From: Joerg Roedel Date: Tue, 20 Oct 2015 12:59:36 +0000 (+0200) Subject: iommu/amd: Don't clear DTE flags when modifying it X-Git-Tag: v4.2.6~95 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ec14245c8839c2c896828944b7ad91799290591e;p=thirdparty%2Fkernel%2Fstable.git 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 Tested-by: G. Richard Bellamy Signed-off-by: Joerg Roedel Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 658ee39e65696..1b10e5fd6ef6c 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 f65908841be01..c9b64722f6230 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)