iommu/amd: Invalidate cache before removing device from domain list

[ Upstream commit c362f32a59a84fe4453abecc6b53f5f70894a6d5 ]

Commit 87a6f1f22c97 ("iommu/amd: Introduce per-device domain ID to fix
potential TLB aliasing issue") introduced per device domain ID when
domain is configured with v2 page table. And in invalidation path, it
uses per device structure (dev_data->gcr3_info.domid) to get the domain ID.

In detach_device() path, current code tries to invalidate IOMMU cache
after removing dev_data from domain device list. This means when domain
is configured with v2 page table, amd_iommu_domain_flush_all() will not be
able to invalidate cache as device is already removed from domain device
list.

This is causing change domain tests (changing domain type from identity to DMA)
to fail with IO_PAGE_FAULT issue.

Hence invalidate cache and update DTE before updating data structures.

Reported-by: FahHean Lee <fahhean.lee@amd.com>
Reported-by: Dheeraj Kumar Srivastava <dheerajkumar.srivastava@amd.com>
Fixes: 87a6f1f22c97 ("iommu/amd: Introduce per-device domain ID to fix potential TLB aliasing issue")
Tested-by: Dheeraj Kumar Srivastava <dheerajkumar.srivastava@amd.com>
Tested-by: Sairaj Arun Kodilkar <sairaj.arunkodilkar@amd.com>
Tested-by: FahHean Lee <fahhean.lee@amd.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Link: https://lore.kernel.org/r/20240620060552.13984-1-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index d19a12a158085a0d6b178fbd915ef9854358778f..e2b900ffbc158e4d40e0697abfade113d6814ed0 100644 (file)
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2061,6 +2061,12 @@ static void do_detach(struct iommu_dev_data *dev_data)
        struct protection_domain *domain = dev_data->domain;
        struct amd_iommu *iommu = get_amd_iommu_from_dev_data(dev_data);
 
+       /* Clear DTE and flush the entry */
+       amd_iommu_dev_update_dte(dev_data, false);
+
+       /* Flush IOTLB and wait for the flushes to finish */
+       amd_iommu_domain_flush_all(domain);
+
        /* Clear GCR3 table */
        if (domain->pd_mode == PD_MODE_V2) {
                update_gcr3(dev_data, 0, 0, false);
@@ -2071,12 +2077,6 @@ static void do_detach(struct iommu_dev_data *dev_data)
        dev_data->domain = NULL;
        list_del(&dev_data->list);
 
-       /* Clear DTE and flush the entry */
-       amd_iommu_dev_update_dte(dev_data, false);
-
-       /* Flush IOTLB and wait for the flushes to finish */
-       amd_iommu_domain_flush_all(domain);
-
        /* decrease reference counters - needs to happen after the flushes */
        domain->dev_iommu[iommu->index] -= 1;
        domain->dev_cnt                 -= 1;