This is a note to let you know that I've just added the patch titled iommu/amd: Don't clear DTE flags when modifying it to the 4.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: iommu-amd-don-t-clear-dte-flags-when-modifying-it.patch and it can be found in the queue-4.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From cbf3ccd09d683abf1cacd36e3640872ee912d99b Mon Sep 17 00:00:00 2001 From: Joerg Roedel <jroedel@xxxxxxx> Date: Tue, 20 Oct 2015 14:59:36 +0200 Subject: iommu/amd: Don't clear DTE flags when modifying it From: Joerg Roedel <jroedel@xxxxxxx> 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@xxxxxxxxxxxxx> Tested-by: G. Richard Bellamy <rbellamy@xxxxxxxxxxxxx> Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/iommu/amd_iommu.c | 4 ++-- drivers/iommu/amd_iommu_types.h | 1 + 2 files changed, 3 insertions(+), 2 deletions(-) --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -2099,8 +2099,8 @@ static void set_dte_entry(u16 devid, str 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); } --- 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) Patches currently in stable-queue which might be from jroedel@xxxxxxx are queue-4.1/iommu-amd-fix-bug-when-faulting-a-prot_none-vma.patch queue-4.1/iommu-amd-don-t-clear-dte-flags-when-modifying-it.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html