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path: root/arch/arm64/kvm/sys_regs.c
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2024-10-31KVM: arm64: Hide TCR2_EL1 from userspace when disabled for guestsMark Brown
When the guest does not support FEAT_TCR2 we should not allow any access to it in order to ensure that we do not create spurious issues with guest migration. Add a visibility operation for it. Fixes: fbff56068232 ("KVM: arm64: Save/restore TCR2_EL1") Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240822-kvm-arm64-hide-pie-regs-v2-2-376624fa829c@kernel.org [maz: simplify by using __el2_visibility(), kvm_has_tcr2() throughout] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241023145345.1613824-25-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-10-31KVM: arm64: Define helper for EL2 registers with custom visibilityMark Brown
In preparation for adding more visibility filtering for EL2 registers add a helper macro like EL2_REG() which allows specification of a custom visibility operation. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240822-kvm-arm64-hide-pie-regs-v2-1-376624fa829c@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241023145345.1613824-24-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-10-31KVM: arm64: Add a composite EL2 visibility helperMarc Zyngier
We are starting to have a bunch of visibility helpers checking for EL2 + something else, and we are going to add more. Simplify things somehow by introducing a helper that implement extractly that by taking a visibility helper as a parameter, and convert the existing ones to that. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241023145345.1613824-23-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-10-31KVM: arm64: Handle PIR{,E0}_EL2 trapsMarc Zyngier
Add the FEAT_S1PIE EL2 registers the sysreg descriptor array so that they can be handled as a trap. Access to these registers is conditional based on ID_AA64MMFR3_EL1.S1PIE being advertised. Similarly to other other changes, PIRE0_EL2 is guaranteed to trap thanks to the D22677 update to the architecture. Reviewed-by: Joey Gouly <joey.gouly@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241023145345.1613824-17-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-10-31KVM: arm64: Add PIR{,E0}_EL2 to the sysreg arraysMarc Zyngier
Add the FEAT_S1PIE EL2 registers to the per-vcpu sysreg register array. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241023145345.1613824-15-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-10-31KVM: arm64: Extend masking facility to arbitrary registersMarc Zyngier
We currently only use the masking (RES0/RES1) facility for VNCR registers, as they are memory-based and thus easy to sanitise. But we could apply the same thing to other registers if we: - split the sanitisation from __VNCR_START__ - apply the sanitisation when reading from a HW register This involves a new "marker" in the vcpu_sysreg enum, which defines the point at which the sanitisation applies (the VNCR registers being of course after this marker). Whle we are at it, rename kvm_vcpu_sanitise_vncr_reg() to kvm_vcpu_apply_reg_masks(), which is vaguely more explicit, and harden set_sysreg_masks() against setting masks for random registers... Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Joey Gouly <joey.gouly@arm.com> Link: https://lore.kernel.org/r/20241023145345.1613824-10-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-10-31KVM: arm64: Add TCR2_EL2 to the sysreg arraysMarc Zyngier
Add the TCR2_EL2 register to the per-vcpu sysreg register array, the sysreg descriptor array, and advertise it as mapped to TCR2_EL1 for NV purposes. Access to this register is conditional based on ID_AA64MMFR3_EL1.TCRX being advertised. Reviewed-by: Joey Gouly <joey.gouly@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241023145345.1613824-12-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-10-31KVM: arm64: nv: Handle CNTHCTL_EL2 speciallyMarc Zyngier
Accessing CNTHCTL_EL2 is fraught with danger if running with HCR_EL2.E2H=1: half of the bits are held in CNTKCTL_EL1, and thus can be changed behind our back, while the rest lives in the CNTHCTL_EL2 shadow copy that is memory-based. Yes, this is a lot of fun! Make sure that we merge the two on read access, while we can write to CNTKCTL_EL1 in a more straightforward manner. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241023145345.1613824-7-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-10-31KVM: arm64: nv: Add missing EL2->EL1 mappings in get_el2_to_el1_mapping()Marc Zyngier
As KVM has grown a bunch of new system register for NV, it appears that we are missing them in the get_el2_to_el1_mapping() list. Most of them are not crucial as they don't tend to be accessed via vcpu_read_sys_reg() and vcpu_write_sys_reg(). Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241023145345.1613824-6-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-10-17KVM: arm64: Fix shift-out-of-bounds bugIlkka Koskinen
Fix a shift-out-of-bounds bug reported by UBSAN when running VM with MTE enabled host kernel. UBSAN: shift-out-of-bounds in arch/arm64/kvm/sys_regs.c:1988:14 shift exponent 33 is too large for 32-bit type 'int' CPU: 26 UID: 0 PID: 7629 Comm: qemu-kvm Not tainted 6.12.0-rc2 #34 Hardware name: IEI NF5280R7/Mitchell MB, BIOS 00.00. 2024-10-12 09:28:54 10/14/2024 Call trace: dump_backtrace+0xa0/0x128 show_stack+0x20/0x38 dump_stack_lvl+0x74/0x90 dump_stack+0x18/0x28 __ubsan_handle_shift_out_of_bounds+0xf8/0x1e0 reset_clidr+0x10c/0x1c8 kvm_reset_sys_regs+0x50/0x1c8 kvm_reset_vcpu+0xec/0x2b0 __kvm_vcpu_set_target+0x84/0x158 kvm_vcpu_set_target+0x138/0x168 kvm_arch_vcpu_ioctl_vcpu_init+0x40/0x2b0 kvm_arch_vcpu_ioctl+0x28c/0x4b8 kvm_vcpu_ioctl+0x4bc/0x7a8 __arm64_sys_ioctl+0xb4/0x100 invoke_syscall+0x70/0x100 el0_svc_common.constprop.0+0x48/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x3c/0x158 el0t_64_sync_handler+0x120/0x130 el0t_64_sync+0x194/0x198 Fixes: 7af0c2534f4c ("KVM: arm64: Normalize cache configuration") Cc: stable@vger.kernel.org Reviewed-by: Gavin Shan <gshan@redhat.com> Signed-off-by: Ilkka Koskinen <ilkka@os.amperecomputing.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20241017025701.67936-1-ilkka@os.amperecomputing.com Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-10-08KVM: arm64: Expose S1PIE to guestsMark Brown
Prior to commit 70ed7238297f ("KVM: arm64: Sanitise ID_AA64MMFR3_EL1") we just exposed the santised view of ID_AA64MMFR3_EL1 to guests, meaning that they saw both TCRX and S1PIE if present on the host machine. That commit added VMM control over the contents of the register and exposed S1POE but removed S1PIE, meaning that the extension is no longer visible to guests. Reenable support for S1PIE with VMM control. Fixes: 70ed7238297f ("KVM: arm64: Sanitise ID_AA64MMFR3_EL1") Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Joey Gouly <joey.gouly@arm.com> Link: https://lore.kernel.org/r/20241005-kvm-arm64-fix-s1pie-v1-1-5901f02de749@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-10-08KVM: arm64: nv: Clarify safety of allowing TLBI unmaps to rescheduleOliver Upton
There's been a decent amount of attention around unmaps of nested MMUs, and TLBI handling is no exception to this. Add a comment clarifying why it is safe to reschedule during a TLBI unmap, even without a reference on the MMU in progress. Signed-off-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20241007233028.2236133-5-oliver.upton@linux.dev Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-10-08KVM: arm64: nv: Do not block when unmapping stage-2 if disallowedOliver Upton
Right now the nested code allows unmap operations on a shadow stage-2 to block unconditionally. This is wrong in a couple places, such as a non-blocking MMU notifier or on the back of a sched_in() notifier as part of shadow MMU recycling. Carry through whether or not blocking is allowed to kvm_pgtable_stage2_unmap(). This 'fixes' an issue where stage-2 MMU reclaim would precipitate a stack overflow from a pile of kvm_sched_in() callbacks, all trying to recycle a stage-2 MMU. Signed-off-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20241007233028.2236133-3-oliver.upton@linux.dev Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-10-08Merge branch kvm-arm64/idregs-6.12 into kvmarm/fixesMarc Zyngier
* kvm-arm64/idregs-6.12: : . : Make some fields of ID_AA64DFR0_EL1 and ID_AA64PFR1_EL1 : writable from userspace, so that a VMM can influence the : set of guest-visible features. : : - for ID_AA64DFR0_EL1: DoubleLock, WRPs, PMUVer and DebugVer : are writable (courtesy of Shameer Kolothum) : : - for ID_AA64PFR1_EL1: BT, SSBS, CVS2_frac are writable : (courtesy of Shaoqin Huang) : . KVM: selftests: aarch64: Add writable test for ID_AA64PFR1_EL1 KVM: arm64: Allow userspace to change ID_AA64PFR1_EL1 KVM: arm64: Use kvm_has_feat() to check if FEAT_SSBS is advertised to the guest KVM: arm64: Disable fields that KVM doesn't know how to handle in ID_AA64PFR1_EL1 KVM: arm64: Make the exposed feature bits in AA64DFR0_EL1 writable from userspace Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-09-16Merge tag 'for-linus-non-x86' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "These are the non-x86 changes (mostly ARM, as is usually the case). The generic and x86 changes will come later" ARM: - New Stage-2 page table dumper, reusing the main ptdump infrastructure - FP8 support - Nested virtualization now supports the address translation (FEAT_ATS1A) family of instructions - Add selftest checks for a bunch of timer emulation corner cases - Fix multiple cases where KVM/arm64 doesn't correctly handle the guest trying to use a GICv3 that wasn't advertised - Remove REG_HIDDEN_USER from the sysreg infrastructure, making things little simpler - Prevent MTE tags being restored by userspace if we are actively logging writes, as that's a recipe for disaster - Correct the refcount on a page that is not considered for MTE tag copying (such as a device) - When walking a page table to split block mappings, synchronize only at the end the walk rather than on every store - Fix boundary check when transfering memory using FFA - Fix pKVM TLB invalidation, only affecting currently out of tree code but worth addressing for peace of mind LoongArch: - Revert qspinlock to test-and-set simple lock on VM. - Add Loongson Binary Translation extension support. - Add PMU support for guest. - Enable paravirt feature control from VMM. - Implement function kvm_para_has_feature(). RISC-V: - Fix sbiret init before forwarding to userspace - Don't zero-out PMU snapshot area before freeing data - Allow legacy PMU access from guest - Fix to allow hpmcounter31 from the guest" * tag 'for-linus-non-x86' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (64 commits) LoongArch: KVM: Implement function kvm_para_has_feature() LoongArch: KVM: Enable paravirt feature control from VMM LoongArch: KVM: Add PMU support for guest KVM: arm64: Get rid of REG_HIDDEN_USER visibility qualifier KVM: arm64: Simplify visibility handling of AArch32 SPSR_* KVM: arm64: Simplify handling of CNTKCTL_EL12 LoongArch: KVM: Add vm migration support for LBT registers LoongArch: KVM: Add Binary Translation extension support LoongArch: KVM: Add VM feature detection function LoongArch: Revert qspinlock to test-and-set simple lock on VM KVM: arm64: Register ptdump with debugfs on guest creation arm64: ptdump: Don't override the level when operating on the stage-2 tables arm64: ptdump: Use the ptdump description from a local context arm64: ptdump: Expose the attribute parsing functionality KVM: arm64: Add memory length checks and remove inline in do_ffa_mem_xfer KVM: arm64: Move pagetable definitions to common header KVM: arm64: nv: Add support for FEAT_ATS1A KVM: arm64: nv: Plumb handling of AT S1* traps from EL2 KVM: arm64: nv: Make AT+PAN instructions aware of FEAT_PAN3 KVM: arm64: nv: Sanitise SCTLR_EL1.EPAN according to VM configuration ...
2024-09-16Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "The highlights are support for Arm's "Permission Overlay Extension" using memory protection keys, support for running as a protected guest on Android as well as perf support for a bunch of new interconnect PMUs. Summary: ACPI: - Enable PMCG erratum workaround for HiSilicon HIP10 and 11 platforms. - Ensure arm64-specific IORT header is covered by MAINTAINERS. CPU Errata: - Enable workaround for hardware access/dirty issue on Ampere-1A cores. Memory management: - Define PHYSMEM_END to fix a crash in the amdgpu driver. - Avoid tripping over invalid kernel mappings on the kexec() path. - Userspace support for the Permission Overlay Extension (POE) using protection keys. Perf and PMUs: - Add support for the "fixed instruction counter" extension in the CPU PMU architecture. - Extend and fix the event encodings for Apple's M1 CPU PMU. - Allow LSM hooks to decide on SPE permissions for physical profiling. - Add support for the CMN S3 and NI-700 PMUs. Confidential Computing: - Add support for booting an arm64 kernel as a protected guest under Android's "Protected KVM" (pKVM) hypervisor. Selftests: - Fix vector length issues in the SVE/SME sigreturn tests - Fix build warning in the ptrace tests. Timers: - Add support for PR_{G,S}ET_TSC so that 'rr' can deal with non-determinism arising from the architected counter. Miscellaneous: - Rework our IPI-based CPU stopping code to try NMIs if regular IPIs don't succeed. - Minor fixes and cleanups" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (94 commits) perf: arm-ni: Fix an NULL vs IS_ERR() bug arm64: hibernate: Fix warning for cast from restricted gfp_t arm64: esr: Define ESR_ELx_EC_* constants as UL arm64: pkeys: remove redundant WARN perf: arm_pmuv3: Use BR_RETIRED for HW branch event if enabled MAINTAINERS: List Arm interconnect PMUs as supported perf: Add driver for Arm NI-700 interconnect PMU dt-bindings/perf: Add Arm NI-700 PMU perf/arm-cmn: Improve format attr printing perf/arm-cmn: Clean up unnecessary NUMA_NO_NODE check arm64/mm: use lm_alias() with addresses passed to memblock_free() mm: arm64: document why pte is not advanced in contpte_ptep_set_access_flags() arm64: Expose the end of the linear map in PHYSMEM_END arm64: trans_pgd: mark PTEs entries as valid to avoid dead kexec() arm64/mm: Delete __init region from memblock.reserved perf/arm-cmn: Support CMN S3 dt-bindings: perf: arm-cmn: Add CMN S3 perf/arm-cmn: Refactor DTC PMU register access perf/arm-cmn: Make cycle counts less surprising perf/arm-cmn: Improve build-time assertion ...
2024-09-12Merge branch 'for-next/poe' into for-next/coreWill Deacon
* for-next/poe: (31 commits) arm64: pkeys: remove redundant WARN kselftest/arm64: Add test case for POR_EL0 signal frame records kselftest/arm64: parse POE_MAGIC in a signal frame kselftest/arm64: add HWCAP test for FEAT_S1POE selftests: mm: make protection_keys test work on arm64 selftests: mm: move fpregs printing kselftest/arm64: move get_header() arm64: add Permission Overlay Extension Kconfig arm64: enable PKEY support for CPUs with S1POE arm64: enable POE and PIE to coexist arm64/ptrace: add support for FEAT_POE arm64: add POE signal support arm64: implement PKEYS support arm64: add pte_access_permitted_no_overlay() arm64: handle PKEY/POE faults arm64: mask out POIndex when modifying a PTE arm64: convert protection key into vm_flags and pgprot values arm64: add POIndex defines arm64: re-order MTE VM_ flags arm64: enable the Permission Overlay Extension for EL0 ...
2024-09-12Merge branch kvm-arm64/visibility-cleanups into kvmarm-master/nextMarc Zyngier
* kvm-arm64/visibility-cleanups: : . : Remove REG_HIDDEN_USER from the sysreg infrastructure, making things : a little more simple. From the cover letter: : : "Since 4d4f52052ba8 ("KVM: arm64: nv: Drop EL12 register traps that are : redirected to VNCR") and the admission that KVM would never be supporting : the original FEAT_NV, REG_HIDDEN_USER only had a few users, all of which : could either be replaced by a more ad-hoc mechanism, or removed altogether." : . KVM: arm64: Get rid of REG_HIDDEN_USER visibility qualifier KVM: arm64: Simplify visibility handling of AArch32 SPSR_* KVM: arm64: Simplify handling of CNTKCTL_EL12 Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-09-12Merge branch kvm-arm64/nv-at-pan into kvmarm-master/nextMarc Zyngier
* kvm-arm64/nv-at-pan: : . : Add NV support for the AT family of instructions, which mostly results : in adding a page table walker that deals with most of the complexity : of the architecture. : : From the cover letter: : : "Another task that a hypervisor supporting NV on arm64 has to deal with : is to emulate the AT instruction, because we multiplex all the S1 : translations on a single set of registers, and the guest S2 is never : truly resident on the CPU. : : So given that we lie about page tables, we also have to lie about : translation instructions, hence the emulation. Things are made : complicated by the fact that guest S1 page tables can be swapped out, : and that our shadow S2 is likely to be incomplete. So while using AT : to emulate AT is tempting (and useful), it is not going to always : work, and we thus need a fallback in the shape of a SW S1 walker." : . KVM: arm64: nv: Add support for FEAT_ATS1A KVM: arm64: nv: Plumb handling of AT S1* traps from EL2 KVM: arm64: nv: Make AT+PAN instructions aware of FEAT_PAN3 KVM: arm64: nv: Sanitise SCTLR_EL1.EPAN according to VM configuration KVM: arm64: nv: Add SW walker for AT S1 emulation KVM: arm64: nv: Make ps_to_output_size() generally available KVM: arm64: nv: Add emulation of AT S12E{0,1}{R,W} KVM: arm64: nv: Add basic emulation of AT S1E2{R,W} KVM: arm64: nv: Add basic emulation of AT S1E1{R,W}P KVM: arm64: nv: Add basic emulation of AT S1E{0,1}{R,W} KVM: arm64: nv: Honor absence of FEAT_PAN2 KVM: arm64: nv: Turn upper_attr for S2 walk into the full descriptor KVM: arm64: nv: Enforce S2 alignment when contiguous bit is set arm64: Add ESR_ELx_FSC_ADDRSZ_L() helper arm64: Add system register encoding for PSTATE.PAN arm64: Add PAR_EL1 field description arm64: Add missing APTable and TCR_ELx.HPD masks KVM: arm64: Make kvm_at() take an OP_AT_* Signed-off-by: Marc Zyngier <maz@kernel.org> # Conflicts: # arch/arm64/kvm/nested.c
2024-09-12Merge branch kvm-arm64/vgic-sre-traps into kvmarm-master/nextMarc Zyngier
* kvm-arm64/vgic-sre-traps: : . : Fix the multiple of cases where KVM/arm64 doesn't correctly : handle the guest trying to use a GICv3 that isn't advertised. : : From the cover letter: : : "It recently appeared that, when running on a GICv3-equipped platform : (which is what non-ancient arm64 HW has), *not* configuring a GICv3 : for the guest could result in less than desirable outcomes. : : We have multiple issues to fix: : : - for registers that *always* trap (the SGI registers) or that *may* : trap (the SRE register), we need to check whether a GICv3 has been : instantiated before acting upon the trap. : : - for registers that only conditionally trap, we must actively trap : them even in the absence of a GICv3 being instantiated, and handle : those traps accordingly. : : - finally, ID registers must reflect the absence of a GICv3, so that : we are consistent. : : This series goes through all these requirements. The main complexity : here is to apply a GICv3 configuration on the host in the absence of a : GICv3 in the guest. This is pretty hackish, but I don't have a much : better solution so far. : : As part of making wider use of of the trap bits, we fully define the : trap routing as per the architecture, something that we eventually : need for NV anyway." : . KVM: arm64: selftests: Cope with lack of GICv3 in set_id_regs KVM: arm64: Add selftest checking how the absence of GICv3 is handled KVM: arm64: Unify UNDEF injection helpers KVM: arm64: Make most GICv3 accesses UNDEF if they trap KVM: arm64: Honor guest requested traps in GICv3 emulation KVM: arm64: Add trap routing information for ICH_HCR_EL2 KVM: arm64: Add ICH_HCR_EL2 to the vcpu state KVM: arm64: Zero ID_AA64PFR0_EL1.GIC when no GICv3 is presented to the guest KVM: arm64: Add helper for last ditch idreg adjustments KVM: arm64: Force GICv3 trap activation when no irqchip is configured on VHE KVM: arm64: Force SRE traps when SRE access is not enabled KVM: arm64: Move GICv3 trap configuration to kvm_calculate_traps() Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-09-12Merge branch kvm-arm64/fpmr into kvmarm-master/nextMarc Zyngier
* kvm-arm64/fpmr: : . : Add FP8 support to the KVM/arm64 floating point handling. : : This includes new ID registers (ID_AA64PFR2_EL1 ID_AA64FPFR0_EL1) : being made visible to guests, as well as a new confrol register : (FPMR) which gets context-switched. : . KVM: arm64: Expose ID_AA64PFR2_EL1 to userspace and guests KVM: arm64: Enable FP8 support when available and configured KVM: arm64: Expose ID_AA64FPFR0_EL1 as a writable ID reg KVM: arm64: Honor trap routing for FPMR KVM: arm64: Add save/restore support for FPMR KVM: arm64: Move FPMR into the sysreg array KVM: arm64: Add predicate for FPMR support in a VM KVM: arm64: Move SVCR into the sysreg array Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-09-11KVM: arm64: Get rid of REG_HIDDEN_USER visibility qualifierMarc Zyngier
Now that REG_HIDDEN_USER has no direct user anymore, remove it entirely and update all users of sysreg_hidden_user() to call sysreg_hidden() instead. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240904082419.1982402-4-maz@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-09-11KVM: arm64: Simplify visibility handling of AArch32 SPSR_*Marc Zyngier
Since SPSR_* are not associated with any register in the sysreg array, nor do they have .get_user()/.set_user() helpers, they are invisible to userspace with that encoding. Therefore hidden_user_visibility() serves no purpose here, and can be safely removed. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240904082419.1982402-3-maz@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-09-11KVM: arm64: Simplify handling of CNTKCTL_EL12Marc Zyngier
We go trough a great deal of effort to map CNTKCTL_EL12 to CNTKCTL_EL1 while hidding this mapping from userspace via a special visibility helper. However, it would be far simpler to just provide an accessor doing the mapping job, removing the need for a visibility helper. With that done, we can also remove the EL12_REG() macro which serves no purpose. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240904082419.1982402-2-maz@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-09-04KVM: arm64: Sanitise ID_AA64MMFR3_EL1Joey Gouly
Add the missing sanitisation of ID_AA64MMFR3_EL1, making sure we solely expose S1POE and TCRX (we currently don't support anything else). [joey: Took Marc's patch for S1PIE, and changed it for S1POE] Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Joey Gouly <joey.gouly@arm.com> Link: https://lore.kernel.org/r/20240822151113.1479789-11-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-09-04KVM: arm64: Save/restore POE registersJoey Gouly
Define the new system registers that POE introduces and context switch them. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20240822151113.1479789-8-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-08-30KVM: arm64: nv: Add support for FEAT_ATS1AMarc Zyngier
Handling FEAT_ATS1A (which provides the AT S1E{1,2}A instructions) is pretty easy, as it is just the usual AT without the permission check. This basically amounts to plumbing the instructions in the various dispatch tables, and handling FEAT_ATS1A being disabled in the ID registers. Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-30KVM: arm64: nv: Plumb handling of AT S1* traps from EL2Marc Zyngier
Hooray, we're done. Plug the AT traps into the system instruction table, and let it rip. Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-30KVM: arm64: nv: Honor absence of FEAT_PAN2Marc Zyngier
If our guest has been configured without PAN2, make sure that AT S1E1{R,W}P will generate an UNDEF. Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-27KVM: arm64: Unify UNDEF injection helpersMarc Zyngier
We currently have two helpers (undef_access() and trap_undef()) that do exactly the same thing: inject an UNDEF and return 'false' (as an indication that PC should not be incremented). We definitely could do with one less. Given that undef_access() is used 80ish times, while trap_undef() is only used 30 times, the latter loses the battle and is immediately sacrificed. We also have a large number of instances where undef_access() is open-coded. Let's also convert those. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240827152517.3909653-11-maz@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-27KVM: arm64: Make most GICv3 accesses UNDEF if they trapMarc Zyngier
We don't expect to trap any GICv3 register for host handling, apart from ICC_SRE_EL1 and the SGI registers. If they trap, that's because the guest is playing with us despite being told it doesn't have a GICv3. If it does, UNDEF is what it will get. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240827152517.3909653-10-maz@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-27KVM: arm64: Add ICH_HCR_EL2 to the vcpu stateMarc Zyngier
As we are about to describe the trap routing for ICH_HCR_EL2, add the register to the vcpu state in its VNCR form, as well as reset Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240827152517.3909653-7-maz@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-27KVM: arm64: Zero ID_AA64PFR0_EL1.GIC when no GICv3 is presented to the guestMarc Zyngier
In order to be consistent, we shouldn't advertise a GICv3 when none is actually usable by the guest. Wipe the feature when these conditions apply, and allow the field to be written from userspace. This now allows us to rewrite the kvm_has_gicv3 helper() in terms of kvm_has_feat(), given that it is always evaluated at runtime. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240827152517.3909653-6-maz@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-27KVM: arm64: Add helper for last ditch idreg adjustmentsMarc Zyngier
We already have to perform a set of last-chance adjustments for NV purposes. We will soon have to do the same for the GIC, so introduce a helper for that exact purpose. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240827152517.3909653-5-maz@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-27KVM: arm64: Move GICv3 trap configuration to kvm_calculate_traps()Marc Zyngier
Follow the pattern introduced with vcpu_set_hcr(), and introduce vcpu_set_ich_hcr(), which configures the GICv3 traps at the same point. This will allow future changes to introduce trap configuration on a per-VM basis. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240827152517.3909653-2-maz@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-27KVM: arm64: Expose ID_AA64PFR2_EL1 to userspace and guestsMarc Zyngier
Everything is now in place for a guest to "enjoy" FP8 support. Expose ID_AA64PFR2_EL1 to both userspace and guests, with the explicit restriction of only being able to clear FPMR. All other features (MTE* at the time of writing) are hidden and not writable. Reviewed-by: Mark Brown <broonie@kernel.org> Tested-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240820131802.3547589-9-maz@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-27KVM: arm64: Enable FP8 support when available and configuredMarc Zyngier
If userspace has enabled FP8 support (by setting ID_AA64PFR2_EL1.FPMR to 1), let's enable the feature by setting HCRX_EL2.EnFPM for the vcpu. Reviewed-by: Mark Brown <broonie@kernel.org> Tested-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240820131802.3547589-8-maz@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-27KVM: arm64: Expose ID_AA64FPFR0_EL1 as a writable ID regMarc Zyngier
ID_AA64FPFR0_EL1 contains all sort of bits that contain a description of which FP8 subfeatures are implemented. We don't really care about them, so let's just expose that register and allow userspace to disable subfeatures at will. Reviewed-by: Mark Brown <broonie@kernel.org> Tested-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240820131802.3547589-7-maz@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-27KVM: arm64: Move FPMR into the sysreg arrayMarc Zyngier
Just like SVCR, FPMR is currently stored at the wrong location. Let's move it where it belongs. Reviewed-by: Mark Brown <broonie@kernel.org> Tested-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240820131802.3547589-4-maz@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-27KVM: arm64: Move SVCR into the sysreg arrayMarc Zyngier
SVCR is just a system register, and has no purpose being outside of the sysreg array. If anything, it only makes it more difficult to eventually support SME one day. If ever. Move it into the array with its little friends, and associate it with a visibility predicate. Although this is dead code, it at least paves the way for the next set of FP-related extensions. Reviewed-by: Mark Brown <broonie@kernel.org> Tested-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20240820131802.3547589-2-maz@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-25KVM: arm64: Allow userspace to change ID_AA64PFR1_EL1Shaoqin Huang
Allow userspace to change the guest-visible value of the register with different way of handling: - Since the RAS and MPAM is not writable in the ID_AA64PFR0_EL1 register, RAS_frac and MPAM_frac are also not writable in the ID_AA64PFR1_EL1 register. - The MTE is controlled by a separate UAPI (KVM_CAP_ARM_MTE) with an internal flag (KVM_ARCH_FLAG_MTE_ENABLED). So it's not writable. - For those fields which KVM doesn't know how to handle, they are not exposed to the guest (being disabled in the register read accessor), those fields value will always be 0. Those fields don't have a known behavior now, so don't advertise them to the userspace. Thus still not writable. Those fields include SME, RNDR_trap, NMI, GCS, THE, DF2, PFAR, MTE_frac, MTEX. - The BT, SSBS, CSV2_frac don't introduce any new registers which KVM doesn't know how to handle, they can be written without ill effect. So let them writable. Besides, we don't do the crosscheck in KVM about the CSV2_frac even if it depends on the value of CSV2, it should be made sure by the VMM instead of KVM. Signed-off-by: Shaoqin Huang <shahuang@redhat.com> Link: https://lore.kernel.org/r/20240723072004.1470688-4-shahuang@redhat.com Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-25KVM: arm64: Disable fields that KVM doesn't know how to handle in ↵Shaoqin Huang
ID_AA64PFR1_EL1 For some of the fields in the ID_AA64PFR1_EL1 register, KVM doesn't know how to handle them right now. So explicitly disable them in the register accessor, then those fields value will be masked to 0 even if on the hardware the field value is 1. This is safe because from a UAPI point of view that read_sanitised_ftr_reg() doesn't yet return a nonzero value for any of those fields. This will benifit the migration if the host and VM have different values when restoring a VM. Those fields include RNDR_trap, NMI, MTE_frac, GCS, THE, MTEX, DF2, PFAR. Signed-off-by: Shaoqin Huang <shahuang@redhat.com> Link: https://lore.kernel.org/r/20240723072004.1470688-2-shahuang@redhat.com Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-22KVM: arm64: Make the exposed feature bits in AA64DFR0_EL1 writable from ↵Shameer Kolothum
userspace KVM exposes the OS double lock feature bit to Guests but returns RAZ/WI on Guest OSDLR_EL1 access. This breaks Guest migration between systems where this feature differ. Add support to make this feature writable from userspace by setting the mask bit. While at it, set the mask bits for the exposed WRPs(Number of Watchpoints) as well. Also update the selftest to cover these fields. However we still can't make BRPs and CTX_CMPs fields writable, because as per ARM ARM DDI 0487K.a, section D2.8.3 Breakpoint types and linking of breakpoints, highest numbered breakpoints(BRPs) must be context aware breakpoints(CTX_CMPs). KVM does not trap + emulate the breakpoint registers, and as such cannot support a layout that misaligns with the underlying hardware. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Link: https://lore.kernel.org/r/20240816132819.34316-1-shameerali.kolothum.thodi@huawei.com Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-22KVM: arm64: Make ICC_*SGI*_EL1 undef in the absence of a vGICv3Marc Zyngier
On a system with a GICv3, if a guest hasn't been configured with GICv3 and that the host is not capable of GICv2 emulation, a write to any of the ICC_*SGI*_EL1 registers is trapped to EL2. We therefore try to emulate the SGI access, only to hit a NULL pointer as no private interrupt is allocated (no GIC, remember?). The obvious fix is to give the guest what it deserves, in the shape of a UNDEF exception. Reported-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/20240820100349.3544850-2-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-08-16arm64: perf/kvm: Use a common PMU cycle counter defineRob Herring (Arm)
The PMUv3 and KVM code each have a define for the PMU cycle counter index. Move KVM's define to a shared location and use it for PMUv3 driver. Reviewed-by: Marc Zyngier <maz@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Rob Herring (Arm) <robh@kernel.org> Tested-by: James Clark <james.clark@linaro.org> Link: https://lore.kernel.org/r/20240731-arm-pmu-3-9-icntr-v3-5-280a8d7ff465@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2024-08-16KVM: arm64: pmu: Use generated define for PMSELR_EL0.SEL accessRob Herring (Arm)
ARMV8_PMU_COUNTER_MASK is really a mask for the PMSELR_EL0.SEL register field. Make that clear by adding a standard sysreg definition for the register, and using it instead. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Rob Herring (Arm) <robh@kernel.org> Tested-by: James Clark <james.clark@linaro.org> Link: https://lore.kernel.org/r/20240731-arm-pmu-3-9-icntr-v3-4-280a8d7ff465@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2024-07-14Merge branch kvm-arm64/nv-tcr2 into kvmarm/nextOliver Upton
* kvm-arm64/nv-tcr2: : Fixes to the handling of TCR_EL1, courtesy of Marc Zyngier : : Series addresses a couple gaps that are present in KVM (from cover : letter): : : - VM configuration: HCRX_EL2.TCR2En is forced to 1, and we blindly : save/restore stuff. : : - trap bit description and routing: none, obviously, since we make a : point in not trapping. KVM: arm64: Honor trap routing for TCR2_EL1 KVM: arm64: Make PIR{,E0}_EL1 save/restore conditional on FEAT_TCRX KVM: arm64: Make TCR2_EL1 save/restore dependent on the VM features KVM: arm64: Get rid of HCRX_GUEST_FLAGS KVM: arm64: Correctly honor the presence of FEAT_TCRX Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-07-14Merge branch kvm-arm64/nv-sve into kvmarm/nextOliver Upton
* kvm-arm64/nv-sve: : CPTR_EL2, FPSIMD/SVE support for nested : : This series brings support for honoring the guest hypervisor's CPTR_EL2 : trap configuration when running a nested guest, along with support for : FPSIMD/SVE usage at L1 and L2. KVM: arm64: Allow the use of SVE+NV KVM: arm64: nv: Add additional trap setup for CPTR_EL2 KVM: arm64: nv: Add trap description for CPTR_EL2 KVM: arm64: nv: Add TCPAC/TTA to CPTR->CPACR conversion helper KVM: arm64: nv: Honor guest hypervisor's FP/SVE traps in CPTR_EL2 KVM: arm64: nv: Load guest FP state for ZCR_EL2 trap KVM: arm64: nv: Handle CPACR_EL1 traps KVM: arm64: Spin off helper for programming CPTR traps KVM: arm64: nv: Ensure correct VL is loaded before saving SVE state KVM: arm64: nv: Use guest hypervisor's max VL when running nested guest KVM: arm64: nv: Save guest's ZCR_EL2 when in hyp context KVM: arm64: nv: Load guest hyp's ZCR into EL1 state KVM: arm64: nv: Handle ZCR_EL2 traps KVM: arm64: nv: Forward SVE traps to guest hypervisor KVM: arm64: nv: Forward FP/ASIMD traps to guest hypervisor Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-07-14Merge branch kvm-arm64/ctr-el0 into kvmarm/nextOliver Upton
* kvm-arm64/ctr-el0: : Support for user changes to CTR_EL0, courtesy of Sebastian Ott : : Allow userspace to change the guest-visible value of CTR_EL0 for a VM, : so long as the requested value represents a subset of features supported : by hardware. In other words, prevent the VMM from over-promising the : capabilities of hardware. : : Make this happen by fitting CTR_EL0 into the existing infrastructure for : feature ID registers. KVM: selftests: Assert that MPIDR_EL1 is unchanged across vCPU reset KVM: arm64: nv: Unfudge ID_AA64PFR0_EL1 masking KVM: selftests: arm64: Test writes to CTR_EL0 KVM: arm64: rename functions for invariant sys regs KVM: arm64: show writable masks for feature registers KVM: arm64: Treat CTR_EL0 as a VM feature ID register KVM: arm64: unify code to prepare traps KVM: arm64: nv: Use accessors for modifying ID registers KVM: arm64: Add helper for writing ID regs KVM: arm64: Use read-only helper for reading VM ID registers KVM: arm64: Make idregs debugfs iterator search sysreg table directly KVM: arm64: Get sys_reg encoding from descriptor in idregs_debug_show() Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-06-27KVM: arm64: Get rid of HCRX_GUEST_FLAGSMarc Zyngier
HCRX_GUEST_FLAGS gives random KVM hackers the impression that they can stuff bits in this macro and unconditionally enable features in the guest. In general, this is wrong (we have been there with FEAT_MOPS, and again with FEAT_TCRX). Document that HCRX_EL2.SMPME is an exception rather than the rule, and get rid of HCRX_GUEST_FLAGS. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Joey Gouly <joey.gouly@arm.com> Link: https://lore.kernel.org/r/20240625130042.259175-3-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>