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

[Corey Minyard]

On 05/18/2018 10:45 AM, Marc-André Lureau wrote:
> 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.

That's probably fair.  I'll do that for v4.

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

Hmm.  That's a little hard.  I'll see what I can do.  Maybe it's not too 
bad,
most distros should have the openipmi library available.

> 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.

Yeah, I think we talked about subsections at one point, but this seemed 
better.
That will have to wait for David.

Thanks,

-corey

> > 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