Atish Patra 69637dde69 hypervisor: aarch64: capture the guest counter for snapshot/restore ...

Unlike x86, ARM64 has no kvmclock support to sync guest time upon
required. However, the guest reads the architected virtual timer
(CNTVCT_EL0) directly which can be modified by the VMM to update the
time after snapshot restore. Since the CNTVCT is in ticks, we also need
to read CNTFRQ (via mrs due to lack of ONEREG interface) to compute the
ticks from wall clock difference.

Because the counter is a vCPU register, the capture must run with the
vCPUs quiesced, so the VMM now captures the clock just after
cpu_manager.pause() through the boot vCPU. This is behaviorally
identical for x86, whose clock is VM-wide. There is no restore/advance
yet, so aarch64 guests still resume behind real time until the following
commit.

Signed-off-by: Atish Patra <atishp@meta.com>

2026-06-18 22:59:37 +00:00

..

src

hypervisor: aarch64: capture the guest counter for snapshot/restore

2026-06-18 22:59:37 +00:00

build.rs

build: Add "fuzzing" as a valid cfg(..) attribute

2024-05-08 08:10:28 +00:00

Cargo.toml

vmm: Make sev_snp depend on igvm

2026-06-10 21:29:40 +00:00