From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sean Christopherson Date: Wed, 08 Jan 2020 20:24:35 +0000 Subject: [PATCH 01/14] KVM: x86/mmu: Enforce max_level on HugeTLB mappings Message-Id: <20200108202448.9669-2-sean.j.christopherson@intel.com> List-Id: References: <20200108202448.9669-1-sean.j.christopherson@intel.com> In-Reply-To: <20200108202448.9669-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Paolo Bonzini Cc: Paul Mackerras , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Dave Hansen , Andy Lutomirski , Peter Zijlstra , Andrew Morton , Marc Zyngier , James Morse , Julien Thierry , Suzuki K Poulose , kvm-ppc@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, syzbot+c9d1fb51ac9d0d10c39d@syzkaller.appspotmail.com, Andrea Arcangeli , Barret Rhoden , David Hildenbrand , Jason Zeng , Liran Alon , linux-nvdimm Limit KVM's mapping level for HugeTLB based on its calculated max_level. The max_level check prior to invoking host_mapping_level() only filters out the case where KVM cannot create a 2mb mapping, it doesn't handle the scenario where KVM can create a 2mb but not 1gb mapping, and the host is using a 1gb HugeTLB mapping. Fixes: ad163aa8903d ("KVM: x86/mmu: Persist gfn_lpage_is_disallowed() to max_level") Signed-off-by: Sean Christopherson --- arch/x86/kvm/mmu/mmu.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 7269130ea5e2..8e822c09170d 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -1330,7 +1330,7 @@ gfn_to_memslot_dirty_bitmap(struct kvm_vcpu *vcpu, gfn_t gfn, static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn, int *max_levelp) { - int max_level = *max_levelp; + int host_level, max_level = *max_levelp; struct kvm_memory_slot *slot; if (unlikely(max_level = PT_PAGE_TABLE_LEVEL)) @@ -1362,7 +1362,8 @@ static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn, * So, do not propagate host_mapping_level() to max_level as KVM can * still promote the guest mapping to a huge page in the THP case. */ - return host_mapping_level(vcpu->kvm, large_gfn); + host_level = host_mapping_level(vcpu->kvm, large_gfn); + return min(host_level, max_level); } /* -- 2.24.1