kernel/linux.git/arch/arm64/include/asm/kvm_hyp.h, branch linux-7.0.y

KVM: arm64: GICv3: nv: Resync LRs/VMCR/HCR early for better MI emulation

2025-11-24T22:29:14+00:00

The current approach to nested GICv3 support is to not do anything while L2 is running, wait a transition from L2 to L1 to resync LRs, VMCR and HCR, and only then evaluate the state to decide whether to generate a maintenance interrupt. This doesn't provide a good quality of emulation, and it would be far preferable to find out early that we need to perform a switch. Move the LRs/VMCR and HCR resync into vgic_v3_sync_nested(), so that we have most of the state available. As we turning the vgic off at this stage to avoid a screaming host MI, add a new helper vgic_v3_flush_nested() that switches the vgic on again. The MI can then be directly injected as required. Tested-by: Fuad Tabba Signed-off-by: Marc Zyngier Tested-by: Mark Brown Link: https://msgid.link/20251120172540.2267180-35-maz@kernel.org Signed-off-by: Oliver Upton

KVM: arm64: Eagerly save VMCR on exit

2025-11-24T22:29:13+00:00

We currently save/restore the VMCR register in a pretty lazy way (on load/put, consistently with what we do with the APRs). However, we are going to need the group-enable bits that are backed by VMCR on each entry (so that we can avoid injecting interrupts for disabled groups). Move the synchronisation from put to sync, which results in some minor churn in the nVHE hypercalls to simplify things. Tested-by: Fuad Tabba Signed-off-by: Marc Zyngier Tested-by: Mark Brown Link: https://msgid.link/20251120172540.2267180-21-maz@kernel.org Signed-off-by: Oliver Upton

KVM: arm64: nv: Nested GICv3 emulation

2025-03-03T22:57:04+00:00

When entering a nested VM, we set up the hypervisor control interface based on what the guest hypervisor has set. Especially, we investigate each list register written by the guest hypervisor whether HW bit is set. If so, we translate hw irq number from the guest's point of view to the real hardware irq number if there is a mapping. Co-developed-by: Jintack Lim Signed-off-by: Jintack Lim [Christoffer: Redesigned execution flow around vcpu load/put] Co-developed-by: Christoffer Dall Signed-off-by: Christoffer Dall [maz: Rewritten to support GICv3 instead of GICv2, NV2 support] Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20250225172930.1850838-9-maz@kernel.org Signed-off-by: Oliver Upton

KVM: arm64: Fix __pkvm_init_switch_pgd call ABI

2024-06-20T17:40:53+00:00

Fix the mismatch between the (incorrect) C signature, C call site, and asm implementation by aligning all three on an API passing the parameters (pgd and SP) separately, instead of as a bundled struct. Remove the now unnecessary memory accesses while the MMU is off from the asm, which simplifies the C caller (as it does not need to convert a VA struct pointer to PA) and makes the code slightly more robust by offsetting the struct fields from C and properly expressing the call to the C compiler (e.g. type checker and kCFI). Fixes: f320bc742bc2 ("KVM: arm64: Prepare the creation of s1 mappings at EL2") Signed-off-by: Pierre-Clément Tosi Acked-by: Will Deacon Link: https://lore.kernel.org/r/20240610063244.2828978-3-ptosi@google.com Signed-off-by: Oliver Upton

KVM: arm64: Allocate memory mapped at hyp for host sve state in pKVM

2024-06-04T14:06:33+00:00

Protected mode needs to maintain (save/restore) the host's sve state, rather than relying on the host kernel to do that. This is to avoid leaking information to the host about guests and the type of operations they are performing. As a first step towards that, allocate memory mapped at hyp, per cpu, for the host sve state. The following patch will use this memory to save/restore the host state. Reviewed-by: Oliver Upton Signed-off-by: Fuad Tabba Link: https://lore.kernel.org/r/20240603122852.3923848-6-tabba@google.com Signed-off-by: Marc Zyngier

KVM: arm64: Fix prototype for __sve_save_state/__sve_restore_state

2024-06-04T14:06:32+00:00

Since the prototypes for __sve_save_state/__sve_restore_state at hyp were added, the underlying macro has acquired a third parameter for saving/restoring ffr. Fix the prototypes to account for the third parameter, and restore the ffr for the guest since it is saved. Suggested-by: Mark Brown Signed-off-by: Fuad Tabba Reviewed-by: Mark Brown Link: https://lore.kernel.org/r/20240603122852.3923848-3-tabba@google.com Signed-off-by: Marc Zyngier

KVM: arm64: Reintroduce __sve_save_state

2024-06-04T14:06:32+00:00

Now that the hypervisor is handling the host sve state in protected mode, it needs to be able to save it. This reverts commit e66425fc9ba3 ("KVM: arm64: Remove unused __sve_save_state"). Reviewed-by: Oliver Upton Signed-off-by: Fuad Tabba Link: https://lore.kernel.org/r/20240603122852.3923848-2-tabba@google.com Signed-off-by: Marc Zyngier

KVM: arm64: Simplify vgic-v3 hypercalls

2024-05-01T15:48:14+00:00

Consolidate the GICv3 VMCR accessor hypercalls into the APR save/restore hypercalls so that all of the EL2 GICv3 state is covered by a single pair of hypercalls. Signed-off-by: Fuad Tabba Acked-by: Oliver Upton Link: https://lore.kernel.org/r/20240423150538.2103045-17-tabba@google.com Signed-off-by: Marc Zyngier

KVM: arm64: Fix typos

2024-02-24T09:13:33+00:00

Fix typos, most reported by "codespell arch/arm64". Only touches comments, no code changes. Signed-off-by: Bjorn Helgaas Cc: James Morse Cc: Suzuki K Poulose Cc: Zenghui Yu Cc: Catalin Marinas Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org Cc: kvmarm@lists.linux.dev Reviewed-by: Zenghui Yu Reviewed-by: Randy Dunlap Link: https://lore.kernel.org/r/20240103231605.1801364-6-helgaas@kernel.org Signed-off-by: Oliver Upton

KVM: arm64: Rename helpers for VHE vCPU load/put

2023-10-20T17:52:01+00:00

The names for the helpers we expose to the 'generic' KVM code are a bit imprecise; we switch the EL0 + EL1 sysreg context and setup trap controls that do not need to change for every guest entry/exit. Rename + shuffle things around a bit in preparation for loading the stage-2 MMU context on vcpu_load(). Link: https://lore.kernel.org/r/20231018233212.2888027-5-oliver.upton@linux.dev Signed-off-by: Oliver Upton