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| author | Lu Baolu <baolu.lu@linux.intel.com> | 2019-03-20 04:58:33 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-04-27 10:30:28 +0300 |
| commit | 13ad4729e6865cbb088f13e5b4cc4e5f0e8f1ad0 (patch) | |
| tree | 27dfa1c16d865ac0659be7a973251a2ed3c9f813 /drivers | |
| parent | d7201786ea98befea83f0e54e43ea76f4f10c3e6 (diff) | |
| download | linux-13ad4729e6865cbb088f13e5b4cc4e5f0e8f1ad0.tar.xz | |
iommu/vt-d: Check capability before disabling protected memory
[ Upstream commit 5bb71fc790a88d063507dc5d445ab8b14e845591 ]
The spec states in 10.4.16 that the Protected Memory Enable
Register should be treated as read-only for implementations
not supporting protected memory regions (PLMR and PHMR fields
reported as Clear in the Capability register).
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: mark gross <mgross@intel.com>
Suggested-by: Ashok Raj <ashok.raj@intel.com>
Fixes: f8bab73515ca5 ("intel-iommu: PMEN support")
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-iommu.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 2068cb59f7ed..b1966269f26a 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -1402,6 +1402,9 @@ static void iommu_disable_protect_mem_regions(struct intel_iommu *iommu) u32 pmen; unsigned long flags; + if (!cap_plmr(iommu->cap) && !cap_phmr(iommu->cap)) + return; + raw_spin_lock_irqsave(&iommu->register_lock, flags); pmen = readl(iommu->reg + DMAR_PMEN_REG); pmen &= ~DMA_PMEN_EPM; |