kernel.git/arch/arm64/kvm/hypercalls.c, branch master

arm64: kvm, smccc: Introduce and use API for getting hypervisor UUID

2025-05-23T16:30:55Z

The KVM/arm64 uses SMCCC to detect hypervisor presence. That code is private, and it follows the SMCCC specification. Other existing and emerging hypervisor guest implementations can and should use that standard approach as well. Factor out a common infrastructure that the guests can use, update KVM to employ the new API. The central notion of the SMCCC method is the UUID of the hypervisor, and the new API follows that. No functional changes. Validated with a KVM/arm64 guest. Signed-off-by: Roman Kisel Acked-by: Arnd Bergmann Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/20250428210742.435282-2-romank@linux.microsoft.com Signed-off-by: Wei Liu Message-ID: <20250428210742.435282-2-romank@linux.microsoft.com>

KVM: arm64: Introduce KVM_REG_ARM_VENDOR_HYP_BMAP_2

2025-02-26T21:30:36Z

The vendor_hyp_bmap bitmap holds the information about the Vendor Hyp services available to the user space and can be get/set using {G, S}ET_ONE_REG interfaces. This is done using the pseudo-firmware bitmap register KVM_REG_ARM_VENDOR_HYP_BMAP. At present, this bitmap is a 64 bit one and since the function numbers for newly added DISCOVER_IPML_* hypercalls are 64-65, introduce another pseudo-firmware bitmap register KVM_REG_ARM_VENDOR_HYP_BMAP_2. Reviewed-by: Sebastian Ott Signed-off-by: Shameer Kolothum Link: https://lore.kernel.org/r/20250221140229.12588-4-shameerali.kolothum.thodi@huawei.com Signed-off-by: Oliver Upton

Merge branch kvm-arm64/psci-1.3 into kvmarm/next

2024-11-11T18:36:46Z

* kvm-arm64/psci-1.3: : PSCI v1.3 support, courtesy of David Woodhouse : : Bump KVM's PSCI implementation up to v1.3, with the added bonus of : implementing the SYSTEM_OFF2 call. Like other system-scoped PSCI calls, : this gets relayed to userspace for further processing with a new : KVM_SYSTEM_EVENT_SHUTDOWN flag. : : As an added bonus, implement client-side support for hibernation with : the SYSTEM_OFF2 call. arm64: Use SYSTEM_OFF2 PSCI call to power off for hibernate KVM: arm64: nvhe: Pass through PSCI v1.3 SYSTEM_OFF2 call KVM: selftests: Add test for PSCI SYSTEM_OFF2 KVM: arm64: Add support for PSCI v1.2 and v1.3 KVM: arm64: Add PSCI v1.3 SYSTEM_OFF2 function for hibernation firmware/psci: Add definitions for PSCI v1.3 specification Signed-off-by: Oliver Upton

KVM: arm64: Add support for PSCI v1.2 and v1.3

2024-10-24T23:38:07Z

As with PSCI v1.1 in commit 512865d83fd9 ("KVM: arm64: Bump guest PSCI version to 1.1"), expose v1.3 to the guest by default. The SYSTEM_OFF2 call which is exposed by doing so is compatible for userspace because it's just a new flag in the event that KVM raises, in precisely the same way that SYSTEM_RESET2 was compatible when v1.1 was enabled by default. Signed-off-by: David Woodhouse Reviewed-by: Miguel Luis Link: https://lore.kernel.org/r/20241019172459.2241939-4-dwmw2@infradead.org Signed-off-by: Oliver Upton

KVM: arm64: Use kvm_has_feat() to check if FEAT_SSBS is advertised to the guest

2024-08-25T16:48:44Z

Currently KVM use cpus_have_final_cap() to check if FEAT_SSBS is advertised to the guest. But if FEAT_SSBS is writable and isn't advertised to the guest, this is wrong. Update it to use kvm_has_feat() to check if FEAT_SSBS is advertised to the guest, thus the KVM can do the right thing if FEAT_SSBS isn't advertised to the guest. Signed-off-by: Shaoqin Huang Link: https://lore.kernel.org/r/20240723072004.1470688-3-shahuang@redhat.com Signed-off-by: Marc Zyngier

Merge branch kvm-arm64/smccc-filter-cleanups into kvmarm/next

2023-10-30T20:18:37Z

* kvm-arm64/smccc-filter-cleanups: : Cleanup the management of KVM's SMCCC maple tree : : Avoid the cost of maintaining the SMCCC filter maple tree if userspace : hasn't writen a rule to the filter. While at it, rip out the now : unnecessary VM flag to indicate whether or not the SMCCC filter was : configured. KVM: arm64: Use mtree_empty() to determine if SMCCC filter configured KVM: arm64: Only insert reserved ranges when SMCCC filter is used KVM: arm64: Add a predicate for testing if SMCCC filter is configured Signed-off-by: Oliver Upton

KVM: arm64: Use mtree_empty() to determine if SMCCC filter configured

2023-10-05T09:33:15Z

The smccc_filter maple tree is only populated if userspace attempted to configure it. Use the state of the maple tree to determine if the filter has been configured, eliminating the VM flag. Reviewed-by: Marc Zyngier Link: https://lore.kernel.org/r/20231004234947.207507-4-oliver.upton@linux.dev Signed-off-by: Oliver Upton

KVM: arm64: Only insert reserved ranges when SMCCC filter is used

2023-10-05T09:33:15Z

The reserved ranges are only useful for preventing userspace from adding a rule that intersects with functions we must handle in KVM. If userspace never writes to the SMCCC filter than this is all just wasted work/memory. Insert reserved ranges on the first call to KVM_ARM_VM_SMCCC_FILTER. Reviewed-by: Marc Zyngier Link: https://lore.kernel.org/r/20231004234947.207507-3-oliver.upton@linux.dev Signed-off-by: Oliver Upton

KVM: arm64: Add a predicate for testing if SMCCC filter is configured

2023-10-05T09:33:15Z

Eventually we can drop the VM flag, move around the existing implementation for now. Reviewed-by: Marc Zyngier Link: https://lore.kernel.org/r/20231004234947.207507-2-oliver.upton@linux.dev Signed-off-by: Oliver Upton

KVM: arm64: Get rid of vCPU-scoped feature bitmap

2023-09-21T18:13:29Z

The vCPU-scoped feature bitmap was left in place a couple of releases ago in case the change to VM-scoped vCPU features broke anyone. Nobody has complained and the interop between VM and vCPU bitmaps is pretty gross. Throw it out. Link: https://lore.kernel.org/r/20230920195036.1169791-9-oliver.upton@linux.dev Signed-off-by: Oliver Upton