iommu/vt-d: Fix ineffective devTLB invalidation for subdevices

mainline inclusion
from mainline-v5.11-rc3
commit 7c29ada5
category: bugfix
bugzilla: 108083
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c29ada5e70083805bc3a68daa23441df421fbee



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iommu_flush_dev_iotlb() is called to invalidate caches on a device but
only loops over the devices which are fully-attached to the domain. For
sub-devices, this is ineffective and can result in invalid caching
entries left on the device.

Fix the missing invalidation by adding a loop over the subdevices and
ensuring that 'domain->has_iotlb_device' is updated when attaching to
subdevices.

Fixes: 67b8e02b ("iommu/vt-d: Aux-domain specific domain attach/detach")
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/1609949037-25291-4-git-send-email-yi.l.liu@intel.com


Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>