[libvirt] [PATCH] qemu_conf: Properly mark driver->config as self-locking APIs

[Daniel P. Berrange]

On Wed, Jul 17, 2013 at 12:32:57PM +0200, Michal Privoznik wrote:
> On 17.07.2013 11:46, Daniel P. Berrange wrote:
> > On Tue, Jul 16, 2013 at 08:25:25PM +0200, Michal Privoznik wrote:
> >> Since a9e97e0c we don't require driver->config, or
> >> virQEMUDriverGetConfig() to be called with locked QEMU driver. In fact,
> >> calling it with the driver locked would cause deadlock. Hence, the
> >> annotation to the struct field is not right.
> >> ---
> >>  src/qemu/qemu_conf.h | 3 +--
> >>  1 file changed, 1 insertion(+), 2 deletions(-)
> >>
> >> diff --git a/src/qemu/qemu_conf.h b/src/qemu/qemu_conf.h
> >> index 8229cfc..fd5cc57 100644
> >> --- a/src/qemu/qemu_conf.h
> >> +++ b/src/qemu/qemu_conf.h
> >> @@ -160,8 +160,7 @@ struct _virQEMUDriverConfig {
> >>  struct _virQEMUDriver {
> >>      virMutex lock;
> >>  
> >> -    /* Require lock to get reference on 'config',
> >> -     * then lockless thereafter */
> >> +    /* Immutable pointer, self-locking APIs */
> >>      virQEMUDriverConfigPtr config;
> > 
> > Actually, it is  'immutable pointer, immutable+lockless data', since
> > we don't require any locks to be held in order to access fields in
> > the config object.
> > 
> > Regards,
> > Daniel
> > 
> 
> Consider this squashed in:
> 
> diff --git a/src/lxc/lxc_container.c b/src/lxc/lxc_container.c
> index 37d2ba6..ca8a39e 100644
> --- a/src/lxc/lxc_container.c
> +++ b/src/lxc/lxc_container.c
> @@ -357,7 +357,7 @@ static int lxcContainerSetID(virDomainDefPtr def)
> 
>      VIR_DEBUG("Set UID/GID to 0/0");
>      if (def->idmap.nuidmap &&
> -        virSetUIDGID(0, 0, groups, ngroups) < 0) {
> +        virSetUIDGID(0, 0, NULL, 0) < 0) {
>          virReportSystemError(errno, "%s",
>                               _("setuid or setgid failed"));
>          return -1;

You replied to the wrong message :-) But ACK to the patch since I know
what you meant to reply to.

Daniel
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