This is a note to let you know that I've just added the patch titled arm/arm64: KVM: Take mmap_sem in stage2_unmap_vm to the 4.10-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: arm-arm64-kvm-take-mmap_sem-in-stage2_unmap_vm.patch and it can be found in the queue-4.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 90f6e150e44a0dc3883110eeb3ab35d1be42b6bb Mon Sep 17 00:00:00 2001 From: Marc Zyngier <marc.zyngier@xxxxxxx> Date: Thu, 16 Mar 2017 18:20:49 +0000 Subject: arm/arm64: KVM: Take mmap_sem in stage2_unmap_vm From: Marc Zyngier <marc.zyngier@xxxxxxx> commit 90f6e150e44a0dc3883110eeb3ab35d1be42b6bb upstream. We don't hold the mmap_sem while searching for the VMAs when we try to unmap each memslot for a VM. Fix this properly to avoid unexpected results. Fixes: commit 957db105c997 ("arm/arm64: KVM: Introduce stage2_unmap_vm") Reviewed-by: Christoffer Dall <cdall@xxxxxxxxxx> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx> Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arm/kvm/mmu.c | 2 ++ 1 file changed, 2 insertions(+) --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -803,6 +803,7 @@ void stage2_unmap_vm(struct kvm *kvm) int idx; idx = srcu_read_lock(&kvm->srcu); + down_read(¤t->mm->mmap_sem); spin_lock(&kvm->mmu_lock); slots = kvm_memslots(kvm); @@ -810,6 +811,7 @@ void stage2_unmap_vm(struct kvm *kvm) stage2_unmap_memslot(kvm, memslot); spin_unlock(&kvm->mmu_lock); + up_read(¤t->mm->mmap_sem); srcu_read_unlock(&kvm->srcu, idx); } Patches currently in stable-queue which might be from marc.zyngier@xxxxxxx are queue-4.10/kvm-arm-arm64-fix-locking-for-kvm_free_stage2_pgd.patch queue-4.10/arm-arm64-kvm-take-mmap_sem-in-kvm_arch_prepare_memory_region.patch queue-4.10/arm-arm64-kvm-take-mmap_sem-in-stage2_unmap_vm.patch