On Wed, Feb 19, 2025 at 3:01 AM Paolo Bonzini <pbonz...@redhat.com> wrote:
>
> There is nothing that overwrites env->misa_mxl, so it is a constant. Do
The idea is that misa_mxl can change, although that's not supported now.
> not let a corrupted migration stream change the value; changing misa_mxl
Does this actually happen? If the migration data is corrupted won't we
have all sorts of strange issues?
Alistair
> would have a snowball effect on, for example, the valid VM modes.
>
> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
> ---
> target/riscv/machine.c | 13 +++++++++++++
> 1 file changed, 13 insertions(+)
>
> diff --git a/target/riscv/machine.c b/target/riscv/machine.c
> index d8445244ab2..c3d8e7c4005 100644
> --- a/target/riscv/machine.c
> +++ b/target/riscv/machine.c
> @@ -375,6 +375,18 @@ static const VMStateDescription vmstate_ssp = {
> }
> };
>
> +static bool riscv_validate_misa_mxl(void *opaque, int version_id)
> +{
> + RISCVCPU *cpu = RISCV_CPU(opaque);
> + CPURISCVState *env = &cpu->env;
> + RISCVCPUClass *mcc = RISCV_CPU_GET_CLASS(cpu);
> + uint32_t misa_mxl_saved = env->misa_mxl;
> +
> + /* Preserve misa_mxl even if the migration stream corrupted it */
> + env->misa_mxl = mcc->misa_mxl_max;
> + return misa_mxl_saved == mcc->misa_mxl_max;
> +}
> +
> const VMStateDescription vmstate_riscv_cpu = {
> .name = "cpu",
> .version_id = 10,
> @@ -394,6 +406,7 @@ const VMStateDescription vmstate_riscv_cpu = {
> VMSTATE_UINTTL(env.priv_ver, RISCVCPU),
> VMSTATE_UINTTL(env.vext_ver, RISCVCPU),
> VMSTATE_UINT32(env.misa_mxl, RISCVCPU),
> + VMSTATE_VALIDATE("MXL must match", riscv_validate_misa_mxl),
> VMSTATE_UINT32(env.misa_ext, RISCVCPU),
> VMSTATE_UNUSED(4),
> VMSTATE_UINT32(env.misa_ext_mask, RISCVCPU),
> --
> 2.48.1
>
>
