releases/4.9.175/iommu-amd-set-exclusion-range-correctly.patch

   1 From c5a45c25141ee6be666e25c122bfc00a94057e11 Mon Sep 17 00:00:00 2001
   2 From: Joerg Roedel <jroedel@suse.de>
   3 Date: Fri, 12 Apr 2019 12:50:31 +0200
   4 Subject: iommu/amd: Set exclusion range correctly
   5
   6 [ Upstream commit 3c677d206210f53a4be972211066c0f1cd47fe12 ]
   7
   8 The exlcusion range limit register needs to contain the
   9 base-address of the last page that is part of the range, as
  10 bits 0-11 of this register are treated as 0xfff by the
  11 hardware for comparisons.
  12
  13 So correctly set the exclusion range in the hardware to the
  14 last page which is _in_ the range.
  15
  16 Fixes: b2026aa2dce44 ('x86, AMD IOMMU: add functions for programming IOMMU MMIO space')
  17 Signed-off-by: Joerg Roedel <jroedel@suse.de>
  18 Signed-off-by: Sasha Levin <sashal@kernel.org>
  19 ---
  20  drivers/iommu/amd_iommu_init.c | 2 +-
  21  1 file changed, 1 insertion(+), 1 deletion(-)
  22
  23 diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
  24 index 157e93421fb81..13bbe5795e4e4 100644
  25 --- a/drivers/iommu/amd_iommu_init.c
  26 +++ b/drivers/iommu/amd_iommu_init.c
  27 @@ -318,7 +318,7 @@ static void iommu_write_l2(struct amd_iommu *iommu, u8 address, u32 val)
  28  static void iommu_set_exclusion_range(struct amd_iommu *iommu)
  29  {
  30         u64 start = iommu->exclusion_start & PAGE_MASK;
  31 -       u64 limit = (start + iommu->exclusion_length) & PAGE_MASK;
  32 +       u64 limit = (start + iommu->exclusion_length - 1) & PAGE_MASK;
  33         u64 entry;
  34
  35         if (!iommu->exclusion_start)
  36 --
  37 2.20.1
  38