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| author | Jacob Pan <jacob.jun.pan@linux.intel.com> | 2023-02-16 16:08:15 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-03-17 10:32:50 +0300 |
| commit | 1b48c70feefc499b62670521efa002ab01e05df5 (patch) | |
| tree | a29ee81b652ae301f64f69167cbc2b84765712b5 /drivers | |
| parent | 985d9fa06b4b90f67e18e4ae3573421406ef253e (diff) | |
| download | linux-1b48c70feefc499b62670521efa002ab01e05df5.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')
| -rw-r--r-- | drivers/iommu/intel-pasid.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/iommu/intel-pasid.c b/drivers/iommu/intel-pasid.c index e7cb0b8a7332..58f060006ba3 100644 --- a/drivers/iommu/intel-pasid.c +++ b/drivers/iommu/intel-pasid.c @@ -166,6 +166,9 @@ 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; } @@ -250,6 +253,10 @@ struct pasid_entry *intel_pasid_get_entry(struct device *dev, int pasid) WRITE_ONCE(dir[dir_index].val, (u64)virt_to_phys(entries) | PASID_PTE_PRESENT); + if (!ecap_coherent(info->iommu->ecap)) { + clflush_cache_range(entries, VTD_PAGE_SIZE); + clflush_cache_range(&dir[dir_index].val, sizeof(*dir)); + } } spin_unlock(&pasid_lock); |