 kvm_handle_mmio_return+0x46c/0x5c4 arch/arm64/include/asm/kvm_emulate.h:536 Call trace: kvm_handle_mmio_return+0x46c/0x5c4 arch/arm64/include/asm/kvm_emulate.h:536 kvm_arch_vcpu_ioctl_run+0x98/0x15b4 arch/arm64/kvm/arm.c:1133 kvm_vcpu_ioctl+0x75c/0xa78 virt/kvm/kvm_main.c:4487 __do_sys_ioctl fs/ioctl.c:51 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x1e0/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x38/0x68 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x90/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 The splat is complaining that KVM is advancing PC while an exception is pending, i.e. that KVM is retiring the MMIO instruction despite a pending synchronous external abort. Womp womp. Fix the glaring UAPI bug by skipping over all the MMIO emulation in case there is a pending synchronous exception. Note that while userspace is capable of pending an asynchronous exception (SError, IRQ, or FIQ), it is still safe to retire the MMIO instruction in this case as (1) they are by definition asynchronous, and (2) KVM relies on hardware support for pending/delivering these exceptions instead of the software state machine for advancing PC. Cc: stable@vger.kernel.org Fixes: da345174ceca ("KVM: arm/arm64: Allow user injection of external data aborts") Reported-by: Alexander Potapenko <glider@google.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241025203106.3529261-2-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | * | | | Merge branch kvm-arm64/misc into kvmarm/nextOliver Upton2024-11-118-62/+122
| | |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * kvm-arm64/misc: : Miscellaneous updates : : - Drop useless check against vgic state in ICC_CLTR_EL1.SEIS read : emulation : : - Fix trap configuration for pKVM : : - Close the door on initialization bugs surrounding userspace irqchip : static key by removing it. KVM: selftests: Don't bother deleting memslots in KVM when freeing VMs KVM: arm64: Get rid of userspace_irqchip_in_use KVM: arm64: Initialize trap register values in hyp in pKVM KVM: arm64: Initialize the hypervisor's VM state at EL2 KVM: arm64: Refactor kvm_vcpu_enable_ptrauth() for hyp use KVM: arm64: Move pkvm_vcpu_init_traps() to init_pkvm_hyp_vcpu() KVM: arm64: Don't map 'kvm_vgic_global_state' at EL2 with pKVM KVM: arm64: Just advertise SEIS as 0 when emulating ICC_CTLR_EL1 Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | | | KVM: arm64: Get rid of userspace_irqchip_in_useRaghavendra Rao Ananta2024-10-312-17/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Improper use of userspace_irqchip_in_use led to syzbot hitting the following WARN_ON() in kvm_timer_update_irq(): WARNING: CPU: 0 PID: 3281 at arch/arm64/kvm/arch_timer.c:459 kvm_timer_update_irq+0x21c/0x394 Call trace: kvm_timer_update_irq+0x21c/0x394 arch/arm64/kvm/arch_timer.c:459 kvm_timer_vcpu_reset+0x158/0x684 arch/arm64/kvm/arch_timer.c:968 kvm_reset_vcpu+0x3b4/0x560 arch/arm64/kvm/reset.c:264 kvm_vcpu_set_target arch/arm64/kvm/arm.c:1553 [inline] kvm_arch_vcpu_ioctl_vcpu_init arch/arm64/kvm/arm.c:1573 [inline] kvm_arch_vcpu_ioctl+0x112c/0x1b3c arch/arm64/kvm/arm.c:1695 kvm_vcpu_ioctl+0x4ec/0xf74 virt/kvm/kvm_main.c:4658 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0x108/0x184 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x78/0x1b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xe8/0x1b0 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x50 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x14c arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 The following sequence led to the scenario: - Userspace creates a VM and a vCPU. - The vCPU is initialized with KVM_ARM_VCPU_PMU_V3 during KVM_ARM_VCPU_INIT. - Without any other setup, such as vGIC or vPMU, userspace issues KVM_RUN on the vCPU. Since the vPMU is requested, but not setup, kvm_arm_pmu_v3_enable() fails in kvm_arch_vcpu_run_pid_change(). As a result, KVM_RUN returns after enabling the timer, but before incrementing 'userspace_irqchip_in_use': kvm_arch_vcpu_run_pid_change() ret = kvm_arm_pmu_v3_enable() if (!vcpu->arch.pmu.created) return -EINVAL; if (ret) return ret; [...] if (!irqchip_in_kernel(kvm)) static_branch_inc(&userspace_irqchip_in_use); - Userspace ignores the error and issues KVM_ARM_VCPU_INIT again. Since the timer is already enabled, control moves through the following flow, ultimately hitting the WARN_ON(): kvm_timer_vcpu_reset() if (timer->enabled) kvm_timer_update_irq() if (!userspace_irqchip()) ret = kvm_vgic_inject_irq() ret = vgic_lazy_init() if (unlikely(!vgic_initialized(kvm))) if (kvm->arch.vgic.vgic_model != KVM_DEV_TYPE_ARM_VGIC_V2) return -EBUSY; WARN_ON(ret); Theoretically, since userspace_irqchip_in_use's functionality can be simply replaced by '!irqchip_in_kernel()', get rid of the static key to avoid the mismanagement, which also helps with the syzbot issue. Cc: <stable@vger.kernel.org> Reported-by: syzbot <syzkaller@googlegroups.com> Suggested-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Raghavendra Rao Ananta <rananta@google.com> Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | | | KVM: arm64: Initialize trap register values in hyp in pKVMFuad Tabba2024-10-312-1/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Handle the initialization of trap registers at the hypervisor in pKVM, even for non-protected guests. The host is not trusted with the values of the trap registers, regardless of the VM type. Therefore, when switching between the host and the guests, only flush the HCR_EL2 TWI and TWE bits. The host is allowed to configure these for opportunistic scheduling, as neither affects the protection of VMs or the hypervisor. Reported-by: Will Deacon <will@kernel.org> Fixes: 814ad8f96e92 ("KVM: arm64: Drop trapping of PAuth instructions/keys") Signed-off-by: Fuad Tabba <tabba@google.com> Link: https://lore.kernel.org/r/20241018074833.2563674-5-tabba@google.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | | | KVM: arm64: Initialize the hypervisor's VM state at EL2Fuad Tabba2024-10-311-0/+77
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Do not trust the state of the VM as provided by the host when initializing the hypervisor's view of the VM sate. Initialize it instead at EL2 to a known good and safe state, as pKVM already does with hypervisor VCPU states. Signed-off-by: Fuad Tabba <tabba@google.com> Link: https://lore.kernel.org/r/20241018074833.2563674-4-tabba@google.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | | | KVM: arm64: Refactor kvm_vcpu_enable_ptrauth() for hyp useFuad Tabba2024-10-311-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move kvm_vcpu_enable_ptrauth() to a shared header to be used by hypervisor code in protected mode. No functional change intended. Signed-off-by: Fuad Tabba <tabba@google.com> Link: https://lore.kernel.org/r/20241018074833.2563674-3-tabba@google.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | | | KVM: arm64: Move pkvm_vcpu_init_traps() to init_pkvm_hyp_vcpu()Fuad Tabba2024-10-314-19/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move pkvm_vcpu_init_traps() to the initialization of the hypervisor's vcpu state in init_pkvm_hyp_vcpu(), and remove the associated hypercall. In protected mode, traps need to be initialized whenever a VCPU is initialized anyway, and not only for protected VMs. This also saves an unnecessary hypercall. Signed-off-by: Fuad Tabba <tabba@google.com> Link: https://lore.kernel.org/r/20241018074833.2563674-2-tabba@google.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | | | KVM: arm64: Don't map 'kvm_vgic_global_state' at EL2 with pKVMWill Deacon2024-10-241-17/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that 'kvm_vgic_global_state' is no longer needed for ICC_CTLR_EL1 emulation on machines with a broken SEIS implementation, drop the pKVM hypervisor mapping of the page. Note that kvm_vgic_global_state is still mapped in non-protected hypervisor configurations (i.e. {n,h}VHE) through the rodata section mapping. Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Signed-off-by: Will Deacon <will@kernel.org> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241022144016.27350-3-will@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | | | KVM: arm64: Just advertise SEIS as 0 when emulating ICC_CTLR_EL1Will Deacon2024-10-241-3/+0
| | | |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ICC_CTLR_EL1 accesses from a guest are trapped and emulated on systems with broken SEIS support and without FEAT_GICv3_TDIR. On such systems, we mask SEIS support in 'kvm_vgic_global_state.ich_vtr_el2' and so the value of ICC_CTLR_EL1.SEIS visible to the guest is always zero. Simplify the ICC_CTLR_EL1 read emulation to return 0 for the SEIS field, rather than reading an always-zero value from the global state. Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Signed-off-by: Will Deacon <will@kernel.org> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241022144016.27350-2-will@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | * | | | Merge branch kvm-arm64/mpam-ni into kvmarm/nextOliver Upton2024-11-112-33/+157
| | |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * kvm-arm64/mpam-ni: : Hiding FEAT_MPAM from KVM guests, courtesy of James Morse + Joey Gouly : : Fix a longstanding bug where FEAT_MPAM was accidentally exposed to KVM : guests + the EL2 trap configuration was not explicitly configured. As : part of this, bring in skeletal support for initialising the MPAM CPU : context so KVM can actually set traps for its guests. : : Be warned -- if this series leads to boot failures on your system, : you're running on turd firmware. : : As an added bonus (that builds upon the infrastructure added by the MPAM : series), allow userspace to configure CTR_EL0.L1Ip, courtesy of Shameer : Kolothum. KVM: arm64: Make L1Ip feature in CTR_EL0 writable from userspace KVM: arm64: selftests: Test ID_AA64PFR0.MPAM isn't completely ignored KVM: arm64: Disable MPAM visibility by default and ignore VMM writes KVM: arm64: Add a macro for creating filtered sys_reg_descs entries KVM: arm64: Fix missing traps of guest accesses to the MPAM registers arm64: cpufeature: discover CPU support for MPAM arm64: head.S: Initialise MPAM EL2 registers and disable traps arm64/sysreg: Convert existing MPAM sysregs and add the remaining entries Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | | | KVM: arm64: Make L1Ip feature in CTR_EL0 writable from userspaceShameer Kolothum2024-11-111-4/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Only allow userspace to set VIPT(0b10) or PIPT(0b11) for L1Ip based on what hardware reports as both AIVIVT (0b01) and VPIPT (0b00) are documented as reserved. Using a VIPT for Guest where hardware reports PIPT may lead to over invalidation, but is still correct. Hence, we can allow downgrading PIPT to VIPT, but not the other way around. Reviewed-by: Sebastian Ott <sebott@redhat.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Link: https://lore.kernel.org/r/20241022073943.35764-1-shameerali.kolothum.thodi@huawei.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | | | KVM: arm64: Disable MPAM visibility by default and ignore VMM writesJames Morse2024-10-311-3/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 011e5f5bf529f ("arm64/cpufeature: Add remaining feature bits in ID_AA64PFR0 register") exposed the MPAM field of AA64PFR0_EL1 to guests, but didn't add trap handling. A previous patch supplied the missing trap handling. Existing VMs that have the MPAM field of ID_AA64PFR0_EL1 set need to be migratable, but there is little point enabling the MPAM CPU interface on new VMs until there is something a guest can do with it. Clear the MPAM field from the guest's ID_AA64PFR0_EL1 and on hardware that supports MPAM, politely ignore the VMMs attempts to set this bit. Guests exposed to this bug have the sanitised value of the MPAM field, so only the correct value needs to be ignored. This means the field can continue to be used to block migration to incompatible hardware (between MPAM=1 and MPAM=5), and the VMM can't rely on the field being ignored. Signed-off-by: James Morse <james.morse@arm.com> Co-developed-by: Joey Gouly <joey.gouly@arm.com> Signed-off-by: Joey Gouly <joey.gouly@arm.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241030160317.2528209-7-joey.gouly@arm.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| | | * | | | KVM: arm64: Add a macro for creating filtered sys_reg_descs entriesJames Morse2024-10-311-28/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The sys_reg_descs array holds function pointers and reset value for managing the user-space and guest view of system registers. These are mostly created by a set of macro's as only some combinations of behaviour are needed. If a register needs special treatment, its sys_reg_descs entry is open-coded. This is true of some id registers where the value provided by user-space is validated by some helpers. Before adding another one of these, add a helper that covers the existing special cases. 'ID_FILTERED' expects helpers to set the user-space value, and retrieve the modified reset value. Like ID_WRITABLE() this uses id_visibility(), which should have no functional change for the registers converted to use ID_FILTERED(). read_sanitised_id_aa64dfr0_el1() and read_sanitised_id_aa64pfr0_el1() have been refactored to be called from kvm_read_sanitised_id_reg(), to try be consistent with ID_WRITABLE(). Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Joey Gouly <joey.gouly@arm.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241030160317.2528209-6-joey.gouly@arm.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>