Re: [Qemu-devel] [PATCH v2 5/5] tpm: extend TPM CRB with state migration support

[Stefan Berger <stefanb@linux.vnet.ibm.com>]

On 01/19/2018 09:11 AM, Marc-André Lureau wrote:
> From: Stefan Berger <stefanb@linux.vnet.ibm.com>
>
> We need to synchronize with the backend thread to make sure that a command
> being processed by the external TPM emulator has completed and its
> response been received. In case the bottom half did not run, we run the
> function it is supposed to run.
>
> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
> [ Marc-André - drop memory_region_get_ram_ptr(cmdmem) copy as it
>    should be migrated already ]
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>

I think we need to delay this until the PPI device has been added since 
this will extend the state of the CRB.


> ---
>   hw/tpm/tpm_crb.c | 32 +++++++++++++++++++++++++++++++-
>   1 file changed, 31 insertions(+), 1 deletion(-)
>
> diff --git a/hw/tpm/tpm_crb.c b/hw/tpm/tpm_crb.c
> index 908ca18d92..63d53384c5 100644
> --- a/hw/tpm/tpm_crb.c
> +++ b/hw/tpm/tpm_crb.c
> @@ -257,9 +257,39 @@ static enum TPMVersion tpm_crb_get_version(TPMIf *ti)
>       return tpm_backend_get_tpm_version(s->tpmbe);
>   }
>
> +/* persistent state handling */
> +
> +static int tpm_crb_pre_save(void *opaque)
> +{
> +    CRBState *s = opaque;
> +
> +    tpm_backend_finish_sync(s->tpmbe);
> +
> +    return 0;
> +}
> +
>   static const VMStateDescription vmstate_tpm_crb = {
>       .name = "tpm-crb",
> -    .unmigratable = 1,
> +    .pre_save  = tpm_crb_pre_save,
> +    .fields      = (VMStateField[]) {
> +        VMSTATE_UINT32(regs.loc_state.reg, CRBState),
> +        VMSTATE_UINT32(regs.loc_ctrl, CRBState),
> +        VMSTATE_UINT32(regs.loc_sts.reg, CRBState),
> +        VMSTATE_UINT64(regs.intf_id.reg, CRBState),
> +        VMSTATE_UINT64(regs.ctrl_ext, CRBState),
> +        VMSTATE_UINT32(regs.ctrl_req, CRBState),
> +        VMSTATE_UINT32(regs.ctrl_sts.reg, CRBState),
> +        VMSTATE_UINT32(regs.ctrl_cancel, CRBState),
> +        VMSTATE_UINT32(regs.ctrl_start, CRBState),
> +        VMSTATE_UINT32(regs.ctrl_int_enable, CRBState),
> +        VMSTATE_UINT32(regs.ctrl_int_sts, CRBState),
> +        VMSTATE_UINT32(regs.ctrl_cmd_size, CRBState),
> +        VMSTATE_UINT32(regs.ctrl_cmd_pa_low, CRBState),
> +        VMSTATE_UINT32(regs.ctrl_rsp_size, CRBState),
> +        VMSTATE_UINT64(regs.ctrl_rsp_pa, CRBState),
> +
> +        VMSTATE_END_OF_LIST(),
> +    }
>   };
>
>   static Property tpm_crb_properties[] = {