recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.19/0001-KVM-mmu_notifier-Flush-TLBs-before-releasing-mmu_loc.patch

   1 From e29e69cb6dff635429cbda9a9548c3d0390689f9 Mon Sep 17 00:00:00 2001
   2 From: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
   3 Date: Fri, 10 Feb 2012 15:28:31 +0900
   4 Subject: [PATCH 001/117] KVM: mmu_notifier: Flush TLBs before releasing
   5  mmu_lock
   6
   7 (cherry picked from commit 565f3be2174611f364405bbea2d86e153c2e7e78
   8
   9 Other threads may process the same page in that small window and skip
  10 TLB flush and then return before these functions do flush.
  11
  12 Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
  13 Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
  14 Signed-off-by: Avi Kivity <avi@redhat.com>
  15 Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
  16 ---
  17  virt/kvm/kvm_main.c |   19 ++++++++++---------
  18  1 file changed, 10 insertions(+), 9 deletions(-)
  19
  20 diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
  21 index e401c1b..9ffac2e 100644
  22 --- a/virt/kvm/kvm_main.c
  23 +++ b/virt/kvm/kvm_main.c
  24 @@ -289,15 +289,15 @@ static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
  25          */
  26         idx = srcu_read_lock(&kvm->srcu);
  27         spin_lock(&kvm->mmu_lock);
  28 +
  29         kvm->mmu_notifier_seq++;
  30         need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty;
  31 -       spin_unlock(&kvm->mmu_lock);
  32 -       srcu_read_unlock(&kvm->srcu, idx);
  33 -
  34         /* we've to flush the tlb before the pages can be freed */
  35         if (need_tlb_flush)
  36                 kvm_flush_remote_tlbs(kvm);
  37
  38 +       spin_unlock(&kvm->mmu_lock);
  39 +       srcu_read_unlock(&kvm->srcu, idx);
  40  }
  41
  42  static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
  43 @@ -335,12 +335,12 @@ static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
  44         for (; start < end; start += PAGE_SIZE)
  45                 need_tlb_flush |= kvm_unmap_hva(kvm, start);
  46         need_tlb_flush |= kvm->tlbs_dirty;
  47 -       spin_unlock(&kvm->mmu_lock);
  48 -       srcu_read_unlock(&kvm->srcu, idx);
  49 -
  50         /* we've to flush the tlb before the pages can be freed */
  51         if (need_tlb_flush)
  52                 kvm_flush_remote_tlbs(kvm);
  53 +
  54 +       spin_unlock(&kvm->mmu_lock);
  55 +       srcu_read_unlock(&kvm->srcu, idx);
  56  }
  57
  58  static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
  59 @@ -378,13 +378,14 @@ static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
  60
  61         idx = srcu_read_lock(&kvm->srcu);
  62         spin_lock(&kvm->mmu_lock);
  63 -       young = kvm_age_hva(kvm, address);
  64 -       spin_unlock(&kvm->mmu_lock);
  65 -       srcu_read_unlock(&kvm->srcu, idx);
  66
  67 +       young = kvm_age_hva(kvm, address);
  68         if (young)
  69                 kvm_flush_remote_tlbs(kvm);
  70
  71 +       spin_unlock(&kvm->mmu_lock);
  72 +       srcu_read_unlock(&kvm->srcu, idx);
  73 +
  74         return young;
  75  }
  76
  77 --
  78 1.7.9.5
  79