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authorJacob Pan <jacob.jun.pan@linux.intel.com>2023-02-16 16:08:15 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2023-03-17 10:45:08 +0300
commit7e00b52c8cdd9d3a985d63d72ecae7bde6314883 (patch)
treead5c9f53222da7f1c518b59bd2248996994597e2 /drivers/iommu
parentc424b1819120093d34852c5893c507a4bc0b5a98 (diff)
downloadlinux-7e00b52c8cdd9d3a985d63d72ecae7bde6314883.tar.xz
iommu/vt-d: Fix PASID directory pointer coherency
[ Upstream commit 194b3348bdbb7db65375c72f3f774aee4cc6614e ] On platforms that do not support IOMMU Extended capability bit 0 Page-walk Coherency, CPU caches are not snooped when IOMMU is accessing any translation structures. IOMMU access goes only directly to memory. Intel IOMMU code was missing a flush for the PASID table directory that resulted in the unrecoverable fault as shown below. This patch adds clflush calls whenever allocating and updating a PASID table directory to ensure cache coherency. On the reverse direction, there's no need to clflush the PASID directory pointer when we deactivate a context entry in that IOMMU hardware will not see the old PASID directory pointer after we clear the context entry. PASID directory entries are also never freed once allocated. DMAR: DRHD: handling fault status reg 3 DMAR: [DMA Read NO_PASID] Request device [00:0d.2] fault addr 0x1026a4000 [fault reason 0x51] SM: Present bit in Directory Entry is clear DMAR: Dump dmar1 table entries for IOVA 0x1026a4000 DMAR: scalable mode root entry: hi 0x0000000102448001, low 0x0000000101b3e001 DMAR: context entry: hi 0x0000000000000000, low 0x0000000101b4d401 DMAR: pasid dir entry: 0x0000000101b4e001 DMAR: pasid table entry[0]: 0x0000000000000109 DMAR: pasid table entry[1]: 0x0000000000000001 DMAR: pasid table entry[2]: 0x0000000000000000 DMAR: pasid table entry[3]: 0x0000000000000000 DMAR: pasid table entry[4]: 0x0000000000000000 DMAR: pasid table entry[5]: 0x0000000000000000 DMAR: pasid table entry[6]: 0x0000000000000000 DMAR: pasid table entry[7]: 0x0000000000000000 DMAR: PTE not present at level 4 Cc: <stable@vger.kernel.org> Fixes: 0bbeb01a4faf ("iommu/vt-d: Manage scalalble mode PASID tables") Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reported-by: Sukumar Ghorai <sukumar.ghorai@intel.com> Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Link: https://lore.kernel.org/r/20230209212843.1788125-1-jacob.jun.pan@linux.intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/iommu')
-rw-r--r--drivers/iommu/intel/pasid.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c
index f821153390e5..80d6412e2c54 100644
--- a/drivers/iommu/intel/pasid.c
+++ b/drivers/iommu/intel/pasid.c
@@ -186,6 +186,9 @@ int intel_pasid_alloc_table(struct device *dev)
attach_out:
device_attach_pasid_table(info, pasid_table);
+ if (!ecap_coherent(info->iommu->ecap))
+ clflush_cache_range(pasid_table->table, size);
+
return 0;
}
@@ -276,6 +279,10 @@ retry:
free_pgtable_page(entries);
goto retry;
}
+ if (!ecap_coherent(info->iommu->ecap)) {
+ clflush_cache_range(entries, VTD_PAGE_SIZE);
+ clflush_cache_range(&dir[dir_index].val, sizeof(*dir));
+ }
}
return &entries[index];