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authorJoerg Roedel <jroedel@suse.de>2015-10-20 14:59:36 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2015-11-09 12:50:24 -0800
commit5d20bbde895c0353f5099131ef60ee62ba95dee6 (patch)
tree04734dba9ce2e46696a043671f535efcf6e2061f
parent0caf59c93d8a6e3bb568b1b2d590b11109d125e7 (diff)
downloadlwn-5d20bbde895c0353f5099131ef60ee62ba95dee6.tar.gz
lwn-5d20bbde895c0353f5099131ef60ee62ba95dee6.zip
iommu/amd: Don't clear DTE flags when modifying it
commit cbf3ccd09d683abf1cacd36e3640872ee912d99b upstream. During device assignment/deassignment the flags in the DTE get lost, which might cause spurious faults, for example when the device tries to access the system management range. Fix this by not clearing the flags with the rest of the DTE. Reported-by: G. Richard Bellamy <rbellamy@pteradigm.com> Tested-by: G. Richard Bellamy <rbellamy@pteradigm.com> Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/iommu/amd_iommu.c4
-rw-r--r--drivers/iommu/amd_iommu_types.h1
2 files changed, 3 insertions, 2 deletions
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 935974090aa0..b0cb66208c8b 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -2152,8 +2152,8 @@ static void set_dte_entry(u16 devid, struct protection_domain *domain, bool ats)
static void clear_dte_entry(u16 devid)
{
/* remove entry from the device table seen by the hardware */
- amd_iommu_dev_table[devid].data[0] = IOMMU_PTE_P | IOMMU_PTE_TV;
- amd_iommu_dev_table[devid].data[1] = 0;
+ amd_iommu_dev_table[devid].data[0] = IOMMU_PTE_P | IOMMU_PTE_TV;
+ amd_iommu_dev_table[devid].data[1] &= DTE_FLAG_MASK;
amd_iommu_apply_erratum_63(devid);
}
diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index e400fbe411de..e0c39940f659 100644
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -283,6 +283,7 @@
#define IOMMU_PTE_IR (1ULL << 61)
#define IOMMU_PTE_IW (1ULL << 62)
+#define DTE_FLAG_MASK (0x3ffULL << 32)
#define DTE_FLAG_IOTLB (0x01UL << 32)
#define DTE_FLAG_GV (0x01ULL << 55)
#define DTE_GLX_SHIFT (56)