Re: [Qemu-devel] [PATCH v3 2/3] ipmi: Use proper struct reference for KCS vmstate

[Marc-André Lureau]

Hi Corey

On Wed, Apr 25, 2018 at 5:27 PM,  <address@hidden> wrote:
> From: Corey Minyard <address@hidden>
>
> The vmstate for isa_ipmi_kcs was referencing into the kcs structure,
> instead create a kcs structure separate and use that.
>
> There were also some issues in the state transfer.  The inlen field
> was not being transferred, so if a transaction was in process during
> the transfer it would be messed up.  And the use_irq field was
> transferred, but that should come from the configuration.
>
> To fix this, the new VMS_VSTRUCT macros are used so the exact
> version of the structure can be specified, depending on what
> version was being received.  So an upgrade should work for KCS.

Looks good overall,

You could easily split this patch further to help review/bisecting etc.

Introduce VMSTATE_STRUCT, unuse use_irq, introduce version 2, add the
postload checks.

You could also help reviewers by giving your test setup, so we can
more easily reproduce the fix and/or try variants.

I also wonder if you could have used subsections, but the VSTRUCT type
seems a good approach to me, David would have to review it though.


> Signed-off-by: Corey Minyard <address@hidden>
> Cc: Dr. David Alan Gilbert <address@hidden>
> ---
>  hw/ipmi/isa_ipmi_kcs.c | 81 
> ++++++++++++++++++++++++++++++++++++++++----------
>  1 file changed, 66 insertions(+), 15 deletions(-)
>
> diff --git a/hw/ipmi/isa_ipmi_kcs.c b/hw/ipmi/isa_ipmi_kcs.c
> index 689587b..a794315 100644
> --- a/hw/ipmi/isa_ipmi_kcs.c
> +++ b/hw/ipmi/isa_ipmi_kcs.c
> @@ -22,6 +22,7 @@
>   * THE SOFTWARE.
>   */
>  #include "qemu/osdep.h"
> +#include "qemu/log.h"
>  #include "qapi/error.h"
>  #include "hw/hw.h"
>  #include "hw/ipmi/ipmi.h"
> @@ -422,24 +423,69 @@ static void ipmi_isa_realize(DeviceState *dev, Error 
> **errp)
>      isa_register_ioport(isadev, &iik->kcs.io, iik->kcs.io_base);
>  }
>
> -const VMStateDescription vmstate_ISAIPMIKCSDevice = {
> +static int ipmi_kcs_vmstate_post_load(void *opaque, int version)
> +{
> +    IPMIKCS *ik = opaque;
> +
> +    /* Make sure all the values are sane. */
> +    if (ik->outpos >= MAX_IPMI_MSG_SIZE || ik->outlen >= MAX_IPMI_MSG_SIZE ||
> +        ik->outpos >= ik->outlen) {
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                      "ipmi:kcs: vmstate transfer received bad out values: 
> %d %d\n",
> +                      ik->outpos, ik->outlen);
> +        ik->outpos = 0;
> +        ik->outlen = 0;
> +    }
> +
> +    if (ik->inlen >= MAX_IPMI_MSG_SIZE) {
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                      "ipmi:kcs: vmstate transfer received bad in value: 
> %d\n",
> +                      ik->inlen);
> +        ik->inlen = 0;
> +    }
> +
> +    return 0;
> +}
> +
> +static bool vmstate_kcs_before_version2(void *opaque, int version)
> +{
> +    return version <= 1;
> +}
> +
> +static const VMStateDescription vmstate_IPMIKCS = {
> +    .name = TYPE_IPMI_INTERFACE_PREFIX "kcs",
> +    .version_id = 2,
> +    .minimum_version_id = 1,
> +    .post_load = ipmi_kcs_vmstate_post_load,
> +    .fields      = (VMStateField[]) {
> +        VMSTATE_BOOL(obf_irq_set, IPMIKCS),
> +        VMSTATE_BOOL(atn_irq_set, IPMIKCS),
> +        VMSTATE_UNUSED_TEST(vmstate_kcs_before_version2, 1), /* Was use_irq 
> */
> +        VMSTATE_BOOL(irqs_enabled, IPMIKCS),
> +        VMSTATE_UINT32(outpos, IPMIKCS),
> +        VMSTATE_UINT32_V(outlen, IPMIKCS, 2),
> +        VMSTATE_UINT8_ARRAY(outmsg, IPMIKCS, MAX_IPMI_MSG_SIZE),
> +        VMSTATE_UINT32_V(inlen, IPMIKCS, 2),
> +        VMSTATE_UINT8_ARRAY(inmsg, IPMIKCS, MAX_IPMI_MSG_SIZE),
> +        VMSTATE_BOOL(write_end, IPMIKCS),
> +        VMSTATE_UINT8(status_reg, IPMIKCS),
> +        VMSTATE_UINT8(data_out_reg, IPMIKCS),
> +        VMSTATE_INT16(data_in_reg, IPMIKCS),
> +        VMSTATE_INT16(cmd_reg, IPMIKCS),
> +        VMSTATE_UINT8(waiting_rsp, IPMIKCS),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +static const VMStateDescription vmstate_ISAIPMIKCSDevice = {
>      .name = TYPE_IPMI_INTERFACE,
> -    .version_id = 1,
> +    .version_id = 2,
>      .minimum_version_id = 1,
>      .fields      = (VMStateField[]) {
> -        VMSTATE_BOOL(kcs.obf_irq_set, ISAIPMIKCSDevice),
> -        VMSTATE_BOOL(kcs.atn_irq_set, ISAIPMIKCSDevice),
> -        VMSTATE_BOOL(kcs.use_irq, ISAIPMIKCSDevice),
> -        VMSTATE_BOOL(kcs.irqs_enabled, ISAIPMIKCSDevice),
> -        VMSTATE_UINT32(kcs.outpos, ISAIPMIKCSDevice),
> -        VMSTATE_UINT8_ARRAY(kcs.outmsg, ISAIPMIKCSDevice, MAX_IPMI_MSG_SIZE),
> -        VMSTATE_UINT8_ARRAY(kcs.inmsg, ISAIPMIKCSDevice, MAX_IPMI_MSG_SIZE),
> -        VMSTATE_BOOL(kcs.write_end, ISAIPMIKCSDevice),
> -        VMSTATE_UINT8(kcs.status_reg, ISAIPMIKCSDevice),
> -        VMSTATE_UINT8(kcs.data_out_reg, ISAIPMIKCSDevice),
> -        VMSTATE_INT16(kcs.data_in_reg, ISAIPMIKCSDevice),
> -        VMSTATE_INT16(kcs.cmd_reg, ISAIPMIKCSDevice),
> -        VMSTATE_UINT8(kcs.waiting_rsp, ISAIPMIKCSDevice),
> +        VMSTATE_VSTRUCT_TEST(kcs, ISAIPMIKCSDevice, 
> vmstate_kcs_before_version2,
> +                             0, vmstate_IPMIKCS, IPMIKCS, 1),
> +        VMSTATE_VSTRUCT_V(kcs, ISAIPMIKCSDevice, 2, vmstate_IPMIKCS,
> +                          IPMIKCS, 2),
>          VMSTATE_END_OF_LIST()
>      }
>  };
> @@ -450,6 +496,11 @@ static void isa_ipmi_kcs_init(Object *obj)
>
>      ipmi_bmc_find_and_link(obj, (Object **) &iik->kcs.bmc);
>
> +    /*
> +     * Version 1 had an incorrect name, it clashed with the BT
> +     * IPMI device, so receive it, but transmit a different
> +     * version.
> +     */
>      vmstate_register(NULL, 0, &vmstate_ISAIPMIKCSDevice, iik);
>  }
>
> --
> 2.7.4
>
>



-- 
Marc-André Lureau