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2023-02-13Merge branch kvm-arm64/nv-prefix into kvmarm/nextOliver Upton
* kvm-arm64/nv-prefix: : Preamble to NV support, courtesy of Marc Zyngier. : : This brings in a set of prerequisite patches for supporting nested : virtualization in KVM/arm64. Of course, there is a long way to go until : NV is actually enabled in KVM. : : - Introduce cpucap / vCPU feature flag to pivot the NV code on : : - Add support for EL2 vCPU register state : : - Basic nested exception handling : : - Hide unsupported features from the ID registers for NV-capable VMs KVM: arm64: nv: Use reg_to_encoding() to get sysreg ID KVM: arm64: nv: Only toggle cache for virtual EL2 when SCTLR_EL2 changes KVM: arm64: nv: Filter out unsupported features from ID regs KVM: arm64: nv: Emulate EL12 register accesses from the virtual EL2 KVM: arm64: nv: Allow a sysreg to be hidden from userspace only KVM: arm64: nv: Emulate PSTATE.M for a guest hypervisor KVM: arm64: nv: Add accessors for SPSR_EL1, ELR_EL1 and VBAR_EL1 from virtual EL2 KVM: arm64: nv: Handle SMCs taken from virtual EL2 KVM: arm64: nv: Handle trapped ERET from virtual EL2 KVM: arm64: nv: Inject HVC exceptions to the virtual EL2 KVM: arm64: nv: Support virtual EL2 exceptions KVM: arm64: nv: Handle HCR_EL2.NV system register traps KVM: arm64: nv: Add nested virt VCPU primitives for vEL2 VCPU state KVM: arm64: nv: Add EL2 system registers to vcpu context KVM: arm64: nv: Allow userspace to set PSR_MODE_EL2x KVM: arm64: nv: Reset VCPU to EL2 registers if VCPU nested virt is set KVM: arm64: nv: Introduce nested virtualization VCPU feature KVM: arm64: Use the S2 MMU context to iterate over S2 table arm64: Add ARM64_HAS_NESTED_VIRT cpufeature Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-02-13Merge branch kvm-arm64/virtual-cache-geometry into kvmarm/nextOliver Upton
* kvm-arm64/virtual-cache-geometry: : Virtualized cache geometry for KVM guests, courtesy of Akihiko Odaki. : : KVM/arm64 has always exposed the host cache geometry directly to the : guest, even though non-secure software should never perform CMOs by : Set/Way. This was slightly wrong, as the cache geometry was derived from : the PE on which the vCPU thread was running and not a sanitized value. : : All together this leads to issues migrating VMs on heterogeneous : systems, as the cache geometry saved/restored could be inconsistent. : : KVM/arm64 now presents 1 level of cache with 1 set and 1 way. The cache : geometry is entirely controlled by userspace, such that migrations from : older kernels continue to work. KVM: arm64: Mark some VM-scoped allocations as __GFP_ACCOUNT KVM: arm64: Normalize cache configuration KVM: arm64: Mask FEAT_CCIDX KVM: arm64: Always set HCR_TID2 arm64/cache: Move CLIDR macro definitions arm64/sysreg: Add CCSIDR2_EL1 arm64/sysreg: Convert CCSIDR_EL1 to automatic generation arm64: Allow the definition of UNKNOWN system register fields Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-02-11KVM: arm64: nv: Emulate PSTATE.M for a guest hypervisorMarc Zyngier
We can no longer blindly copy the VCPU's PSTATE into SPSR_EL2 and return to the guest and vice versa when taking an exception to the hypervisor, because we emulate virtual EL2 in EL1 and therefore have to translate the mode field from EL2 to EL1 and vice versa. This requires keeping track of the state we enter the guest, for which we transiently use a dedicated flag. Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230209175820.1939006-15-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-01-12KVM: arm64: Always set HCR_TID2Akihiko Odaki
Always set HCR_TID2 to trap CTR_EL0, CCSIDR2_EL1, CLIDR_EL1, and CSSELR_EL1. This saves a few lines of code and allows to employ their access trap handlers for more purposes anticipated by the old condition for setting HCR_TID2. Suggested-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com> Reviewed-by: Reiji Watanabe <reijiw@google.com> Link: https://lore.kernel.org/r/20230112023852.42012-6-akihiko.odaki@daynix.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-01-03KVM: arm64: Convert FSC_* over to ESR_ELx_FSC_*Marc Zyngier
The former is an AArch32 legacy, so let's move over to the verbose (and strictly identical) version. This involves moving some of the #defines that were private to KVM into the more generic esr.h. Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-12-05Merge branch kvm-arm64/pkvm-vcpu-state into kvmarm-master/nextMarc Zyngier
* kvm-arm64/pkvm-vcpu-state: (25 commits) : . : Large drop of pKVM patches from Will Deacon and co, adding : a private vm/vcpu state at EL2, managed independently from : the EL1 state. From the cover letter: : : "This is version six of the pKVM EL2 state series, extending the pKVM : hypervisor code so that it can dynamically instantiate and manage VM : data structures without the host being able to access them directly. : These structures consist of a hyp VM, a set of hyp vCPUs and the stage-2 : page-table for the MMU. The pages used to hold the hypervisor structures : are returned to the host when the VM is destroyed." : . KVM: arm64: Use the pKVM hyp vCPU structure in handle___kvm_vcpu_run() KVM: arm64: Don't unnecessarily map host kernel sections at EL2 KVM: arm64: Explicitly map 'kvm_vgic_global_state' at EL2 KVM: arm64: Maintain a copy of 'kvm_arm_vmid_bits' at EL2 KVM: arm64: Unmap 'kvm_arm_hyp_percpu_base' from the host KVM: arm64: Return guest memory from EL2 via dedicated teardown memcache KVM: arm64: Instantiate guest stage-2 page-tables at EL2 KVM: arm64: Consolidate stage-2 initialisation into a single function KVM: arm64: Add generic hyp_memcache helpers KVM: arm64: Provide I-cache invalidation by virtual address at EL2 KVM: arm64: Initialise hypervisor copies of host symbols unconditionally KVM: arm64: Add per-cpu fixmap infrastructure at EL2 KVM: arm64: Instantiate pKVM hypervisor VM and vCPU structures from EL1 KVM: arm64: Add infrastructure to create and track pKVM instances at EL2 KVM: arm64: Rename 'host_kvm' to 'host_mmu' KVM: arm64: Add hyp_spinlock_t static initializer KVM: arm64: Include asm/kvm_mmu.h in nvhe/mem_protect.h KVM: arm64: Add helpers to pin memory shared with the hypervisor at EL2 KVM: arm64: Prevent the donation of no-map pages KVM: arm64: Implement do_donate() helper for donating memory ... Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-11-11KVM: arm64: Use the pKVM hyp vCPU structure in handle___kvm_vcpu_run()Will Deacon
As a stepping stone towards deprivileging the host's access to the guest's vCPU structures, introduce some naive flush/sync routines to copy most of the host vCPU into the hyp vCPU on vCPU run and back again on return to EL1. This allows us to run using the pKVM hyp structures when KVM is initialised in protected mode. Tested-by: Vincent Donnefort <vdonnefort@google.com> Co-developed-by: Fuad Tabba <tabba@google.com> Signed-off-by: Fuad Tabba <tabba@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-27-will@kernel.org
2022-11-11KVM: arm64: Return guest memory from EL2 via dedicated teardown memcacheQuentin Perret
Rather than relying on the host to free the previously-donated pKVM hypervisor VM pages explicitly on teardown, introduce a dedicated teardown memcache which allows the host to reclaim guest memory resources without having to keep track of all of the allocations made by the pKVM hypervisor at EL2. Tested-by: Vincent Donnefort <vdonnefort@google.com> Co-developed-by: Fuad Tabba <tabba@google.com> Signed-off-by: Fuad Tabba <tabba@google.com> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Will Deacon <will@kernel.org> [maz: dropped __maybe_unused from unmap_donated_memory_noclear()] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-21-will@kernel.org
2022-11-11KVM: arm64: Instantiate guest stage-2 page-tables at EL2Quentin Perret
Extend the initialisation of guest data structures within the pKVM hypervisor at EL2 so that we instantiate a memory pool and a full 'struct kvm_s2_mmu' structure for each VM, with a stage-2 page-table entirely independent from the one managed by the host at EL1. The 'struct kvm_pgtable_mm_ops' used by the page-table code is populated with a set of callbacks that can manage guest pages in the hypervisor without any direct intervention from the host, allocating page-table pages from the provided pool and returning these to the host on VM teardown. To keep things simple, the stage-2 MMU for the guest is configured identically to the host stage-2 in the VTCR register and so the IPA size of the guest must match the PA size of the host. For now, the new page-table is unused as there is no way for the host to map anything into it. Yet. Tested-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-20-will@kernel.org
2022-11-11KVM: arm64: Add generic hyp_memcache helpersQuentin Perret
The host at EL1 and the pKVM hypervisor at EL2 will soon need to exchange memory pages dynamically for creating and destroying VM state. Indeed, the hypervisor will rely on the host to donate memory pages it can use to create guest stage-2 page-tables and to store VM and vCPU metadata. In order to ease this process, introduce a 'struct hyp_memcache' which is essentially a linked list of available pages, indexed by physical addresses so that it can be passed meaningfully between the different virtual address spaces configured at EL1 and EL2. Tested-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-18-will@kernel.org
2022-11-11KVM: arm64: Add per-cpu fixmap infrastructure at EL2Quentin Perret
Mapping pages in a guest page-table from within the pKVM hypervisor at EL2 may require cache maintenance to ensure that the initialised page contents is visible even to non-cacheable (e.g. MMU-off) accesses from the guest. In preparation for performing this maintenance at EL2, introduce a per-vCPU fixmap which allows the pKVM hypervisor to map guest pages temporarily into its stage-1 page-table for the purposes of cache maintenance and, in future, poisoning on the reclaim path. The use of a fixmap avoids the need for memory allocation or locking on the map() path. Tested-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Quentin Perret <qperret@google.com> Co-developed-by: Will Deacon <will@kernel.org> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-15-will@kernel.org
2022-11-11KVM: arm64: Add infrastructure to create and track pKVM instances at EL2Fuad Tabba
Introduce a global table (and lock) to track pKVM instances at EL2, and provide hypercalls that can be used by the untrusted host to create and destroy pKVM VMs and their vCPUs. pKVM VM/vCPU state is directly accessible only by the trusted hypervisor (EL2). Each pKVM VM is directly associated with an untrusted host KVM instance, and is referenced by the host using an opaque handle. Future patches will provide hypercalls to allow the host to initialize/set/get pKVM VM/vCPU state using the opaque handle. Tested-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Fuad Tabba <tabba@google.com> Co-developed-by: Will Deacon <will@kernel.org> Signed-off-by: Will Deacon <will@kernel.org> [maz: silence warning on unmap_donated_memory_noclear()] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-13-will@kernel.org
2022-11-11KVM: arm64: Rename 'host_kvm' to 'host_mmu'Will Deacon
In preparation for introducing VM and vCPU state at EL2, rename the existing 'struct host_kvm' and its singleton 'host_kvm' instance to 'host_mmu' so as to avoid confusion between the structure tracking the host stage-2 MMU state and the host instance of a 'struct kvm' for a protected guest. Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Tested-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-12-will@kernel.org
2022-11-11KVM: arm64: Add hyp_spinlock_t static initializerFuad Tabba
Introduce a static initializer macro for 'hyp_spinlock_t' so that it is straightforward to instantiate global locks at EL2. This will be later utilised for locking the VM table in the hypervisor. Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Tested-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Fuad Tabba <tabba@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-11-will@kernel.org
2022-11-11KVM: arm64: Include asm/kvm_mmu.h in nvhe/mem_protect.hWill Deacon
nvhe/mem_protect.h refers to __load_stage2() in the definition of __load_host_stage2() but doesn't include the relevant header. Include asm/kvm_mmu.h in nvhe/mem_protect.h so that users of the latter don't have to do this themselves. Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Tested-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-10-will@kernel.org
2022-11-11KVM: arm64: Add helpers to pin memory shared with the hypervisor at EL2Quentin Perret
Add helpers allowing the hypervisor to check whether a range of pages are currently shared by the host, and 'pin' them if so by blocking host unshare operations until the memory has been unpinned. This will allow the hypervisor to take references on host-provided data-structures (e.g. 'struct kvm') with the guarantee that these pages will remain in a stable state until the hypervisor decides to release them, for example during guest teardown. Tested-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-9-will@kernel.org
2022-11-11KVM: arm64: Implement do_donate() helper for donating memoryWill Deacon
Transferring ownership information of a memory region from one component to another can be achieved using a "donate" operation, which results in the previous owner losing access to the underlying pages entirely and the new owner having exclusive access to the page. Implement a do_donate() helper, along the same lines as do_{un,}share, and provide this functionality for the host-{to,from}-hyp cases as this will later be used to donate/reclaim memory pages to store VM metadata at EL2. In a similar manner to the sharing transitions, permission checks are performed by the hypervisor to ensure that the component initiating the transition really is the owner of the page and also that the completer does not currently have a page mapped at the target address. Tested-by: Vincent Donnefort <vdonnefort@google.com> Co-developed-by: Quentin Perret <qperret@google.com> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-7-will@kernel.org
2022-11-11KVM: arm64: Unify identifiers used to distinguish host and hypervisorWill Deacon
The 'pkvm_component_id' enum type provides constants to refer to the host and the hypervisor, yet this information is duplicated by the 'pkvm_hyp_id' constant. Remove the definition of 'pkvm_hyp_id' and move the 'pkvm_component_id' type definition to 'mem_protect.h' so that it can be used outside of the memory protection code, for example when initialising the owner for hypervisor-owned pages. Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Tested-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-6-will@kernel.org
2022-11-11KVM: arm64: Back the hypervisor 'struct hyp_page' array for all memoryQuentin Perret
The EL2 'vmemmap' array in nVHE Protected mode is currently very sparse: only memory pages owned by the hypervisor itself have a matching 'struct hyp_page'. However, as the size of this struct has been reduced significantly since its introduction, it appears that we can now afford to back the vmemmap for all of memory. Having an easily accessible 'struct hyp_page' for every physical page in memory provides the hypervisor with a simple mechanism to store metadata (e.g. a refcount) that wouldn't otherwise fit in the very limited number of software bits available in the host stage-2 page-table entries. This will be used in subsequent patches when pinning host memory pages for use by the hypervisor at EL2. Tested-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-4-will@kernel.org
2022-11-11KVM: arm64: Move hyp refcount manipulation helpers to common header fileQuentin Perret
We will soon need to manipulate 'struct hyp_page' refcounts from outside page_alloc.c, so move the helpers to a common header file to allow them to be reused easily. Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Tested-by: Vincent Donnefort <vdonnefort@google.com> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-2-will@kernel.org
2022-11-01KVM: arm64: Fix SMPRI_EL1/TPIDR2_EL0 trapping on VHEMarc Zyngier
The trapping of SMPRI_EL1 and TPIDR2_EL0 currently only really work on nVHE, as only this mode uses the fine-grained trapping that controls these two registers. Move the trapping enable/disable code into __{de,}activate_traps_common(), allowing it to be called when it actually matters on VHE, and remove the flipping of EL2 control for TPIDR2_EL0, which only affects the host access of this register. Fixes: 861262ab8627 ("KVM: arm64: Handle SME host state when running guests") Reported-by: Mark Brown <broonie@kernel.org> Reviewed-by: Mark Brown <broonie@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/86bkpqer4z.wl-maz@kernel.org
2022-09-09arm64/sysreg: Standardise naming for ID_AA64PFR0_EL1.AdvSIMD constantsMark Brown
The architecture refers to the register field identifying advanced SIMD as AdvSIMD but the kernel refers to it as ASIMD. Use the architecture's naming. No functional changes. Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20220905225425.1871461-15-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09arm64/sysreg: Standardise naming for ID_AA64PFR0_EL1 constantsMark Brown
We generally refer to the baseline feature implemented as _IMP so in preparation for automatic generation of register defines update those for ID_AA64PFR0_EL1 to reflect this. In the case of ASIMD we don't actually use the define so just remove it. No functional changes. Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20220905225425.1871461-14-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09arm64/sysreg: Standardise naming for ID_AA64MMFR2_EL1.CnPMark Brown
The kernel refers to ID_AA64MMFR2_EL1.CnP as CNP. In preparation for automatic generation of defines for the system registers bring the naming used by the kernel in sync with that of DDI0487H.a. No functional change. Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20220905225425.1871461-13-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09arm64/sysreg: Standardise naming for ID_AA64MMFR1_EL1 fieldsKristina Martsenko
In preparation for converting the ID_AA64MMFR1_EL1 system register defines to automatic generation, rename them to follow the conventions used by other automatically generated registers: * Add _EL1 in the register name. * Rename fields to match the names in the ARM ARM: * LOR -> LO * HPD -> HPDS * VHE -> VH * HADBS -> HAFDBS * SPECSEI -> SpecSEI * VMIDBITS -> VMIDBits There should be no functional change as a result of this patch. Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20220905225425.1871461-11-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09arm64/sysreg: Standardise naming of ID_AA64MMFR0_EL1.ASIDBitsMark Brown
For some reason we refer to ID_AA64MMFR0_EL1.ASIDBits as ASID. Add BITS into the name, bringing the naming into sync with DDI0487H.a. Due to the large amount of MixedCase in this register which isn't really consistent with either the kernel style or the majority of the architecture the use of upper case is preserved. No functional changes. Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20220905225425.1871461-10-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09arm64/sysreg: Standardise naming of ID_AA64MMFR0_EL1.BigEndMark Brown
For some reason we refer to ID_AA64MMFR0_EL1.BigEnd as BIGENDEL. Remove the EL from the name, bringing the naming into sync with DDI0487H.a. Due to the large amount of MixedCase in this register which isn't really consistent with either the kernel style or the majority of the architecture the use of upper case is preserved. No functional changes. Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20220905225425.1871461-9-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09arm64/sysreg: Add _EL1 into ID_AA64PFR1_EL1 constant namesMark Brown
Our standard is to include the _EL1 in the constant names for registers but we did not do that for ID_AA64PFR1_EL1, update to do so in preparation for conversion to automatic generation. No functional change. Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20220905225425.1871461-8-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09arm64/sysreg: Add _EL1 into ID_AA64PFR0_EL1 definition namesMark Brown
Normally we include the full register name in the defines for fields within registers but this has not been followed for ID registers. In preparation for automatic generation of defines add the _EL1s into the defines for ID_AA64PFR0_EL1 to follow the convention. No functional changes. Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20220905225425.1871461-7-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09arm64/sysreg: Add _EL1 into ID_AA64MMFR2_EL1 definition namesMark Brown
Normally we include the full register name in the defines for fields within registers but this has not been followed for ID registers. In preparation for automatic generation of defines add the _EL1s into the defines for ID_AA64MMFR2_EL1 to follow the convention. No functional changes. Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20220905225425.1871461-6-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09arm64/sysreg: Add _EL1 into ID_AA64MMFR0_EL1 definition namesMark Brown
Normally we include the full register name in the defines for fields within registers but this has not been followed for ID registers. In preparation for automatic generation of defines add the _EL1s into the defines for ID_AA64MMFR0_EL1 to follow the convention. No functional changes. Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20220905225425.1871461-5-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-08-04Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "Quite a large pull request due to a selftest API overhaul and some patches that had come in too late for 5.19. ARM: - Unwinder implementations for both nVHE modes (classic and protected), complete with an overflow stack - Rework of the sysreg access from userspace, with a complete rewrite of the vgic-v3 view to allign with the rest of the infrastructure - Disagregation of the vcpu flags in separate sets to better track their use model. - A fix for the GICv2-on-v3 selftest - A small set of cosmetic fixes RISC-V: - Track ISA extensions used by Guest using bitmap - Added system instruction emulation framework - Added CSR emulation framework - Added gfp_custom flag in struct kvm_mmu_memory_cache - Added G-stage ioremap() and iounmap() functions - Added support for Svpbmt inside Guest s390: - add an interface to provide a hypervisor dump for secure guests - improve selftests to use TAP interface - enable interpretive execution of zPCI instructions (for PCI passthrough) - First part of deferred teardown - CPU Topology - PV attestation - Minor fixes x86: - Permit guests to ignore single-bit ECC errors - Intel IPI virtualization - Allow getting/setting pending triple fault with KVM_GET/SET_VCPU_EVENTS - PEBS virtualization - Simplify PMU emulation by just using PERF_TYPE_RAW events - More accurate event reinjection on SVM (avoid retrying instructions) - Allow getting/setting the state of the speaker port data bit - Refuse starting the kvm-intel module if VM-Entry/VM-Exit controls are inconsistent - "Notify" VM exit (detect microarchitectural hangs) for Intel - Use try_cmpxchg64 instead of cmpxchg64 - Ignore benign host accesses to PMU MSRs when PMU is disabled - Allow disabling KVM's "MONITOR/MWAIT are NOPs!" behavior - Allow NX huge page mitigation to be disabled on a per-vm basis - Port eager page splitting to shadow MMU as well - Enable CMCI capability by default and handle injected UCNA errors - Expose pid of vcpu threads in debugfs - x2AVIC support for AMD - cleanup PIO emulation - Fixes for LLDT/LTR emulation - Don't require refcounted "struct page" to create huge SPTEs - Miscellaneous cleanups: - MCE MSR emulation - Use separate namespaces for guest PTEs and shadow PTEs bitmasks - PIO emulation - Reorganize rmap API, mostly around rmap destruction - Do not workaround very old KVM bugs for L0 that runs with nesting enabled - new selftests API for CPUID Generic: - Fix races in gfn->pfn cache refresh; do not pin pages tracked by the cache - new selftests API using struct kvm_vcpu instead of a (vm, id) tuple" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (606 commits) selftests: kvm: set rax before vmcall selftests: KVM: Add exponent check for boolean stats selftests: KVM: Provide descriptive assertions in kvm_binary_stats_test selftests: KVM: Check stat name before other fields KVM: x86/mmu: remove unused variable RISC-V: KVM: Add support for Svpbmt inside Guest/VM RISC-V: KVM: Use PAGE_KERNEL_IO in kvm_riscv_gstage_ioremap() RISC-V: KVM: Add G-stage ioremap() and iounmap() functions KVM: Add gfp_custom flag in struct kvm_mmu_memory_cache RISC-V: KVM: Add extensible CSR emulation framework RISC-V: KVM: Add extensible system instruction emulation framework RISC-V: KVM: Factor-out instruction emulation into separate sources RISC-V: KVM: move preempt_disable() call in kvm_arch_vcpu_ioctl_run RISC-V: KVM: Make kvm_riscv_guest_timer_init a void function RISC-V: KVM: Fix variable spelling mistake RISC-V: KVM: Improve ISA extension by using a bitmap KVM, x86/mmu: Fix the comment around kvm_tdp_mmu_zap_leafs() KVM: SVM: Dump Virtual Machine Save Area (VMSA) to klog KVM: x86/mmu: Treat NX as a valid SPTE bit for NPT KVM: x86: Do not block APIC write for non ICR registers ...
2022-07-05arm64/sysreg: Add _EL1 into ID_AA64ISAR2_EL1 definition namesMark Brown
Normally we include the full register name in the defines for fields within registers but this has not been followed for ID registers. In preparation for automatic generation of defines add the _EL1s into the defines for ID_AA64ISAR2_EL1 to follow the convention. No functional changes. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20220704170302.2609529-17-broonie@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2022-07-05arm64/sysreg: Add _EL1 into ID_AA64ISAR1_EL1 definition namesMark Brown
Normally we include the full register name in the defines for fields within registers but this has not been followed for ID registers. In preparation for automatic generation of defines add the _EL1s into the defines for ID_AA64ISAR1_EL1 to follow the convention. No functional changes. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20220704170302.2609529-16-broonie@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2022-06-29KVM: arm64: Move vcpu debug/SPE/TRBE flags to the input flag setMarc Zyngier
The three debug flags (which deal with the debug registers, SPE and TRBE) all are input flags to the hypervisor code. Move them into the input set and convert them to the new accessors. Reviewed-by: Fuad Tabba <tabba@google.com> Reviewed-by: Reiji Watanabe <reijiw@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-06-09KVM: arm64: Move FP state ownership from flag to a tristateMarc Zyngier
The KVM FP code uses a pair of flags to denote three states: - FP_ENABLED set: the guest owns the FP state - FP_HOST set: the host owns the FP state - FP_ENABLED and FP_HOST clear: nobody owns the FP state at all and both flags set is an illegal state, which nothing ever checks for... As it turns out, this isn't really a good match for flags, and we'd be better off if this was a simpler tristate, each state having a name that actually reflect the state: - FP_STATE_FREE - FP_STATE_HOST_OWNED - FP_STATE_GUEST_OWNED Kill the two flags, and move over to an enum encoding these three states. This results in less confusing code, and less risk of ending up in the uncharted territory of a 4th state if we forget to clear one of the two flags. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Reiji Watanabe <reijiw@google.com>
2022-06-09KVM: arm64: Drop FP_FOREIGN_STATE from the hypervisor codeMarc Zyngier
The vcpu KVM_ARM64_FP_FOREIGN_FPSTATE flag tracks the thread's own TIF_FOREIGN_FPSTATE so that we can evaluate just before running the vcpu whether it the FP regs contain something that is owned by the vcpu or not by updating the rest of the FP flags. We do this in the hypervisor code in order to make sure we're in a context where we are not interruptible. But we already have a hook in the run loop to generate this flag. We may as well update the FP flags directly and save the pointless flag tracking. Whilst we're at it, rename update_fp_enabled() to guest_owns_fp_regs() to indicate what the leftover of this helper actually do. Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Reiji Watanabe <reijiw@google.com> Reviewed-by: Mark Brown <broonie@kernel.org>
2022-05-26Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "S390: - ultravisor communication device driver - fix TEID on terminating storage key ops RISC-V: - Added Sv57x4 support for G-stage page table - Added range based local HFENCE functions - Added remote HFENCE functions based on VCPU requests - Added ISA extension registers in ONE_REG interface - Updated KVM RISC-V maintainers entry to cover selftests support ARM: - Add support for the ARMv8.6 WFxT extension - Guard pages for the EL2 stacks - Trap and emulate AArch32 ID registers to hide unsupported features - Ability to select and save/restore the set of hypercalls exposed to the guest - Support for PSCI-initiated suspend in collaboration with userspace - GICv3 register-based LPI invalidation support - Move host PMU event merging into the vcpu data structure - GICv3 ITS save/restore fixes - The usual set of small-scale cleanups and fixes x86: - New ioctls to get/set TSC frequency for a whole VM - Allow userspace to opt out of hypercall patching - Only do MSR filtering for MSRs accessed by rdmsr/wrmsr AMD SEV improvements: - Add KVM_EXIT_SHUTDOWN metadata for SEV-ES - V_TSC_AUX support Nested virtualization improvements for AMD: - Support for "nested nested" optimizations (nested vVMLOAD/VMSAVE, nested vGIF) - Allow AVIC to co-exist with a nested guest running - Fixes for LBR virtualizations when a nested guest is running, and nested LBR virtualization support - PAUSE filtering for nested hypervisors Guest support: - Decoupling of vcpu_is_preempted from PV spinlocks" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (199 commits) KVM: x86: Fix the intel_pt PMI handling wrongly considered from guest KVM: selftests: x86: Sync the new name of the test case to .gitignore Documentation: kvm: reorder ARM-specific section about KVM_SYSTEM_EVENT_SUSPEND x86, kvm: use correct GFP flags for preemption disabled KVM: LAPIC: Drop pending LAPIC timer injection when canceling the timer x86/kvm: Alloc dummy async #PF token outside of raw spinlock KVM: x86: avoid calling x86 emulator without a decoded instruction KVM: SVM: Use kzalloc for sev ioctl interfaces to prevent kernel data leak x86/fpu: KVM: Set the base guest FPU uABI size to sizeof(struct kvm_xsave) s390/uv_uapi: depend on CONFIG_S390 KVM: selftests: x86: Fix test failure on arch lbr capable platforms KVM: LAPIC: Trace LAPIC timer expiration on every vmentry KVM: s390: selftest: Test suppression indication on key prot exception KVM: s390: Don't indicate suppression on dirtying, failing memop selftests: drivers/s390x: Add uvdevice tests drivers/s390/char: Add Ultravisor io device MAINTAINERS: Update KVM RISC-V entry to cover selftests support RISC-V: KVM: Introduce ISA extension register RISC-V: KVM: Cleanup stale TLB entries when host CPU changes RISC-V: KVM: Add remote HFENCE functions based on VCPU requests ...
2022-05-20Merge branch 'for-next/esr-elx-64-bit' into for-next/coreCatalin Marinas
* for-next/esr-elx-64-bit: : Treat ESR_ELx as a 64-bit register. KVM: arm64: uapi: Add kvm_debug_exit_arch.hsr_high KVM: arm64: Treat ESR_EL2 as a 64-bit register arm64: Treat ESR_ELx as a 64-bit register arm64: compat: Do not treat syscall number as ESR_ELx for a bad syscall arm64: Make ESR_ELx_xVC_IMM_MASK compatible with assembly
2022-05-04arm64/sysreg: Standardise ID_AA64ISAR0_EL1 macro namesMark Brown
The macros for accessing fields in ID_AA64ISAR0_EL1 omit the _EL1 from the name of the register. In preparation for converting this register to be automatically generated update the names to include an _EL1, there should be no functional change. Signed-off-by: Mark Brown <broonie@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20220503170233.507788-8-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-05-04arm64: Update name of ID_AA64ISAR0_EL1_ATOMIC to reflect ARMMark Brown
The architecture reference manual refers to the field in bits 23:20 of ID_AA64ISAR0_EL1 with the name "atomic" but the kernel defines for this bitfield use the name "atomics". Bring the two into sync to make it easier to cross reference with the specification. Signed-off-by: Mark Brown <broonie@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20220503170233.507788-7-broonie@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-04-29KVM: arm64: Treat ESR_EL2 as a 64-bit registerAlexandru Elisei
ESR_EL2 was defined as a 32-bit register in the initial release of the ARM Architecture Manual for Armv8-A, and was later extended to 64 bits, with bits [63:32] RES0. ARMv8.7 introduced FEAT_LS64, which makes use of bits [36:32]. KVM treats ESR_EL1 as a 64-bit register when saving and restoring the guest context, but ESR_EL2 is handled as a 32-bit register. Start treating ESR_EL2 as a 64-bit register to allow KVM to make use of the most significant 32 bits in the future. The type chosen to represent ESR_EL2 is u64, as that is consistent with the notation KVM overwhelmingly uses today (u32), and how the rest of the registers are declared. Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220425114444.368693-5-alexandru.elisei@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-04-28KVM: arm64: Introduce pkvm_alloc_private_va_range()Kalesh Singh
pkvm_hyp_alloc_private_va_range() can be used to reserve private VA ranges in the pKVM nVHE hypervisor. Allocations are aligned based on the order of the requested size. This will be used to implement stack guard pages for pKVM nVHE hypervisor (in a subsequent patch in the series). Credits to Quentin Perret <qperret@google.com> for the idea of moving private VA allocation out of __pkvm_create_private_mapping() Signed-off-by: Kalesh Singh <kaleshsingh@google.com> Tested-by: Fuad Tabba <tabba@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220420214317.3303360-3-kaleshsingh@google.com
2022-03-24Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "ARM: - Proper emulation of the OSLock feature of the debug architecture - Scalibility improvements for the MMU lock when dirty logging is on - New VMID allocator, which will eventually help with SVA in VMs - Better support for PMUs in heterogenous systems - PSCI 1.1 support, enabling support for SYSTEM_RESET2 - Implement CONFIG_DEBUG_LIST at EL2 - Make CONFIG_ARM64_ERRATUM_2077057 default y - Reduce the overhead of VM exit when no interrupt is pending - Remove traces of 32bit ARM host support from the documentation - Updated vgic selftests - Various cleanups, doc updates and spelling fixes RISC-V: - Prevent KVM_COMPAT from being selected - Optimize __kvm_riscv_switch_to() implementation - RISC-V SBI v0.3 support s390: - memop selftest - fix SCK locking - adapter interruptions virtualization for secure guests - add Claudio Imbrenda as maintainer - first step to do proper storage key checking x86: - Continue switching kvm_x86_ops to static_call(); introduce static_call_cond() and __static_call_ret0 when applicable. - Cleanup unused arguments in several functions - Synthesize AMD 0x80000021 leaf - Fixes and optimization for Hyper-V sparse-bank hypercalls - Implement Hyper-V's enlightened MSR bitmap for nested SVM - Remove MMU auditing - Eager splitting of page tables (new aka "TDP" MMU only) when dirty page tracking is enabled - Cleanup the implementation of the guest PGD cache - Preparation for the implementation of Intel IPI virtualization - Fix some segment descriptor checks in the emulator - Allow AMD AVIC support on systems with physical APIC ID above 255 - Better API to disable virtualization quirks - Fixes and optimizations for the zapping of page tables: - Zap roots in two passes, avoiding RCU read-side critical sections that last too long for very large guests backed by 4 KiB SPTEs. - Zap invalid and defunct roots asynchronously via concurrency-managed work queue. - Allowing yielding when zapping TDP MMU roots in response to the root's last reference being put. - Batch more TLB flushes with an RCU trick. Whoever frees the paging structure now holds RCU as a proxy for all vCPUs running in the guest, i.e. to prolongs the grace period on their behalf. It then kicks the the vCPUs out of guest mode before doing rcu_read_unlock(). Generic: - Introduce __vcalloc and use it for very large allocations that need memcg accounting" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits) KVM: use kvcalloc for array allocations KVM: x86: Introduce KVM_CAP_DISABLE_QUIRKS2 kvm: x86: Require const tsc for RT KVM: x86: synthesize CPUID leaf 0x80000021h if useful KVM: x86: add support for CPUID leaf 0x80000021 KVM: x86: do not use KVM_X86_OP_OPTIONAL_RET0 for get_mt_mask Revert "KVM: x86/mmu: Zap only TDP MMU leafs in kvm_zap_gfn_range()" kvm: x86/mmu: Flush TLB before zap_gfn_range releases RCU KVM: arm64: fix typos in comments KVM: arm64: Generalise VM features into a set of flags KVM: s390: selftests: Add error memop tests KVM: s390: selftests: Add more copy memop tests KVM: s390: selftests: Add named stages for memop test KVM: s390: selftests: Add macro as abstraction for MEM_OP KVM: s390: selftests: Split memop tests KVM: s390x: fix SCK locking RISC-V: KVM: Implement SBI HSM suspend call RISC-V: KVM: Add common kvm_riscv_vcpu_wfi() function RISC-V: Add SBI HSM suspend related defines RISC-V: KVM: Implement SBI v0.3 SRST extension ...
2022-03-14Merge branch 'for-next/fpsimd' into for-next/coreWill Deacon
* for-next/fpsimd: arm64: cpufeature: Warn if we attempt to read a zero width field arm64: cpufeature: Add missing .field_width for GIC system registers arm64: signal: nofpsimd: Do not allocate fp/simd context when not available arm64: cpufeature: Always specify and use a field width for capabilities arm64: Always use individual bits in CPACR floating point enables arm64: Define CPACR_EL1_FPEN similarly to other floating point controls
2022-02-25arm64: Always use individual bits in CPACR floating point enablesMark Brown
CPACR_EL1 has several bitfields for controlling traps for floating point features to EL1, each of which has a separate bits for EL0 and EL1. Marc Zyngier noted that we are not consistent in our use of defines to manipulate these, sometimes using a define covering the whole field and sometimes using defines for the individual bits. Make this consistent by expanding the whole field defines where they are used (currently only in the KVM code) and deleting them so that no further uses can be introduced. Suggested-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Mark Brown <broonie@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20220207152109.197566-3-broonie@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2022-02-25arm64: Add support of PAuth QARMA3 architected algorithmVladimir Murzin
QARMA3 is relaxed version of the QARMA5 algorithm which expected to reduce the latency of calculation while still delivering a suitable level of security. Support for QARMA3 can be discovered via ID_AA64ISAR2_EL1 APA3, bits [15:12] Indicates whether the QARMA3 algorithm is implemented in the PE for address authentication in AArch64 state. GPA3, bits [11:8] Indicates whether the QARMA3 algorithm is implemented in the PE for generic code authentication in AArch64 state. Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220224124952.119612-4-vladimir.murzin@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2022-02-08KVM: arm64: Add some more comments in kvm_hyp_handle_fpsimd()Mark Brown
The handling for FPSIMD/SVE traps is multi stage and involves some trap manipulation which isn't quite so immediately obvious as might be desired so add a few more comments. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220124155720.3943374-3-broonie@kernel.org
2022-02-03KVM: arm64: Workaround Cortex-A510's single-step and PAC trap errataJames Morse
Cortex-A510's erratum #2077057 causes SPSR_EL2 to be corrupted when single-stepping authenticated ERET instructions. A single step is expected, but a pointer authentication trap is taken instead. The erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow EL1 to cause a return to EL2 with a guest controlled ELR_EL2. Because the conditions require an ERET into active-not-pending state, this is only a problem for the EL2 when EL2 is stepping EL1. In this case the previous SPSR_EL2 value is preserved in struct kvm_vcpu, and can be restored. Cc: stable@vger.kernel.org # 53960faf2b73: arm64: Add Cortex-A510 CPU part definition Cc: stable@vger.kernel.org Signed-off-by: James Morse <james.morse@arm.com> [maz: fixup cpucaps ordering] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220127122052.1584324-5-james.morse@arm.com
2022-02-03KVM: arm64: Avoid consuming a stale esr value when SError occurJames Morse
When any exception other than an IRQ occurs, the CPU updates the ESR_EL2 register with the exception syndrome. An SError may also become pending, and will be synchronised by KVM. KVM notes the exception type, and whether an SError was synchronised in exit_code. When an exception other than an IRQ occurs, fixup_guest_exit() updates vcpu->arch.fault.esr_el2 from the hardware register. When an SError was synchronised, the vcpu esr value is used to determine if the exception was due to an HVC. If so, ELR_EL2 is moved back one instruction. This is so that KVM can process the SError first, and re-execute the HVC if the guest survives the SError. But if an IRQ synchronises an SError, the vcpu's esr value is stale. If the previous non-IRQ exception was an HVC, KVM will corrupt ELR_EL2, causing an unrelated guest instruction to be executed twice. Check ARM_EXCEPTION_CODE() before messing with ELR_EL2, IRQs don't update this register so don't need to check. Fixes: defe21f49bc9 ("KVM: arm64: Move PC rollback on SError to HYP") Cc: stable@vger.kernel.org Reported-by: Steven Price <steven.price@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220127122052.1584324-3-james.morse@arm.com