From cbf3ccd09d683abf1cacd36e3640872ee912d99b Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Tue, 20 Oct 2015 14:59:36 +0200 Subject: [PATCH] iommu/amd: Don't clear DTE flags when modifying it 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 Tested-by: G. Richard Bellamy Cc: stable@vger.kernel.org Signed-off-by: Joerg Roedel --- drivers/iommu/amd_iommu.c | 4 ++-- drivers/iommu/amd_iommu_types.h | 1 + 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 08d2775887f7..532e2a211fe1 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -1974,8 +1974,8 @@ 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 f65908841be0..c9b64722f623 100644 --- a/drivers/iommu/amd_iommu_types.h +++ b/drivers/iommu/amd_iommu_types.h @@ -295,6 +295,7 @@ #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) -- 2.20.1