[libvirt] [PATCH v3 2/4] qemu: add dtb capability

[Eric Blake]

On 02/27/2013 09:56 AM, Eric Blake wrote:

>> @@ -944,6 +945,8 @@ virQEMUCapsComputeCmdFlags(const char *help,
>>      }
>>      if (strstr(help, "-uuid"))
>>          virQEMUCapsSet(qemuCaps, QEMU_CAPS_UUID);
>> +    if (strstr(help, "-dtb"))
>> +        virQEMUCapsSet(qemuCaps, QEMU_CAPS_DTB);
> 
> This won't work.  -dtb did not exist prior to qemu 1.2, and for all qemu
> newer than 1.2, we do NOT scrape '-help' output; instead, we use QMP
> query commands.  You need to figure out the corresponding QMP command
> that we can use to tell when dtb support exists in qemu.

I stand (slightly) corrected: it looks like -dtb was added in qemu 1.1
(qemu commit 379b5c7), which means we DO need -help scraping for that
version of qemu.  Then, since it predates when QMP queries are reliable,
you can get away with blindly setting QEMU_CAPS_DTB when targetting a
qemu new enough to support QMP queries without actually having to query
for it.  But it's still something to be fixed before this patch is ready :)

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 621 bytes
Desc: OpenPGP digital signature
URL: <http://listman.redhat.com/archives/libvir-list/attachments/20130227/087c9932/attachment-0001.sig>