This patch set fixes several timer-related migration issues in QEMU's RISC-V implementation that cause timer events to be lost or behave incorrectly after snapshot save/restore or live migration.
The problems addressed are: 1. ACLINT mtimer time_delta not migrated: The time_delta field in RISCVAclintMTimerState was missing from vmstate, causing incorrect mtime values after snapshot restore. This resulted in guest time appearing "frozen" until enough virtual time elapsed to compensate for the offset error. 2. ACLINT mtimer timers array not migrated: Active timer events scheduled via riscv_aclint_mtimer_write_timecmp() were not being migrated, causing pending timer interrupts to be lost after restore. 3. CPU stimer/vstimer not migrated: The S-mode and VS-mode timer pointers in CPURISCVState were missing from vmstate_riscv_cpu, causing supervisor-level timer events to be lost. The patch set introduces a new VMSTATE_TIMER_PTR_VARRAY macro to handle migration of variable-length timer pointer arrays, and adds the missing timer fields to the appropriate vmstate structures. Signed-off-by: TANG Tiancheng <lyn...@linux.alibaba.com> --- Changes in v3: - Remove 'include/' of the subject at patch v2 2/4. - Added Reviewed-by from Peter Xu. - Link to v2: https://lore.kernel.org/qemu-devel/20250910-timers-v2-0-31359f1f6...@linux.alibaba.com Changes in v2: - Split VMSTATE_VARRAY_OF_POINTER_UINT32() into a separate patch, and define VMSTATE_TIMER_PTR_VARRAY() in riscv_aclint.h. - Added Reviewed-by from Daniel Henrique Barboza. - Link to v1: https://lore.kernel.org/qemu-devel/20250909-timers-v1-0-7ee18a9d8...@linux.alibaba.com --- TANG Tiancheng (4): hw/intc: Save time_delta in RISC-V mtimer VMState migration: Add support for a variable-length array of UINT32 pointers hw/intc: Save timers array in RISC-V mtimer VMState target/riscv: Save stimer and vstimer in CPU vmstate hw/intc/riscv_aclint.c | 7 +++++-- include/hw/intc/riscv_aclint.h | 4 ++++ include/migration/vmstate.h | 10 ++++++++++ target/riscv/machine.c | 25 +++++++++++++++++++++++++ 4 files changed, 44 insertions(+), 2 deletions(-) --- base-commit: 6a9fa5ef3230a7d51e0d953a59ee9ef10af705b8 change-id: 20250909-timers-18c2c67b1a2a Best regards, -- TANG Tiancheng <lyn...@linux.alibaba.com>
