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2022-12-09Merge tag 'kvmarm-6.2' of ↵Paolo Bonzini1-39/+51
https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for 6.2 - Enable the per-vcpu dirty-ring tracking mechanism, together with an option to keep the good old dirty log around for pages that are dirtied by something other than a vcpu. - Switch to the relaxed parallel fault handling, using RCU to delay page table reclaim and giving better performance under load. - Relax the MTE ABI, allowing a VMM to use the MAP_SHARED mapping option, which multi-process VMMs such as crosvm rely on. - Merge the pKVM shadow vcpu state tracking that allows the hypervisor to have its own view of a vcpu, keeping that state private. - Add support for the PMUv3p5 architecture revision, bringing support for 64bit counters on systems that support it, and fix the no-quite-compliant CHAIN-ed counter support for the machines that actually exist out there. - Fix a handful of minor issues around 52bit VA/PA support (64kB pages only) as a prefix of the oncoming support for 4kB and 16kB pages. - Add/Enable/Fix a bunch of selftests covering memslots, breakpoints, stage-2 faults and access tracking. You name it, we got it, we probably broke it. - Pick a small set of documentation and spelling fixes, because no good merge window would be complete without those. As a side effect, this tag also drags: - The 'kvmarm-fixes-6.1-3' tag as a dependency to the dirty-ring series - A shared branch with the arm64 tree that repaints all the system registers to match the ARM ARM's naming, and resulting in interesting conflicts
2022-12-05Merge branch kvm-arm64/pmu-unchained into kvmarm-master/nextMarc Zyngier1-0/+6
* kvm-arm64/pmu-unchained: : . : PMUv3 fixes and improvements: : : - Make the CHAIN event handling strictly follow the architecture : : - Add support for PMUv3p5 (64bit counters all the way) : : - Various fixes and cleanups : . KVM: arm64: PMU: Fix period computation for 64bit counters with 32bit overflow KVM: arm64: PMU: Sanitise PMCR_EL0.LP on first vcpu run KVM: arm64: PMU: Simplify PMCR_EL0 reset handling KVM: arm64: PMU: Replace version number '0' with ID_AA64DFR0_EL1_PMUVer_NI KVM: arm64: PMU: Make kvm_pmc the main data structure KVM: arm64: PMU: Simplify vcpu computation on perf overflow notification KVM: arm64: PMU: Allow PMUv3p5 to be exposed to the guest KVM: arm64: PMU: Implement PMUv3p5 long counter support KVM: arm64: PMU: Allow ID_DFR0_EL1.PerfMon to be set from userspace KVM: arm64: PMU: Allow ID_AA64DFR0_EL1.PMUver to be set from userspace KVM: arm64: PMU: Move the ID_AA64DFR0_EL1.PMUver limit to VM creation KVM: arm64: PMU: Do not let AArch32 change the counters' top 32 bits KVM: arm64: PMU: Simplify setting a counter to a specific value KVM: arm64: PMU: Add counter_index_to_*reg() helpers KVM: arm64: PMU: Only narrow counters that are not 64bit wide KVM: arm64: PMU: Narrow the overflow checking when required KVM: arm64: PMU: Distinguish between 64bit counter and 64bit overflow KVM: arm64: PMU: Always advertise the CHAIN event KVM: arm64: PMU: Align chained counter implementation with architecture pseudocode arm64: Add ID_DFR0_EL1.PerfMon values for PMUv3p7 and IMP_DEF Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-12-05Merge branch kvm-arm64/pkvm-vcpu-state into kvmarm-master/nextMarc Zyngier1-22/+39
* 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>
2022-12-05Merge branch kvm-arm64/dirty-ring into kvmarm-master/nextMarc Zyngier1-0/+3
* kvm-arm64/dirty-ring: : . : Add support for the "per-vcpu dirty-ring tracking with a bitmap : and sprinkles on top", courtesy of Gavin Shan. : : This branch drags the kvmarm-fixes-6.1-3 tag which was already : merged in 6.1-rc4 so that the branch is in a working state. : . KVM: Push dirty information unconditionally to backup bitmap KVM: selftests: Automate choosing dirty ring size in dirty_log_test KVM: selftests: Clear dirty ring states between two modes in dirty_log_test KVM: selftests: Use host page size to map ring buffer in dirty_log_test KVM: arm64: Enable ring-based dirty memory tracking KVM: Support dirty ring in conjunction with bitmap KVM: Move declaration of kvm_cpu_dirty_log_size() to kvm_dirty_ring.h KVM: x86: Introduce KVM_REQ_DIRTY_RING_SOFT_FULL Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-11-19KVM: arm64: PMU: Move the ID_AA64DFR0_EL1.PMUver limit to VM creationMarc Zyngier1-0/+6
As further patches will enable the selection of a PMU revision from userspace, sample the supported PMU revision at VM creation time, rather than building each time the ID_AA64DFR0_EL1 register is accessed. This shouldn't result in any change in behaviour. Reviewed-by: Reiji Watanabe <reijiw@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221113163832.3154370-11-maz@kernel.org
2022-11-11KVM: arm64: Maintain a copy of 'kvm_arm_vmid_bits' at EL2Will Deacon1-0/+1
Sharing 'kvm_arm_vmid_bits' between EL1 and EL2 allows the host to modify the variable arbitrarily, potentially leading to all sorts of shenanians as this is used to configure the VTTBR register for the guest stage-2. In preparation for unmapping host sections entirely from EL2, maintain a copy of 'kvm_arm_vmid_bits' in the pKVM hypervisor and initialise it from the host value while it is still trusted. 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/20221110190259.26861-23-will@kernel.org
2022-11-11KVM: arm64: Unmap 'kvm_arm_hyp_percpu_base' from the hostQuentin Perret1-5/+4
When pKVM is enabled, the hypervisor at EL2 does not trust the host at EL1 and must therefore prevent it from having unrestricted access to internal hypervisor state. The 'kvm_arm_hyp_percpu_base' array holds the offsets for hypervisor per-cpu allocations, so move this this into the nVHE code where it cannot be modified by the untrusted host at EL1. 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/20221110190259.26861-22-will@kernel.org
2022-11-11KVM: arm64: Consolidate stage-2 initialisation into a single functionQuentin Perret1-14/+13
The initialisation of guest stage-2 page-tables is currently split across two functions: kvm_init_stage2_mmu() and kvm_arm_setup_stage2(). That is presumably for historical reasons as kvm_arm_setup_stage2() originates from the (now defunct) KVM port for 32-bit Arm. Simplify this code path by merging both functions into one, taking care to map the 'struct kvm' into the hypervisor stage-1 early on in order to simplify the failure path. 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> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110190259.26861-19-will@kernel.org
2022-11-11KVM: arm64: Provide I-cache invalidation by virtual address at EL2Will Deacon1-0/+1
In preparation for handling cache maintenance of guest pages from within the pKVM hypervisor at EL2, introduce an EL2 copy of icache_inval_pou() which will later be plumbed into the stage-2 page-table cache maintenance callbacks, ensuring that the initial contents of pages mapped as executable into the guest stage-2 page-table is visible to the instruction fetcher. 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/20221110190259.26861-17-will@kernel.org
2022-11-11KVM: arm64: Initialise hypervisor copies of host symbols unconditionallyWill Deacon1-6/+9
The nVHE object at EL2 maintains its own copies of some host variables so that, when pKVM is enabled, the host cannot directly modify the hypervisor state. When running in normal nVHE mode, however, these variables are still mirrored at EL2 but are not initialised. Initialise the hypervisor symbols from the host copies regardless of pKVM, ensuring that any reference to this data at EL2 with normal nVHE will return a sensibly initialised value. 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/20221110190259.26861-16-will@kernel.org
2022-11-11KVM: arm64: Instantiate pKVM hypervisor VM and vCPU structures from EL1Fuad Tabba1-0/+14
With the pKVM hypervisor at EL2 now offering hypercalls to the host for creating and destroying VM and vCPU structures, plumb these in to the existing arm64 KVM backend to ensure that the hypervisor data structures are allocated and initialised on first vCPU run for a pKVM guest. In the host, 'struct kvm_protected_vm' is introduced to hold the handle of the pKVM VM instance as well as to track references to the memory donated to the hypervisor so that it can be freed back to the host allocator following VM teardown. The stage-2 page-table, hypervisor VM and vCPU structures are allocated separately so as to avoid the need for a large physically-contiguous allocation in the host at run-time. 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/20221110190259.26861-14-will@kernel.org
2022-11-10KVM: arm64: Fix kvm init failure when mode!=vhe and VA_BITS=52.Ryan Roberts1-17/+3
For nvhe and protected modes, the hyp stage 1 page-tables were previously configured to have the same number of VA bits as the kernel's idmap. However, for kernel configs with VA_BITS=52 and where the kernel is loaded in physical memory below 48 bits, the idmap VA bits is actually smaller than the kernel's normal stage 1 VA bits. This can lead to kernel addresses that can't be mapped into the hypervisor, leading to kvm initialization failure during boot: kvm [1]: IPA Size Limit: 48 bits kvm [1]: Cannot map world-switch code kvm [1]: error initializing Hyp mode: -34 Fix this by ensuring that the hyp stage 1 VA size is the maximum of what's used for the idmap and the regular kernel stage 1. At the same time, refactor the code so that the hyp VA bits is only calculated in one place. Prior to 7ba8f2b2d652, the idmap was always 52 bits for a 52 VA bits kernel and therefore the hyp stage1 was also always 52 bits. Fixes: 7ba8f2b2d652 ("arm64: mm: use a 48-bit ID map when possible on 52-bit VA builds") Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> [maz: commit message fixes] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221103150507.32948-2-ryan.roberts@arm.com
2022-11-10KVM: arm64: Enable ring-based dirty memory trackingGavin Shan1-0/+3
Enable ring-based dirty memory tracking on ARM64: - Enable CONFIG_HAVE_KVM_DIRTY_RING_ACQ_REL. - Enable CONFIG_NEED_KVM_DIRTY_RING_WITH_BITMAP. - Set KVM_DIRTY_LOG_PAGE_OFFSET for the ring buffer's physical page offset. - Add ARM64 specific kvm_arch_allow_write_without_running_vcpu() to keep the site of saving vgic/its tables out of the no-running-vcpu radar. Signed-off-by: Gavin Shan <gshan@redhat.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221110104914.31280-5-gshan@redhat.com
2022-11-09KVM: replace direct irq.h inclusionPaolo Bonzini1-0/+5
virt/kvm/irqchip.c is including "irq.h" from the arch-specific KVM source directory (i.e. not from arch/*/include) for the sole purpose of retrieving irqchip_in_kernel. Making the function inline in a header that is already included, such as asm/kvm_host.h, is not possible because it needs to look at struct kvm which is defined after asm/kvm_host.h is included. So add a kvm_arch_irqchip_in_kernel non-inline function; irqchip_in_kernel() is only performance critical on arm64 and x86, and the non-inline function is enough on all other architectures. irq.h can then be deleted from all architectures except x86. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-10-03Merge tag 'kvmarm-6.1' of ↵Paolo Bonzini1-5/+10
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for v6.1 - Fixes for single-stepping in the presence of an async exception as well as the preservation of PSTATE.SS - Better handling of AArch32 ID registers on AArch64-only systems - Fixes for the dirty-ring API, allowing it to work on architectures with relaxed memory ordering - Advertise the new kvmarm mailing list - Various minor cleanups and spelling fixes
2022-09-30Merge tag 'kvm-x86-6.1-2' of https://github.com/sean-jc/linux into HEADPaolo Bonzini1-1/+0
KVM x86 updates for 6.1, batch #2: - Misc PMU fixes and cleanups. - Fixes for Hyper-V hypercall selftest
2022-09-26KVM: remove KVM_REQ_UNHALTPaolo Bonzini1-1/+0
KVM_REQ_UNHALT is now unnecessary because it is replaced by the return value of kvm_vcpu_block/kvm_vcpu_halt. Remove it. No functional change intended. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Acked-by: Marc Zyngier <maz@kernel.org> Message-Id: <20220921003201.1441511-13-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-26KVM: arm64: Ignore kvm-arm.mode if !is_hyp_mode_available()Elliot Berman1-5/+10
Ignore kvm-arm.mode if !is_hyp_mode_available(). Specifically, we want to avoid switching kvm_mode to KVM_MODE_PROTECTED if hypervisor mode is not available. This prevents "Protected KVM" cpu capability being reported when Linux is booting in EL1 and would not have KVM enabled. Reasonably though, we should warn if the command line is requesting a KVM mode at all if KVM isn't actually available. Allow "kvm-arm.mode=none" to skip the warning since this would disable KVM anyway. Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220920190658.2880184-1-quic_eberman@quicinc.com
2022-09-19KVM: arm64: Use kmemleak_free_part_phys() to unregister hyp_mem_baseZenghui Yu1-1/+1
With commit 0c24e061196c ("mm: kmemleak: add rbtree and store physical address for objects allocated with PA"), kmemleak started to put the objects allocated with physical address onto object_phys_tree_root tree. The kmemleak_free_part() therefore no longer worked as expected on physically allocated objects (hyp_mem_base in this case) as it attempted to search and remove things in object_tree_root tree. Fix it by using kmemleak_free_part_phys() to unregister hyp_mem_base. This fixes an immediate crash when booting a KVM host in protected mode with kmemleak enabled. Signed-off-by: Zenghui Yu <yuzenghui@huawei.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220908130659.2021-1-yuzenghui@huawei.com
2022-08-19Merge tag 'kvmarm-fixes-6.0-1' of ↵Paolo Bonzini1-2/+1
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 6.0, take #1 - Fix unexpected sign extension of KVM_ARM_DEVICE_ID_MASK - Tidy-up handling of AArch32 on asymmetric systems
2022-08-17KVM: arm64: Treat PMCR_EL1.LC as RES1 on asymmetric systemsOliver Upton1-2/+1
KVM does not support AArch32 on asymmetric systems. To that end, enforce AArch64-only behavior on PMCR_EL1.LC when on an asymmetric system. Fixes: 2122a833316f ("arm64: Allow mismatched 32-bit EL0 support") Signed-off-by: Oliver Upton <oliver.upton@linux.dev> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220816192554.1455559-2-oliver.upton@linux.dev
2022-08-01Merge tag 'kvmarm-5.20' of ↵Paolo Bonzini1-13/+12
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for 5.20: - 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
2022-07-27Merge branch kvm-arm64/nvhe-stacktrace into kvmarm-master/nextMarc Zyngier1-1/+1
* kvm-arm64/nvhe-stacktrace: (27 commits) : . : Add an overflow stack to the nVHE EL2 code, allowing : the implementation of an unwinder, courtesy of : Kalesh Singh. From the cover letter (slightly edited): : : "nVHE has two modes of operation: protected (pKVM) and unprotected : (conventional nVHE). Depending on the mode, a slightly different approach : is used to dump the hypervisor stacktrace but the core unwinding logic : remains the same. : : * Protected nVHE (pKVM) stacktraces: : : In protected nVHE mode, the host cannot directly access hypervisor memory. : : The hypervisor stack unwinding happens in EL2 and is made accessible to : the host via a shared buffer. Symbolizing and printing the stacktrace : addresses is delegated to the host and happens in EL1. : : * Non-protected (Conventional) nVHE stacktraces: : : In non-protected mode, the host is able to directly access the hypervisor : stack pages. : : The hypervisor stack unwinding and dumping of the stacktrace is performed : by the host in EL1, as this avoids the memory overhead of setting up : shared buffers between the host and hypervisor." : : Additional patches from Oliver Upton and Marc Zyngier, tidying up : the initial series. : . arm64: Update 'unwinder howto' KVM: arm64: Don't open code ARRAY_SIZE() KVM: arm64: Move nVHE-only helpers into kvm/stacktrace.c KVM: arm64: Make unwind()/on_accessible_stack() per-unwinder functions KVM: arm64: Move nVHE stacktrace unwinding into its own compilation unit KVM: arm64: Move PROTECTED_NVHE_STACKTRACE around KVM: arm64: Introduce pkvm_dump_backtrace() KVM: arm64: Implement protected nVHE hyp stack unwinder KVM: arm64: Save protected-nVHE (pKVM) hyp stacktrace KVM: arm64: Stub implementation of pKVM HYP stack unwinder KVM: arm64: Allocate shared pKVM hyp stacktrace buffers KVM: arm64: Add PROTECTED_NVHE_STACKTRACE Kconfig KVM: arm64: Introduce hyp_dump_backtrace() KVM: arm64: Implement non-protected nVHE hyp stack unwinder KVM: arm64: Prepare non-protected nVHE hypervisor stacktrace KVM: arm64: Stub implementation of non-protected nVHE HYP stack unwinder KVM: arm64: On stack overflow switch to hyp overflow_stack arm64: stacktrace: Add description of stacktrace/common.h arm64: stacktrace: Factor out common unwind() arm64: stacktrace: Handle frame pointer from different address spaces ... Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-07-26KVM: arm64: Implement non-protected nVHE hyp stack unwinderKalesh Singh1-1/+1
Implements the common framework necessary for unwind() to work for non-protected nVHE mode: - on_accessible_stack() - on_overflow_stack() - unwind_next() Non-protected nVHE unwind() is used to unwind and dump the hypervisor stacktrace by the host in EL1 Signed-off-by: Kalesh Singh <kaleshsingh@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220726073750.3219117-11-kaleshsingh@google.com
2022-07-17Merge branch kvm-arm64/sysreg-cleanup-5.20 into kvmarm-master/nextMarc Zyngier1-9/+2
* kvm-arm64/sysreg-cleanup-5.20: : . : Long overdue cleanup of the sysreg userspace access, : with extra scrubbing on the vgic side of things. : From the cover letter: : : "Schspa Shi recently reported[1] that some of the vgic code interacting : with userspace was reading uninitialised stack memory, and although : that read wasn't used any further, it prompted me to revisit this part : of the code. : : Needless to say, this area of the kernel is pretty crufty, and shows a : bunch of issues in other parts of the KVM/arm64 infrastructure. This : series tries to remedy a bunch of them: : : - Sanitise the way we deal with sysregs from userspace: at the moment, : each and every .set_user/.get_user callback has to implement its own : userspace accesses (directly or indirectly). It'd be much better if : that was centralised so that we can reason about it. : : - Enforce that all AArch64 sysregs are 64bit. Always. This was sort of : implied by the code, but it took some effort to convince myself that : this was actually the case. : : - Move the vgic-v3 sysreg userspace accessors to the userspace : callbacks instead of hijacking the vcpu trap callback. This allows : us to reuse the sysreg infrastructure. : : - Consolidate userspace accesses for both GICv2, GICv3 and common code : as much as possible. : : - Cleanup a bunch of not-very-useful helpers, tidy up some of the code : as we touch it. : : [1] https://lore.kernel.org/r/m2h740zz1i.fsf@gmail.com" : . KVM: arm64: Get rid or outdated comments KVM: arm64: Descope kvm_arm_sys_reg_{get,set}_reg() KVM: arm64: Get rid of find_reg_by_id() KVM: arm64: vgic: Tidy-up calls to vgic_{get,set}_common_attr() KVM: arm64: vgic: Consolidate userspace access for base address setting KVM: arm64: vgic-v2: Add helper for legacy dist/cpuif base address setting KVM: arm64: vgic: Use {get,put}_user() instead of copy_{from.to}_user KVM: arm64: vgic-v2: Consolidate userspace access for MMIO registers KVM: arm64: vgic-v3: Consolidate userspace access for MMIO registers KVM: arm64: vgic-v3: Use u32 to manage the line level from userspace KVM: arm64: vgic-v3: Convert userspace accessors over to FIELD_GET/FIELD_PREP KVM: arm64: vgic-v3: Make the userspace accessors use sysreg API KVM: arm64: vgic-v3: Push user access into vgic_v3_cpu_sysregs_uaccess() KVM: arm64: vgic-v3: Simplify vgic_v3_has_cpu_sysregs_attr() KVM: arm64: Get rid of reg_from/to_user() KVM: arm64: Consolidate sysreg userspace accesses KVM: arm64: Rely on index_to_param() for size checks on userspace access KVM: arm64: Introduce generic get_user/set_user helpers for system registers KVM: arm64: Reorder handling of invariant sysregs from userspace KVM: arm64: Add get_reg_by_id() as a sys_reg_desc retrieving helper Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-07-17KVM: arm64: vgic-v2: Add helper for legacy dist/cpuif base address settingMarc Zyngier1-9/+2
We carry a legacy interface to set the base addresses for GICv2. As this is currently plumbed into the same handling code as the modern interface, it limits the evolution we can make there. Add a helper dedicated to this handling, with a view of maybe removing this in the future. Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-06-29Merge branch kvm-arm64/burn-the-flags into kvmarm-master/nextMarc Zyngier1-3/+9
* kvm-arm64/burn-the-flags: : . : Rework the per-vcpu flags to make them more manageable, : splitting them in different sets that have specific : uses: : : - configuration flags : - input to the world-switch : - state bookkeeping for the kernel itself : : The FP tracking is also simplified and tracked outside : of the flags as a separate state. : . KVM: arm64: Move the handling of !FP outside of the fast path KVM: arm64: Document why pause cannot be turned into a flag KVM: arm64: Reduce the size of the vcpu flag members KVM: arm64: Add build-time sanity checks for flags KVM: arm64: Warn when PENDING_EXCEPTION and INCREMENT_PC are set together KVM: arm64: Convert vcpu sysregs_loaded_on_cpu to a state flag KVM: arm64: Kill unused vcpu flags field KVM: arm64: Move vcpu WFIT flag to the state flag set KVM: arm64: Move vcpu ON_UNSUPPORTED_CPU flag to the state flag set KVM: arm64: Move vcpu SVE/SME flags to the state flag set KVM: arm64: Move vcpu debug/SPE/TRBE flags to the input flag set KVM: arm64: Move vcpu PC/Exception flags to the input flag set KVM: arm64: Move vcpu configuration flags into their own set KVM: arm64: Add three sets of flags to the vcpu state KVM: arm64: Add helpers to manipulate vcpu flags among a set KVM: arm64: Move FP state ownership from flag to a tristate KVM: arm64: Drop FP_FOREIGN_STATE from the hypervisor code Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-06-29KVM: arm64: Move the handling of !FP outside of the fast pathMarc Zyngier1-0/+6
We currently start by assuming that the host owns the FP unit at load time, then check again whether this is the case as we are about to run. Only at this point do we account for the fact that there is a (vanishingly small) chance that we're running on a system without a FPSIMD unit (yes, this is madness). We can actually move this FPSIMD check as early as load-time, and drop the check at run time. No intended change in behaviour. Suggested-by: Reiji Watanabe <reijiw@google.com> Reviewed-by: Reiji Watanabe <reijiw@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-06-29KVM: arm64: Move vcpu WFIT flag to the state flag setMarc Zyngier1-1/+1
The host kernel uses the WFIT flag to remember that a vcpu has used this instruction and wake it up as required. Move it to the state set, as nothing in the hypervisor uses this information. Reviewed-by: Fuad Tabba <tabba@google.com> Reviewed-by: Reiji Watanabe <reijiw@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-06-17KVM: arm64: Prevent kmemleak from accessing pKVM memoryQuentin Perret1-3/+3
Commit a7259df76702 ("memblock: make memblock_find_in_range method private") changed the API using which memory is reserved for the pKVM hypervisor. However, memblock_phys_alloc() differs from the original API in terms of kmemleak semantics -- the old one didn't report the reserved regions to kmemleak while the new one does. Unfortunately, when protected KVM is enabled, all kernel accesses to pKVM-private memory result in a fatal exception, which can now happen because of kmemleak scans: $ echo scan > /sys/kernel/debug/kmemleak [ 34.991354] kvm [304]: nVHE hyp BUG at: [<ffff800008fa3750>] __kvm_nvhe_handle_host_mem_abort+0x270/0x290! [ 34.991580] kvm [304]: Hyp Offset: 0xfffe8be807e00000 [ 34.991813] Kernel panic - not syncing: HYP panic: [ 34.991813] PS:600003c9 PC:0000f418011a3750 ESR:00000000f2000800 [ 34.991813] FAR:ffff000439200000 HPFAR:0000000004792000 PAR:0000000000000000 [ 34.991813] VCPU:0000000000000000 [ 34.993660] CPU: 0 PID: 304 Comm: bash Not tainted 5.19.0-rc2 #102 [ 34.994059] Hardware name: linux,dummy-virt (DT) [ 34.994452] Call trace: [ 34.994641] dump_backtrace.part.0+0xcc/0xe0 [ 34.994932] show_stack+0x18/0x6c [ 34.995094] dump_stack_lvl+0x68/0x84 [ 34.995276] dump_stack+0x18/0x34 [ 34.995484] panic+0x16c/0x354 [ 34.995673] __hyp_pgtable_total_pages+0x0/0x60 [ 34.995933] scan_block+0x74/0x12c [ 34.996129] scan_gray_list+0xd8/0x19c [ 34.996332] kmemleak_scan+0x2c8/0x580 [ 34.996535] kmemleak_write+0x340/0x4a0 [ 34.996744] full_proxy_write+0x60/0xbc [ 34.996967] vfs_write+0xc4/0x2b0 [ 34.997136] ksys_write+0x68/0xf4 [ 34.997311] __arm64_sys_write+0x20/0x2c [ 34.997532] invoke_syscall+0x48/0x114 [ 34.997779] el0_svc_common.constprop.0+0x44/0xec [ 34.998029] do_el0_svc+0x2c/0xc0 [ 34.998205] el0_svc+0x2c/0x84 [ 34.998421] el0t_64_sync_handler+0xf4/0x100 [ 34.998653] el0t_64_sync+0x18c/0x190 [ 34.999252] SMP: stopping secondary CPUs [ 35.000034] Kernel Offset: disabled [ 35.000261] CPU features: 0x800,00007831,00001086 [ 35.000642] Memory Limit: none [ 35.001329] ---[ end Kernel panic - not syncing: HYP panic: [ 35.001329] PS:600003c9 PC:0000f418011a3750 ESR:00000000f2000800 [ 35.001329] FAR:ffff000439200000 HPFAR:0000000004792000 PAR:0000000000000000 [ 35.001329] VCPU:0000000000000000 ]--- Fix this by explicitly excluding the hypervisor's memory pool from kmemleak like we already do for the hyp BSS. Cc: Mike Rapoport <rppt@kernel.org> Fixes: a7259df76702 ("memblock: make memblock_find_in_range method private") Signed-off-by: Quentin Perret <qperret@google.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220616161135.3997786-1-qperret@google.com
2022-06-10KVM: arm64: Move vcpu PC/Exception flags to the input flag setMarc Zyngier1-2/+2
The PC update flags (which also deal with exception injection) is one of the most complicated use of the flag we have. Make it more fool prof by: - moving it over to the new accessors and assign it to the input flag set - turn the combination of generic ELx flags with another flag indicating the target EL itself into an explicit set of flags for each EL and vector combination - add a new accessor to pend the exception This is otherwise a pretty straightformward conversion. 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: Ignore 'kvm-arm.mode=protected' when using VHEWill Deacon1-1/+5
Ignore 'kvm-arm.mode=protected' when using VHE so that kvm_get_mode() only returns KVM_MODE_PROTECTED on systems where the feature is available. Cc: David Brazdil <dbrazdil@google.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220609121223.2551-4-will@kernel.org
2022-06-09KVM: arm64: Return error from kvm_arch_init_vm() on allocation failureWill Deacon1-1/+3
If we fail to allocate the 'supported_cpus' cpumask in kvm_arch_init_vm() then be sure to return -ENOMEM instead of success (0) on the failure path. Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220609121223.2551-2-will@kernel.org
2022-05-26Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-30/+134
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 ...
2022-05-25Merge tag 'kvmarm-5.19' of ↵Paolo Bonzini1-27/+131
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for 5.19 - Add support for the ARMv8.6 WFxT extension - Guard pages for the EL2 stacks - Trap and emulate AArch32 ID registers to hide unsupported features - Ability to select and save/restore the set of hypercalls exposed to the guest - Support for PSCI-initiated suspend in collaboration with userspace - GICv3 register-based LPI invalidation support - Move host PMU event merging into the vcpu data structure - GICv3 ITS save/restore fixes - The usual set of small-scale cleanups and fixes [Due to the conflict, KVM_SYSTEM_EVENT_SEV_TERM is relocated from 4 to 6. - Paolo]
2022-05-23Merge tag 'arm64-upstream' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - Initial support for the ARMv9 Scalable Matrix Extension (SME). SME takes the approach used for vectors in SVE and extends this to provide architectural support for matrix operations. No KVM support yet, SME is disabled in guests. - Support for crashkernel reservations above ZONE_DMA via the 'crashkernel=X,high' command line option. - btrfs search_ioctl() fix for live-lock with sub-page faults. - arm64 perf updates: support for the Hisilicon "CPA" PMU for monitoring coherent I/O traffic, support for Arm's CMN-650 and CMN-700 interconnect PMUs, minor driver fixes, kerneldoc cleanup. - Kselftest updates for SME, BTI, MTE. - Automatic generation of the system register macros from a 'sysreg' file describing the register bitfields. - Update the type of the function argument holding the ESR_ELx register value to unsigned long to match the architecture register size (originally 32-bit but extended since ARMv8.0). - stacktrace cleanups. - ftrace cleanups. - Miscellaneous updates, most notably: arm64-specific huge_ptep_get(), avoid executable mappings in kexec/hibernate code, drop TLB flushing from get_clear_flush() (and rename it to get_clear_contig()), ARCH_NR_GPIO bumped to 2048 for ARCH_APPLE. * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (145 commits) arm64/sysreg: Generate definitions for FAR_ELx arm64/sysreg: Generate definitions for DACR32_EL2 arm64/sysreg: Generate definitions for CSSELR_EL1 arm64/sysreg: Generate definitions for CPACR_ELx arm64/sysreg: Generate definitions for CONTEXTIDR_ELx arm64/sysreg: Generate definitions for CLIDR_EL1 arm64/sve: Move sve_free() into SVE code section arm64: Kconfig.platforms: Add comments arm64: Kconfig: Fix indentation and add comments arm64: mm: avoid writable executable mappings in kexec/hibernate code arm64: lds: move special code sections out of kernel exec segment arm64/hugetlb: Implement arm64 specific huge_ptep_get() arm64/hugetlb: Use ptep_get() to get the pte value of a huge page arm64: kdump: Do not allocate crash low memory if not needed arm64/sve: Generate ZCR definitions arm64/sme: Generate defintions for SVCR arm64/sme: Generate SMPRI_EL1 definitions arm64/sme: Automatically generate SMPRIMAP_EL2 definitions arm64/sme: Automatically generate SMIDR_EL1 defines arm64/sme: Automatically generate defines for SMCR ...
2022-05-16Merge branch kvm-arm64/misc-5.19 into kvmarm-master/nextMarc Zyngier1-2/+6
* kvm-arm64/misc-5.19: : . : Misc fixes and general improvements for KVMM/arm64: : : - Better handle out of sequence sysregs in the global tables : : - Remove a couple of unnecessary loads from constant pool : : - Drop unnecessary pKVM checks : : - Add all known M1 implementations to the SEIS workaround : : - Cleanup kerneldoc warnings : . KVM: arm64: vgic-v3: List M1 Pro/Max as requiring the SEIS workaround KVM: arm64: pkvm: Don't mask already zeroed FEAT_SVE KVM: arm64: pkvm: Drop unnecessary FP/SIMD trap handler KVM: arm64: nvhe: Eliminate kernel-doc warnings KVM: arm64: Avoid unnecessary absolute addressing via literals KVM: arm64: Print emulated register table name when it is unsorted KVM: arm64: Don't BUG_ON() if emulated register table is unsorted Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16Merge branch kvm-arm64/per-vcpu-host-pmu-data into kvmarm-master/nextMarc Zyngier1-0/+2
* kvm-arm64/per-vcpu-host-pmu-data: : . : Pass the host PMU state in the vcpu to avoid the use of additional : shared memory between EL1 and EL2 (this obviously only applies : to nVHE and Protected setups). : : Patches courtesy of Fuad Tabba. : . KVM: arm64: pmu: Restore compilation when HW_PERF_EVENTS isn't selected KVM: arm64: Reenable pmu in Protected Mode KVM: arm64: Pass pmu events to hyp via vcpu KVM: arm64: Repack struct kvm_pmu to reduce size KVM: arm64: Wrapper for getting pmu_events Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16Merge branch kvm-arm64/psci-suspend into kvmarm-master/nextMarc Zyngier1-17/+87
* kvm-arm64/psci-suspend: : . : Add support for PSCI SYSTEM_SUSPEND and allow userspace to : filter the wake-up events. : : Patches courtesy of Oliver. : . Documentation: KVM: Fix title level for PSCI_SUSPEND selftests: KVM: Test SYSTEM_SUSPEND PSCI call selftests: KVM: Refactor psci_test to make it amenable to new tests selftests: KVM: Use KVM_SET_MP_STATE to power off vCPU in psci_test selftests: KVM: Create helper for making SMCCC calls selftests: KVM: Rename psci_cpu_on_test to psci_test KVM: arm64: Implement PSCI SYSTEM_SUSPEND KVM: arm64: Add support for userspace to suspend a vCPU KVM: arm64: Return a value from check_vcpu_requests() KVM: arm64: Rename the KVM_REQ_SLEEP handler KVM: arm64: Track vCPU power state using MP state values KVM: arm64: Dedupe vCPU power off helpers KVM: arm64: Don't depend on fallthrough to hide SYSTEM_RESET2 Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16Merge branch kvm-arm64/hcall-selection into kvmarm-master/nextMarc Zyngier1-0/+1
* kvm-arm64/hcall-selection: : . : Introduce a new set of virtual sysregs for userspace to : select the hypercalls it wants to see exposed to the guest. : : Patches courtesy of Raghavendra and Oliver. : . KVM: arm64: Fix hypercall bitmap writeback when vcpus have already run KVM: arm64: Hide KVM_REG_ARM_*_BMAP_BIT_COUNT from userspace Documentation: Fix index.rst after psci.rst renaming selftests: KVM: aarch64: Add the bitmap firmware registers to get-reg-list selftests: KVM: aarch64: Introduce hypercall ABI test selftests: KVM: Create helper for making SMCCC calls selftests: KVM: Rename psci_cpu_on_test to psci_test tools: Import ARM SMCCC definitions Docs: KVM: Add doc for the bitmap firmware registers Docs: KVM: Rename psci.rst to hypercalls.rst KVM: arm64: Add vendor hypervisor firmware register KVM: arm64: Add standard hypervisor firmware register KVM: arm64: Setup a framework for hypercall bitmap firmware registers KVM: arm64: Factor out firmware register handling from psci.c Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16KVM: arm64: pmu: Restore compilation when HW_PERF_EVENTS isn't selectedMarc Zyngier1-13/+0
Moving kvm_pmu_events into the vcpu (and refering to it) broke the somewhat unusual case where the kernel has no support for a PMU at all. In order to solve this, move things around a bit so that we can easily avoid refering to the pmu structure outside of PMU-aware code. As a bonus, pmu.c isn't compiled in when HW_PERF_EVENTS isn't selected. Reported-by: kernel test robot <lkp@intel.com> Reviewed-by: Fuad Tabba <tabba@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/202205161814.KQHpOzsJ-lkp@intel.com
2022-05-15KVM: arm64: Don't hypercall before EL2 initQuentin Perret1-1/+2
Will reported the following splat when running with Protected KVM enabled: [ 2.427181] ------------[ cut here ]------------ [ 2.427668] WARNING: CPU: 3 PID: 1 at arch/arm64/kvm/mmu.c:489 __create_hyp_private_mapping+0x118/0x1ac [ 2.428424] Modules linked in: [ 2.429040] CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.18.0-rc2-00084-g8635adc4efc7 #1 [ 2.429589] Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015 [ 2.430286] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 2.430734] pc : __create_hyp_private_mapping+0x118/0x1ac [ 2.431091] lr : create_hyp_exec_mappings+0x40/0x80 [ 2.431377] sp : ffff80000803baf0 [ 2.431597] x29: ffff80000803bb00 x28: 0000000000000000 x27: 0000000000000000 [ 2.432156] x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000 [ 2.432561] x23: ffffcd96c343b000 x22: 0000000000000000 x21: ffff80000803bb40 [ 2.433004] x20: 0000000000000004 x19: 0000000000001800 x18: 0000000000000000 [ 2.433343] x17: 0003e68cf7efdd70 x16: 0000000000000004 x15: fffffc81f602a2c8 [ 2.434053] x14: ffffdf8380000000 x13: ffffcd9573200000 x12: ffffcd96c343b000 [ 2.434401] x11: 0000000000000004 x10: ffffcd96c1738000 x9 : 0000000000000004 [ 2.434812] x8 : ffff80000803bb40 x7 : 7f7f7f7f7f7f7f7f x6 : 544f422effff306b [ 2.435136] x5 : 000000008020001e x4 : ffff207d80a88c00 x3 : 0000000000000005 [ 2.435480] x2 : 0000000000001800 x1 : 000000014f4ab800 x0 : 000000000badca11 [ 2.436149] Call trace: [ 2.436600] __create_hyp_private_mapping+0x118/0x1ac [ 2.437576] create_hyp_exec_mappings+0x40/0x80 [ 2.438180] kvm_init_vector_slots+0x180/0x194 [ 2.458941] kvm_arch_init+0x80/0x274 [ 2.459220] kvm_init+0x48/0x354 [ 2.459416] arm_init+0x20/0x2c [ 2.459601] do_one_initcall+0xbc/0x238 [ 2.459809] do_initcall_level+0x94/0xb4 [ 2.460043] do_initcalls+0x54/0x94 [ 2.460228] do_basic_setup+0x1c/0x28 [ 2.460407] kernel_init_freeable+0x110/0x178 [ 2.460610] kernel_init+0x20/0x1a0 [ 2.460817] ret_from_fork+0x10/0x20 [ 2.461274] ---[ end trace 0000000000000000 ]--- Indeed, the Protected KVM mode promotes __create_hyp_private_mapping() to a hypercall as EL1 no longer has access to the hypervisor's stage-1 page-table. However, the call from kvm_init_vector_slots() happens after pKVM has been initialized on the primary CPU, but before it has been initialized on secondaries. As such, if the KVM initcall procedure is migrated from one CPU to another in this window, the hypercall may end up running on a CPU for which EL2 has not been initialized. Fortunately, the pKVM hypervisor doesn't rely on the host to re-map the vectors in the private range, so the hypercall in question is in fact superfluous. Skip it when pKVM is enabled. Reported-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> [maz: simplified the checks slightly] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220513092607.35233-1-qperret@google.com
2022-05-15KVM: arm64: Pass pmu events to hyp via vcpuFuad Tabba1-0/+15
Instead of the host accessing hyp data directly, pass the pmu events of the current cpu to hyp via the vcpu. This adds 64 bits (in two fields) to the vcpu that need to be synced before every vcpu run in nvhe and protected modes. However, it isolates the hypervisor from the host, which allows us to use pmu in protected mode in a subsequent patch. No visible side effects in behavior intended. Signed-off-by: Fuad Tabba <tabba@google.com> Reviewed-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220510095710.148178-4-tabba@google.com
2022-05-04KVM: arm64: Don't BUG_ON() if emulated register table is unsortedAlexandru Elisei1-2/+6
To emulate a register access, KVM uses a table of registers sorted by register encoding to speed up queries using binary search. When Linux boots, KVM checks that the table is sorted and uses a BUG_ON() statement to let the user know if it's not. The unfortunate side effect is that an unsorted sysreg table brings down the whole kernel, not just KVM, even though the rest of the kernel can function just fine without KVM. To make matters worse, on machines which lack a serial console, the user is left pondering why the machine is taking so long to boot. Improve this situation by returning an error from kvm_arch_init() if the sysreg tables are not in the correct order. The machine is still very much usable for the user, with the exception of virtualization, who can now easily determine what went wrong. A minor typo has also been corrected in the check_sysreg_table() function. Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220428103405.70884-2-alexandru.elisei@arm.com
2022-05-04Merge branch kvm-arm64/hyp-stack-guard into kvmarm-master/nextMarc Zyngier1-3/+34
* kvm-arm64/hyp-stack-guard: : . : Harden the EL2 stack by providing stack guards, courtesy of : Kalesh Singh. : . KVM: arm64: Symbolize the nVHE HYP addresses KVM: arm64: Detect and handle hypervisor stack overflows KVM: arm64: Add guard pages for pKVM (protected nVHE) hypervisor stack KVM: arm64: Add guard pages for KVM nVHE hypervisor stack KVM: arm64: Introduce pkvm_alloc_private_va_range() KVM: arm64: Introduce hyp_alloc_private_va_range() Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-04KVM: arm64: Implement PSCI SYSTEM_SUSPENDOliver Upton1-0/+5
ARM DEN0022D.b 5.19 "SYSTEM_SUSPEND" describes a PSCI call that allows software to request that a system be placed in the deepest possible low-power state. Effectively, software can use this to suspend itself to RAM. Unfortunately, there really is no good way to implement a system-wide PSCI call in KVM. Any precondition checks done in the kernel will need to be repeated by userspace since there is no good way to protect a critical section that spans an exit to userspace. SYSTEM_RESET and SYSTEM_OFF are equally plagued by this issue, although no users have seemingly cared for the relatively long time these calls have been supported. The solution is to just make the whole implementation userspace's problem. Introduce a new system event, KVM_SYSTEM_EVENT_SUSPEND, that indicates to userspace a calling vCPU has invoked PSCI SYSTEM_SUSPEND. Additionally, add a CAP to get buy-in from userspace for this new exit type. Only advertise the SYSTEM_SUSPEND PSCI call if userspace has opted in. If a vCPU calls SYSTEM_SUSPEND, punt straight to userspace. Provide explicit documentation of userspace's responsibilites for the exit and point to the PSCI specification to describe the actual PSCI call. Reviewed-by: Reiji Watanabe <reijiw@google.com> Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220504032446.4133305-8-oupton@google.com
2022-05-04KVM: arm64: Add support for userspace to suspend a vCPUOliver Upton1-0/+51
Introduce a new MP state, KVM_MP_STATE_SUSPENDED, which indicates a vCPU is in a suspended state. In the suspended state the vCPU will block until a wakeup event (pending interrupt) is recognized. Add a new system event type, KVM_SYSTEM_EVENT_WAKEUP, to indicate to userspace that KVM has recognized one such wakeup event. It is the responsibility of userspace to then make the vCPU runnable, or leave it suspended until the next wakeup event. Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220504032446.4133305-7-oupton@google.com
2022-05-04KVM: arm64: Return a value from check_vcpu_requests()Oliver Upton1-2/+14
A subsequent change to KVM will introduce a vCPU request that could result in an exit to userspace. Change check_vcpu_requests() to return a value and document the function. Unconditionally return 1 for now. Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220504032446.4133305-6-oupton@google.com
2022-05-04KVM: arm64: Rename the KVM_REQ_SLEEP handlerOliver Upton1-2/+2
The naming of the kvm_req_sleep function is confusing: the function itself sleeps the vCPU, it does not request such an event. Rename the function to make its purpose more clear. No functional change intended. Signed-off-by: Oliver Upton <oupton@google.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220504032446.4133305-5-oupton@google.com
2022-05-04KVM: arm64: Track vCPU power state using MP state valuesOliver Upton1-10/+12
A subsequent change to KVM will add support for additional power states. Store the MP state by value rather than keeping track of it as a boolean. No functional change intended. Signed-off-by: Oliver Upton <oupton@google.com> Reviewed-by: Reiji Watanabe <reijiw@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220504032446.4133305-4-oupton@google.com