Messages in this thread Patch in this message | | | Date | Wed, 28 Jan 2015 14:38:52 +0000 | From | Will Deacon <> | Subject | Re: [PATCH 4/5] iommu: Make sure a device is always attached to a domain |
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On Tue, Jan 27, 2015 at 12:08:58AM +0000, Joerg Roedel wrote: > From: Joerg Roedel <jroedel@suse.de> > > Make use of the default domain and re-attach a device to it > when it is detached from another domain. Also enforce that a > device has to be in the default domain before it can be > attached to a different domain. > > Signed-off-by: Joerg Roedel <jroedel@suse.de> > --- > drivers/iommu/iommu.c | 34 +++++++++++++++++++++++++++++++--- > 1 file changed, 31 insertions(+), 3 deletions(-) > > diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c > index b63a550..5080759 100644 > --- a/drivers/iommu/iommu.c > +++ b/drivers/iommu/iommu.c > @@ -53,6 +53,7 @@ struct iommu_group { > int id; > unsigned dev_cnt; > struct iommu_domain *default_domain; > + struct iommu_domain *domain; > }; > > struct iommu_device { > @@ -1040,8 +1041,17 @@ static int iommu_group_do_attach_device(struct device *dev, void *data) > > int iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group) > { > - return iommu_group_for_each_dev(group, domain, > - iommu_group_do_attach_device); > + int ret; > + > + if (group->default_domain && group->domain != group->default_domain) > + return -EBUSY;
I think this is now racy with itself and detach, whereas before we always held the group->mutex by virtue of iommu_group_for_each_dev.
Will
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