summaryrefslogtreecommitdiff
path: root/arch/arm64/kvm
AgeCommit message (Collapse)AuthorFilesLines
2022-02-01kvm/arm64: rework guest entry logicMark Rutland1-18/+33
In kvm_arch_vcpu_ioctl_run() we enter an RCU extended quiescent state (EQS) by calling guest_enter_irqoff(), and unmasked IRQs prior to exiting the EQS by calling guest_exit(). As the IRQ entry code will not wake RCU in this case, we may run the core IRQ code and IRQ handler without RCU watching, leading to various potential problems. Additionally, we do not inform lockdep or tracing that interrupts will be enabled during guest execution, which caan lead to misleading traces and warnings that interrupts have been enabled for overly-long periods. This patch fixes these issues by using the new timing and context entry/exit helpers to ensure that interrupts are handled during guest vtime but with RCU watching, with a sequence: guest_timing_enter_irqoff(); guest_state_enter_irqoff(); < run the vcpu > guest_state_exit_irqoff(); < take any pending IRQs > guest_timing_exit_irqoff(); Since instrumentation may make use of RCU, we must also ensure that no instrumented code is run during the EQS. I've split out the critical section into a new kvm_arm_enter_exit_vcpu() helper which is marked noinstr. Fixes: 1b3d546daf85ed2b ("arm/arm64: KVM: Properly account for guest CPU time") Reported-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> Cc: Alexandru Elisei <alexandru.elisei@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will@kernel.org> Message-Id: <20220201132926.3301912-3-mark.rutland@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-28Merge tag 'kvmarm-fixes-5.17-1' of ↵Paolo Bonzini4-15/+28
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 5.17, take #1 - Correctly update the shadow register on exception injection when running in nVHE mode - Correctly use the mm_ops indirection when performing cache invalidation from the page-table walker - Restrict the vgic-v3 workaround for SEIS to the two known broken implementations
2022-01-24KVM: arm64: Use shadow SPSR_EL1 when injecting exceptions on !VHEMarc Zyngier1-1/+4
Injecting an exception into a guest with non-VHE is risky business. Instead of writing in the shadow register for the switch code to restore it, we override the CPU register instead. Which gets overriden a few instructions later by said restore code. The result is that although the guest correctly gets the exception, it will return to the original context in some random state, depending on what was there the first place... Boo. Fix the issue by writing to the shadow register. The original code is absolutely fine on VHE, as the state is already loaded, and writing to the shadow register in that case would actually be a bug. Fixes: bb666c472ca2 ("KVM: arm64: Inject AArch64 exceptions from HYP") Cc: stable@vger.kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Fuad Tabba <tabba@google.com> Link: https://lore.kernel.org/r/20220121184207.423426-1-maz@kernel.org
2022-01-22KVM: arm64: vgic-v3: Restrict SEIS workaround to known broken systemsMarc Zyngier2-2/+18
Contrary to what df652bcf1136 ("KVM: arm64: vgic-v3: Work around GICv3 locally generated SErrors") was asserting, there is at least one other system out there (Cavium ThunderX2) implementing SEIS, and not in an obviously broken way. So instead of imposing the M1 workaround on an innocent bystander, let's limit it to the two known broken Apple implementations. Fixes: df652bcf1136 ("KVM: arm64: vgic-v3: Work around GICv3 locally generated SErrors") Reported-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20220122103912.795026-1-maz@kernel.org
2022-01-14KVM: arm64: pkvm: Use the mm_ops indirection for cache maintenanceMarc Zyngier1-12/+6
CMOs issued from EL2 cannot directly use the kernel helpers, as EL2 doesn't have a mapping of the guest pages. Oops. Instead, use the mm_ops indirection to use helpers that will perform a mapping at EL2 and allow the CMO to be effective. Fixes: 25aa28691bb9 ("KVM: arm64: Move guest CMOs to the fault handlers") Reviewed-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220114125038.1336965-1-maz@kernel.org
2022-01-07Merge tag 'kvmarm-5.17' of ↵Paolo Bonzini30-304/+849
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for Linux 5.16 - Simplification of the 'vcpu first run' by integrating it into KVM's 'pid change' flow - Refactoring of the FP and SVE state tracking, also leading to a simpler state and less shared data between EL1 and EL2 in the nVHE case - Tidy up the header file usage for the nvhe hyp object - New HYP unsharing mechanism, finally allowing pages to be unmapped from the Stage-1 EL2 page-tables - Various pKVM cleanups around refcounting and sharing - A couple of vgic fixes for bugs that would trigger once the vcpu xarray rework is merged, but not sooner - Add minimal support for ARMv8.7's PMU extension - Rework kvm_pgtable initialisation ahead of the NV work - New selftest for IRQ injection - Teach selftests about the lack of default IPA space and page sizes - Expand sysreg selftest to deal with Pointer Authentication - The usual bunch of cleanups and doc update
2022-01-04Merge branch kvm-arm64/misc-5.17 into kvmarm-master/nextMarc Zyngier5-13/+12
* kvm-arm64/misc-5.17: : . : Misc fixes and improvements: : - Add minimal support for ARMv8.7's PMU extension : - Constify kvm_io_gic_ops : - Drop kvm_is_transparent_hugepage() prototype : - Drop unused workaround_flags field : - Rework kvm_pgtable initialisation : - Documentation fixes : - Replace open-coded SCTLR_EL1.EE useage with its defined macro : - Sysreg list selftest update to handle PAuth : - Include cleanups : . KVM: arm64: vgic: Replace kernel.h with the necessary inclusions KVM: arm64: Fix comment typo in kvm_vcpu_finalize_sve() KVM: arm64: selftests: get-reg-list: Add pauth configuration KVM: arm64: Fix comment on barrier in kvm_psci_vcpu_on() KVM: arm64: Fix comment for kvm_reset_vcpu() KVM: arm64: Use defined value for SCTLR_ELx_EE KVM: arm64: Rework kvm_pgtable initialisation KVM: arm64: Drop unused workaround_flags vcpu field Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-01-04KVM: arm64: Fix comment typo in kvm_vcpu_finalize_sve()Zenghui Yu1-1/+1
kvm_arm_init_arch_resources() was renamed to kvm_arm_init_sve() in commit a3be836df7cb ("KVM: arm/arm64: Demote kvm_arm_init_arch_resources() to just set up SVE"). Fix the function name in comment of kvm_vcpu_finalize_sve(). Signed-off-by: Zenghui Yu <yuzenghui@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211230141535.1389-1-yuzenghui@huawei.com
2021-12-20KVM: arm64: Fix comment on barrier in kvm_psci_vcpu_on()Fuad Tabba1-1/+1
The barrier is there for power_off rather than power_state. Probably typo in commit 358b28f09f0ab074 ("arm/arm64: KVM: Allow a VCPU to fully reset itself"). Signed-off-by: Fuad Tabba <tabba@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211208193257.667613-3-tabba@google.com
2021-12-20KVM: arm64: Fix comment for kvm_reset_vcpu()Fuad Tabba1-4/+3
The comment for kvm_reset_vcpu() refers to the sysreg table as being the table above, probably because of the code extracted at commit f4672752c321ea36 ("arm64: KVM: virtual CPU reset"). Fix the comment to remove the potentially confusing reference. Signed-off-by: Fuad Tabba <tabba@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211208193257.667613-2-tabba@google.com
2021-12-16KVM: arm64: Rework kvm_pgtable initialisationMarc Zyngier3-7/+7
Ganapatrao reported that the kvm_pgtable->mmu pointer is more or less hardcoded to the main S2 mmu structure, while the nested code needs it to point to other instances (as we have one instance per nested context). Rework the initialisation of the kvm_pgtable structure so that this assumtion doesn't hold true anymore. This requires some minor changes to the order in which things are initialised (the mmu->arch pointer being the critical one). Reported-by: Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com> Reviewed-by: Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211129200150.351436-5-maz@kernel.org
2021-12-16Merge branch kvm-arm64/pkvm-hyp-sharing into kvmarm-master/nextMarc Zyngier10-119/+713
* kvm-arm64/pkvm-hyp-sharing: : . : Series from Quentin Perret, implementing HYP page share/unshare: : : This series implements an unshare hypercall at EL2 in nVHE : protected mode, and makes use of it to unmmap guest-specific : data-structures from EL2 stage-1 during guest tear-down. : Crucially, the implementation of the share and unshare : routines use page refcounts in the host kernel to avoid : accidentally unmapping data-structures that overlap a common : page. : [...] : . KVM: arm64: pkvm: Unshare guest structs during teardown KVM: arm64: Expose unshare hypercall to the host KVM: arm64: Implement do_unshare() helper for unsharing memory KVM: arm64: Implement __pkvm_host_share_hyp() using do_share() KVM: arm64: Implement do_share() helper for sharing memory KVM: arm64: Introduce wrappers for host and hyp spin lock accessors KVM: arm64: Extend pkvm_page_state enumeration to handle absent pages KVM: arm64: pkvm: Refcount the pages shared with EL2 KVM: arm64: Introduce kvm_share_hyp() KVM: arm64: Implement kvm_pgtable_hyp_unmap() at EL2 KVM: arm64: Hook up ->page_count() for hypervisor stage-1 page-table KVM: arm64: Fixup hyp stage-1 refcount KVM: arm64: Refcount hyp stage-1 pgtable pages KVM: arm64: Provide {get,put}_page() stubs for early hyp allocator Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-12-16KVM: arm64: pkvm: Unshare guest structs during teardownQuentin Perret4-4/+82
Make use of the newly introduced unshare hypercall during guest teardown to unmap guest-related data structures from the hyp stage-1. Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211215161232.1480836-15-qperret@google.com
2021-12-16KVM: arm64: Expose unshare hypercall to the hostWill Deacon3-0/+42
Introduce an unshare hypercall which can be used to unmap memory from the hypervisor stage-1 in nVHE protected mode. This will be useful to update the EL2 ownership state of pages during guest teardown, and avoids keeping dangling mappings to unreferenced portions of memory. Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211215161232.1480836-14-qperret@google.com
2021-12-16KVM: arm64: Implement do_unshare() helper for unsharing memoryWill Deacon1-0/+115
Tearing down a previously shared memory region results in the borrower losing access to the underlying pages and returning them to the "owned" state in the owner. Implement a do_unshare() helper, along the same lines as do_share(), to provide this functionality for the host-to-hyp case. Reviewed-by: Andrew Walbran <qwandor@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211215161232.1480836-13-qperret@google.com
2021-12-16KVM: arm64: Implement __pkvm_host_share_hyp() using do_share()Will Deacon1-88/+33
__pkvm_host_share_hyp() shares memory between the host and the hypervisor so implement it as an invocation of the new do_share() mechanism. Note that double-sharing is no longer permitted (as this allows us to reduce the number of page-table walks significantly), but is thankfully no longer relied upon by the host. Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211215161232.1480836-12-qperret@google.com
2021-12-16KVM: arm64: Implement do_share() helper for sharing memoryWill Deacon1-0/+237
By default, protected KVM isolates memory pages so that they are accessible only to their owner: be it the host kernel, the hypervisor at EL2 or (in future) the guest. Establishing shared-memory regions between these components therefore involves a transition for each page so that the owner can share memory with a borrower under a certain set of permissions. Introduce a do_share() helper for safely sharing a memory region between two components. Currently, only host-to-hyp sharing is implemented, but the code is easily extended to handle other combinations and the permission checks for each component are reusable. Reviewed-by: Andrew Walbran <qwandor@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211215161232.1480836-11-qperret@google.com
2021-12-16KVM: arm64: Introduce wrappers for host and hyp spin lock accessorsWill Deacon1-6/+26
In preparation for adding additional locked sections for manipulating page-tables at EL2, introduce some simple wrappers around the host and hypervisor locks so that it's a bit easier to read and bit more difficult to take the wrong lock (or even take them in the wrong order). Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211215161232.1480836-10-qperret@google.com
2021-12-16KVM: arm64: Extend pkvm_page_state enumeration to handle absent pagesWill Deacon1-0/+5
Explicitly name the combination of SW0 | SW1 as reserved in the pte and introduce a new PKVM_NOPAGE meta-state which, although not directly stored in the software bits of the pte, can be used to represent an entry for which there is no underlying page. This is distinct from an invalid pte, as stage-2 identity mappings for the host are created lazily and so an invalid pte there is the same as a valid mapping for the purposes of ownership information. This state will be used for permission checking during page transitions in later patches. Reviewed-by: Andrew Walbran <qwandor@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211215161232.1480836-9-qperret@google.com
2021-12-16KVM: arm64: pkvm: Refcount the pages shared with EL2Quentin Perret1-10/+68
In order to simplify the page tracking infrastructure at EL2 in nVHE protected mode, move the responsibility of refcounting pages that are shared multiple times on the host. In order to do so, let's create a red-black tree tracking all the PFNs that have been shared, along with a refcount. Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211215161232.1480836-8-qperret@google.com
2021-12-16KVM: arm64: Introduce kvm_share_hyp()Quentin Perret4-10/+25
The create_hyp_mappings() function can currently be called at any point in time. However, its behaviour in protected mode changes widely depending on when it is being called. Prior to KVM init, it is used to create the temporary page-table used to bring-up the hypervisor, and later on it is transparently turned into a 'share' hypercall when the kernel has lost control over the hypervisor stage-1. In order to prepare the ground for also unsharing pages with the hypervisor during guest teardown, introduce a kvm_share_hyp() function to make it clear in which places a share hypercall should be expected, as we will soon need a matching unshare hypercall in all those places. Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211215161232.1480836-7-qperret@google.com
2021-12-16KVM: arm64: Implement kvm_pgtable_hyp_unmap() at EL2Will Deacon1-0/+63
Implement kvm_pgtable_hyp_unmap() which can be used to remove hypervisor stage-1 mappings at EL2. Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211215161232.1480836-6-qperret@google.com
2021-12-16KVM: arm64: Hook up ->page_count() for hypervisor stage-1 page-tableWill Deacon1-0/+1
kvm_pgtable_hyp_unmap() relies on the ->page_count() function callback being provided by the memory-management operations for the page-table. Wire up this callback for the hypervisor stage-1 page-table. Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211215161232.1480836-5-qperret@google.com
2021-12-16KVM: arm64: Fixup hyp stage-1 refcountQuentin Perret1-5/+16
In nVHE-protected mode, the hyp stage-1 page-table refcount is broken due to the lack of refcount support in the early allocator. Fix-up the refcount in the finalize walker, once the 'hyp_vmemmap' is up and running. Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211215161232.1480836-4-qperret@google.com
2021-12-16KVM: arm64: Refcount hyp stage-1 pgtable pagesQuentin Perret1-20/+19
To prepare the ground for allowing hyp stage-1 mappings to be removed at run-time, update the KVM page-table code to maintain a correct refcount using the ->{get,put}_page() function callbacks. Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211215161232.1480836-3-qperret@google.com
2021-12-16KVM: arm64: Provide {get,put}_page() stubs for early hyp allocatorQuentin Perret1-0/+5
In nVHE protected mode, the EL2 code uses a temporary allocator during boot while re-creating its stage-1 page-table. Unfortunately, the hyp_vmmemap is not ready to use at this stage, so refcounting pages is not possible. That is not currently a problem because hyp stage-1 mappings are never removed, which implies refcounting of page-table pages is unnecessary. In preparation for allowing hypervisor stage-1 mappings to be removed, provide stub implementations for {get,put}_page() in the early allocator. Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211215161232.1480836-2-qperret@google.com
2021-12-16Merge branch kvm-arm64/vgic-fixes-5.17 into kvmarm-master/nextMarc Zyngier3-7/+9
* kvm-arm64/vgic-fixes-5.17: : . : A few vgic fixes: : - Harden vgic-v3 error handling paths against signed vs unsigned : comparison that will happen once the xarray-based vcpus are in : - Demote userspace-triggered console output to kvm_debug() : . KVM: arm64: vgic: Demote userspace-triggered console prints to kvm_debug() KVM: arm64: vgic-v3: Fix vcpu index comparison Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-12-16KVM: arm64: vgic: Demote userspace-triggered console prints to kvm_debug()Marc Zyngier2-4/+4
Running the KVM selftests results in these messages being dumped in the kernel console: [ 188.051073] kvm [469]: VGIC redist and dist frames overlap [ 188.056820] kvm [469]: VGIC redist and dist frames overlap [ 188.076199] kvm [469]: VGIC redist and dist frames overlap Being amle to trigger this from userspace is definitely not on, so demote these warnings to kvm_debug(). Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211216104507.1482017-1-maz@kernel.org
2021-12-16KVM: arm64: vgic-v3: Fix vcpu index comparisonMarc Zyngier1-3/+5
When handling an error at the point where we try and register all the redistributors, we unregister all the previously registered frames by counting down from the failing index. However, the way the code is written relies on that index being a signed value. Which won't be true once we switch to an xarray-based vcpu set. Since this code is pretty awkward the first place, and that the failure mode is hard to spot, rewrite this loop to iterate over the vcpus upwards rather than downwards. Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211216104526.1482124-1-maz@kernel.org
2021-12-15Merge branch kvm-arm64/pkvm-cleanups-5.17 into kvmarm-master/nextMarc Zyngier7-6/+19
* kvm-arm64/pkvm-cleanups-5.17: : . : pKVM cleanups from Quentin Perret: : : This series is a collection of various fixes and cleanups for KVM/arm64 : when running in nVHE protected mode. The first two patches are real : fixes/improvements, the following two are minor cleanups, and the last : two help satisfy my paranoia so they're certainly optional. : . KVM: arm64: pkvm: Make kvm_host_owns_hyp_mappings() robust to VHE KVM: arm64: pkvm: Stub io map functions KVM: arm64: Make __io_map_base static KVM: arm64: Make the hyp memory pool static KVM: arm64: pkvm: Disable GICv2 support KVM: arm64: pkvm: Fix hyp_pool max order Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-12-15KVM: arm64: pkvm: Make kvm_host_owns_hyp_mappings() robust to VHEQuentin Perret1-0/+3
The kvm_host_owns_hyp_mappings() function should return true if and only if the host kernel is responsible for creating the hypervisor stage-1 mappings. That is only possible in standard non-VHE mode, or during boot in protected nVHE mode. But either way, none of this makes sense in VHE, so make sure to catch this case as well, hence making the function return sensible values in any context (VHE or not). Suggested-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211208152300.2478542-7-qperret@google.com
2021-12-15KVM: arm64: pkvm: Stub io map functionsQuentin Perret1-0/+6
Now that GICv2 is disabled in nVHE protected mode there should be no other reason for the host to use create_hyp_io_mappings() or kvm_phys_addr_ioremap(). Add sanity checks to make sure that assumption remains true looking forward. Signed-off-by: Quentin Perret <qperret@google.com> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211208152300.2478542-6-qperret@google.com
2021-12-15KVM: arm64: Make __io_map_base staticQuentin Perret2-2/+2
The __io_map_base variable is used at EL2 to track the end of the hypervisor's "private" VA range in nVHE protected mode. However it doesn't need to be used outside of mm.c, so let's make it static to keep all the hyp VA allocation logic in one place. Signed-off-by: Quentin Perret <qperret@google.com> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211208152300.2478542-5-qperret@google.com
2021-12-15KVM: arm64: Make the hyp memory pool staticQuentin Perret2-2/+1
The hyp memory pool struct is sized to fit exactly the needs of the hypervisor stage-1 page-table allocator, so it is important it is not used for anything else. As it is currently used only from setup.c, reduce its visibility by marking it static. Signed-off-by: Quentin Perret <qperret@google.com> Reviewed-by: Andrew Walbran <qwandor@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211208152300.2478542-4-qperret@google.com
2021-12-15KVM: arm64: pkvm: Disable GICv2 supportQuentin Perret2-1/+6
GICv2 requires having device mappings in guests and the hypervisor, which is incompatible with the current pKVM EL2 page ownership model which only covers memory. While it would be desirable to support pKVM with GICv2, this will require a lot more work, so let's make the current assumption clear until then. Co-developed-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Quentin Perret <qperret@google.com> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20211208152300.2478542-3-qperret@google.com
2021-12-15KVM: arm64: pkvm: Fix hyp_pool max orderQuentin Perret1-1/+1
The EL2 page allocator in protected mode maintains a per-pool max order value to optimize allocations when the memory region it covers is small. However, the max order value is currently under-estimated whenever the number of pages in the region is a power of two. Fix the estimation. Signed-off-by: Quentin Perret <qperret@google.com> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211208152300.2478542-2-qperret@google.com
2021-12-09KVM: arm64: Use Makefile.kvm for common filesDavid Woodhouse1-4/+2
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Marc Zyngier <maz@kernel.org> Message-Id: <20211121125451.9489-8-dwmw2@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-08KVM: Add helpers to wake/query blocking vCPUSean Christopherson2-3/+2
Add helpers to wake and query a blocking vCPU. In addition to providing nice names, the helpers reduce the probability of KVM neglecting to use kvm_arch_vcpu_get_wait(). No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211009021236.4122790-20-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-08KVM: Rename kvm_vcpu_block() => kvm_vcpu_halt()Sean Christopherson4-4/+4
Rename kvm_vcpu_block() to kvm_vcpu_halt() in preparation for splitting the actual "block" sequences into a separate helper (to be named kvm_vcpu_block()). x86 will use the standalone block-only path to handle non-halt cases where the vCPU is not runnable. Rename block_ns to halt_ns to match the new function name. No functional change intended. Reviewed-by: David Matlack <dmatlack@google.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211009021236.4122790-14-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-08KVM: arm64: Move vGIC v4 handling for WFI out arch callback hookSean Christopherson2-19/+36
Move the put and reload of the vGIC out of the block/unblock callbacks and into a dedicated WFI helper. Functionally, this is nearly a nop as the block hook is called at the very beginning of kvm_vcpu_block(), and the only code in kvm_vcpu_block() after the unblock hook is to update the halt-polling controls, i.e. can only affect the next WFI. Back when the arch (un)blocking hooks were added by commits 3217f7c25bca ("KVM: Add kvm_arch_vcpu_{un}blocking callbacks) and d35268da6687 ("arm/arm64: KVM: arch_timer: Only schedule soft timer on vcpu_block"), the hooks were invoked only when KVM was about to "block", i.e. schedule out the vCPU. The use case at the time was to schedule a timer in the host based on the earliest timer in the guest in order to wake the blocking vCPU when the emulated guest timer fired. Commit accb99bcd0ca ("KVM: arm/arm64: Simplify bg_timer programming") reworked the timer logic to be even more precise, by waiting until the vCPU was actually scheduled out, and so move the timer logic from the (un)blocking hooks to vcpu_load/put. In the meantime, the hooks gained usage for enabling vGIC v4 doorbells in commit df9ba95993b9 ("KVM: arm/arm64: GICv4: Use the doorbell interrupt as an unblocking source"), and added related logic for the VMCR in commit 5eeaf10eec39 ("KVM: arm/arm64: Sync ICH_VMCR_EL2 back when about to block"). Finally, commit 07ab0f8d9a12 ("KVM: Call kvm_arch_vcpu_blocking early into the blocking sequence") hoisted the (un)blocking hooks so that they wrapped KVM's halt-polling logic in addition to the core "block" logic. In other words, the original need for arch hooks to take action _only_ in the block path is long since gone. Cc: Oliver Upton <oupton@google.com> Cc: Marc Zyngier <maz@kernel.org> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211009021236.4122790-11-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-08KVM: Keep memslots in tree-based structures instead of array-based onesMaciej S. Szmigiero1-4/+4
The current memslot code uses a (reverse gfn-ordered) memslot array for keeping track of them. Because the memslot array that is currently in use cannot be modified every memslot management operation (create, delete, move, change flags) has to make a copy of the whole array so it has a scratch copy to work on. Strictly speaking, however, it is only necessary to make copy of the memslot that is being modified, copying all the memslots currently present is just a limitation of the array-based memslot implementation. Two memslot sets, however, are still needed so the VM continues to run on the currently active set while the requested operation is being performed on the second, currently inactive one. In order to have two memslot sets, but only one copy of actual memslots it is necessary to split out the memslot data from the memslot sets. The memslots themselves should be also kept independent of each other so they can be individually added or deleted. These two memslot sets should normally point to the same set of memslots. They can, however, be desynchronized when performing a memslot management operation by replacing the memslot to be modified by its copy. After the operation is complete, both memslot sets once again point to the same, common set of memslot data. This commit implements the aforementioned idea. For tracking of gfns an ordinary rbtree is used since memslots cannot overlap in the guest address space and so this data structure is sufficient for ensuring that lookups are done quickly. The "last used slot" mini-caches (both per-slot set one and per-vCPU one), that keep track of the last found-by-gfn memslot, are still present in the new code. Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Message-Id: <17c0cf3663b760a0d3753d4ac08c0753e941b811.1638817641.git.maciej.szmigiero@oracle.com>
2021-12-08KVM: Use interval tree to do fast hva lookup in memslotsMaciej S. Szmigiero1-0/+1
The current memslots implementation only allows quick binary search by gfn, quick lookup by hva is not possible - the implementation has to do a linear scan of the whole memslots array, even though the operation being performed might apply just to a single memslot. This significantly hurts performance of per-hva operations with higher memslot counts. Since hva ranges can overlap between memslots an interval tree is needed for tracking them. [sean: handle interval tree updates in kvm_replace_memslot()] Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Message-Id: <d66b9974becaa9839be9c4e1a5de97b177b4ac20.1638817640.git.maciej.szmigiero@oracle.com>
2021-12-08KVM: Stop passing kvm_userspace_memory_region to arch memslot hooksSean Christopherson1-2/+0
Drop the @mem param from kvm_arch_{prepare,commit}_memory_region() now that its use has been removed in all architectures. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Message-Id: <aa5ed3e62c27e881d0d8bc0acbc1572bc336dc19.1638817640.git.maciej.szmigiero@oracle.com>
2021-12-08KVM: arm64: Use "new" memslot instead of userspace memory regionSean Christopherson1-4/+6
Get the slot ID, hva, etc... from the "new" memslot instead of the userspace memory region when preparing/committing a memory region. This will allow a future commit to drop @mem from the prepare/commit hooks once all architectures convert to using "new". Opportunistically wait to get the hva begin+end until after filtering out the DELETE case in anticipation of a future commit passing NULL for @new when deleting a memslot. Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Message-Id: <c019d00c2531520c52e0b52dfda1be5aa898103c.1638817639.git.maciej.szmigiero@oracle.com>
2021-12-08KVM: Let/force architectures to deal with arch specific memslot dataSean Christopherson1-3/+4
Pass the "old" slot to kvm_arch_prepare_memory_region() and force arch code to handle propagating arch specific data from "new" to "old" when necessary. This is a baby step towards dynamically allocating "new" from the get go, and is a (very) minor performance boost on x86 due to not unnecessarily copying arch data. For PPC HV, copy the rmap in the !CREATE and !DELETE paths, i.e. for MOVE and FLAGS_ONLY. This is functionally a nop as the previous behavior would overwrite the pointer for CREATE, and eventually discard/ignore it for DELETE. For x86, copy the arch data only for FLAGS_ONLY changes. Unlike PPC HV, x86 needs to reallocate arch data in the MOVE case as the size of x86's allocations depend on the alignment of the memslot's gfn. Opportunistically tweak kvm_arch_prepare_memory_region()'s param order to match the "commit" prototype. Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> [mss: add missing RISCV kvm_arch_prepare_memory_region() change] Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com> Message-Id: <67dea5f11bbcfd71e3da5986f11e87f5dd4013f9.1638817639.git.maciej.szmigiero@oracle.com>
2021-12-08KVM: Use 'unsigned long' as kvm_for_each_vcpu()'s indexMarc Zyngier12-27/+30
Everywhere we use kvm_for_each_vpcu(), we use an int as the vcpu index. Unfortunately, we're about to move rework the iterator, which requires this to be upgrade to an unsigned long. Let's bite the bullet and repaint all of it in one go. Signed-off-by: Marc Zyngier <maz@kernel.org> Message-Id: <20211116160403.4074052-7-maz@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-08KVM: Move wiping of the kvm->vcpus array to common codeMarc Zyngier1-9/+1
All architectures have similar loops iterating over the vcpus, freeing one vcpu at a time, and eventually wiping the reference off the vcpus array. They are also inconsistently taking the kvm->lock mutex when wiping the references from the array. Make this code common, which will simplify further changes. The locking is dropped altogether, as this should only be called when there is no further references on the kvm structure. Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Message-Id: <20211116160403.4074052-2-maz@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-07Merge branch kvm-arm64/misc-5.17 into kvmarm-master/nextMarc Zyngier3-2/+3
* kvm-arm64/misc-5.17: : . : - Add minimal support for ARMv8.7's PMU extension : - Constify kvm_io_gic_ops : - Drop kvm_is_transparent_hugepage() prototype : . KVM: Drop stale kvm_is_transparent_hugepage() declaration KVM: arm64: Constify kvm_io_gic_ops KVM: arm64: Add minimal handling for the ARMv8.7 PMU Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-12-07Merge branch kvm-arm64/hyp-header-split into kvmarm-master/nextMarc Zyngier9-63/+37
* kvm-arm64/hyp-header-split: : . : Tidy up the header file usage for the nvhe hyp object so : that header files under arch/arm64/kvm/hyp/include are not : included by host code running at EL1. : . KVM: arm64: Move host EL1 code out of hyp/ directory KVM: arm64: Generate hyp_constants.h for the host arm64: Add missing include of asm/cpufeature.h to asm/mmu.h Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-12-06KVM: arm64: Move host EL1 code out of hyp/ directoryWill Deacon7-63/+9
kvm/hyp/reserved_mem.c contains host code executing at EL1 and is not linked into the hypervisor object. Move the file into kvm/pkvm.c and rework the headers so that the definitions shared between the host and the hypervisor live in asm/kvm_pkvm.h. Signed-off-by: Will Deacon <will@kernel.org> 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/20211202171048.26924-4-will@kernel.org