Re: [PULL 02/19] sev: update sev-inject-launch-secret to make gpa optional

[James Bottomley]

On Thu, 2021-05-20 at 23:36 +0200, Philippe Mathieu-Daudé wrote:
> On 2/15/21 2:16 PM, Paolo Bonzini wrote:
> > From: James Bottomley <jejb@linux.ibm.com>
> > 
> > If the gpa isn't specified, it's value is extracted from the OVMF
> > properties table located below the reset vector (and if this
> > doesn't
> > exist, an error is returned).  OVMF has defined the GUID for the
> > SEV
> > secret area as 4c2eb361-7d9b-4cc3-8081-127c90d3d294 and the format
> > of
> > the <data> is: <base>|<size> where both are uint32_t.  We extract
> > <base> and use it as the gpa for the injection.
> > 
> > Note: it is expected that the injected secret will also be GUID
> > described but since qemu can't interpret it, the format is left
> > undefined here.
> > 
> > Signed-off-by: James Bottomley <jejb@linux.ibm.com>
> > 
> > Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> > Message-Id: <20210204193939.16617-3-jejb@linux.ibm.com>
> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> > ---
> >  qapi/misc-target.json |  2 +-
> >  target/i386/monitor.c | 23 ++++++++++++++++++++++-
> >  2 files changed, 23 insertions(+), 2 deletions(-)
> > 
> > diff --git a/qapi/misc-target.json b/qapi/misc-target.json
> > index 06ef8757f0..0c7491cd82 100644
> > --- a/qapi/misc-target.json
> > +++ b/qapi/misc-target.json
> > @@ -216,7 +216,7 @@
> >  #
> >  ##
> >  { 'command': 'sev-inject-launch-secret',
> > -  'data': { 'packet-header': 'str', 'secret': 'str', 'gpa':
> > 'uint64' },
> > +  'data': { 'packet-header': 'str', 'secret': 'str', '*gpa':
> > 'uint64' },
> >    'if': 'defined(TARGET_I386)' }
> >  
> >  ##
> > diff --git a/target/i386/monitor.c b/target/i386/monitor.c
> > index 1bc91442b1..5994408bee 100644
> > --- a/target/i386/monitor.c
> > +++ b/target/i386/monitor.c
> > @@ -34,6 +34,7 @@
> >  #include "sev_i386.h"
> >  #include "qapi/qapi-commands-misc-target.h"
> >  #include "qapi/qapi-commands-misc.h"
> > +#include "hw/i386/pc.h"
> >  
> >  /* Perform linear address sign extension */
> >  static hwaddr addr_canonical(CPUArchState *env, hwaddr addr)
> > @@ -730,9 +731,29 @@ SevCapability
> > *qmp_query_sev_capabilities(Error **errp)
> >      return sev_get_capabilities(errp);
> >  }
> >  
> > +#define SEV_SECRET_GUID "4c2eb361-7d9b-4cc3-8081-127c90d3d294"
> > +struct sev_secret_area {
> > +    uint32_t base;
> > +    uint32_t size;
> > +};
> > +
> >  void qmp_sev_inject_launch_secret(const char *packet_hdr,
> > -                                  const char *secret, uint64_t
> > gpa,
> > +                                  const char *secret,
> > +                                  bool has_gpa, uint64_t gpa,
> >                                    Error **errp)
> >  {
> > +    if (!has_gpa) {
> > +        uint8_t *data;
> > +        struct sev_secret_area *area;
> > +
> > +        if (!pc_system_ovmf_table_find(SEV_SECRET_GUID, &data,
> > NULL)) {
> 
> FYI trying to build MicroVM standalone (--without-default-devices):
> 
> /usr/bin/ld: libqemu-i386-softmmu.fa.p/target_i386_monitor.c.o: in
> function `qmp_sev_inject_launch_secret':
> target/i386/monitor.c:749: undefined reference to
> `pc_system_ovmf_table_find'
> 
> I'm adding this to my TODO list.

I'm pretty clueless with the new meson build system but I think this is
something to do with CONFIG_PC not being defined ... can you verify? in
which case it could be fixed with a pc_sysfw-stub.c that builds it as a
function returning false.

James