From: Greg KH on
2.6.33-stable review patch. If anyone has any objections, please let us know.

------------------

From: Chris Wright <chrisw(a)sous-sol.org>

commit 04e856c072b84042bb56c487c2868638bb3f78db upstream.

After a guest is shutdown, assigned devices are not properly
returned to the pt domain. This can leave the device using
stale cached IOMMU data, and result in a non-functional
device after it's re-bound to the host driver. For example,
I see this upon rebinding:

AMD-Vi: Event logged [IO_PAGE_FAULT device=02:00.0 domain=0x0000 address=0x000000007e2a8000 flags=0x0050]
AMD-Vi: Event logged [IO_PAGE_FAULT device=02:00.0 domain=0x0000 address=0x000000007e2a8040 flags=0x0050]
AMD-Vi: Event logged [IO_PAGE_FAULT device=02:00.0 domain=0x0000 address=0x000000007e2a8080 flags=0x0050]
AMD-Vi: Event logged [IO_PAGE_FAULT device=02:00.0 domain=0x0000 address=0x000000007e2a80c0 flags=0x0050]
0000:02:00.0: eth2: Detected Hardware Unit Hang:
...

The amd_iommu_destroy_domain() function calls do_detach()
which doesn't reattach the pt domain to the device.
Use __detach_device() instead.

Signed-off-by: Chris Wright <chrisw(a)sous-sol.org>
Signed-off-by: Joerg Roedel <joerg.roedel(a)amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)suse.de>

---
arch/x86/kernel/amd_iommu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -2298,7 +2298,7 @@ static void cleanup_domain(struct protec
list_for_each_entry_safe(dev_data, next, &domain->dev_list, list) {
struct device *dev = dev_data->dev;

- do_detach(dev);
+ __detach_device(dev);
atomic_set(&dev_data->bind, 0);
}



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