[libvirt] [PATCHv4 2/2] qemu: eliminate "Ignoring open failure" when using root-squash NFS

Laine Stump laine at laine.org
Fri Feb 3 21:50:11 UTC 2012


On 02/03/2012 03:45 PM, Eric Blake wrote:
> On 02/01/2012 11:36 PM, Laine Stump wrote:
>> This eliminates the warning message reported in:
>>
>>   https://bugzilla.redhat.com/show_bug.cgi?id=624447
>>
>> It was caused by a failure to open an image file that is not
>> accessible by root (the uid libvirtd is running as) because it's on a
>> root-squash NFS share, owned by a different user, with permissions of
>> 660 (or maybe 600).
>>
>> The solution is to use virFileOpenAs() rather than open(). The
>> codepath that generates the error is during qemuSetupDiskCGroup(), but
>> the actual open() is in a lower-level generic function called from
>> many places (virDomainDiskDefForeachPath), so some other pieces of the
>> code were touched just to add dummy (or possibly useful) uid and gid
>> arguments.
>>
>> Eliminating this warning message has the nice side effect that the
>> requested operation may even succeed (which in this case isn't
>> necessary, but shouldn't hurt anything either).
>> ---
>>   src/conf/domain_conf.c          |    8 ++++----
>>   src/conf/domain_conf.h          |    1 +
>>   src/qemu/qemu_cgroup.c          |    2 ++
>>   src/security/security_dac.c     |    1 +
>>   src/security/security_selinux.c |    7 +++++++
>>   src/security/virt-aa-helper.c   |    6 +++++-
>>   6 files changed, 20 insertions(+), 5 deletions(-)
> After all that churn on 1/2, this one has just been patiently waiting,
> unchanged.  That shows that once we get a good interface, using it is
> easier.
>
> ACK.

And hopefully we can use it to clear up some other similar problems.

Pushed. Thanks!




More information about the libvir-list mailing list