From 68ce032a7d1c4db4c027a49922c53d08e5305b70 Mon Sep 17 00:00:00 2001 From: miaoyubo Date: Thu, 28 Jan 2021 10:00:04 +0800 Subject: [PATCH] KVM: Enable PUD huge mappings only on 1620 virt inclusion category: bugfix bugzilla: 47428 CVE: NA Disable PUD_SIZE huge mapping on 161x serial boards and only enable on 1620CS due to low performance on cache maintenance and complex implementation for pre-setup stage2 page table with PUD huge page. Which would even lead to hard lockup Signed-off-by: Zenghui Yu Signed-off-by: miaoyubo Reviewed-by: zhanghailiang Signed-off-by: Yang Yingliang --- virt/kvm/arm/mmu.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index 3a74cf59f5c8..b030bd3dce52 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1763,6 +1763,13 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, if (vma_pagesize == PMD_SIZE || (vma_pagesize == PUD_SIZE && kvm_stage2_has_pmd(kvm))) gfn = (fault_ipa & huge_page_mask(hstate_vma(vma))) >> PAGE_SHIFT; + + /* Only enable PUD_SIZE huge mapping on 1620 serial boards */ + if (vma_pagesize == PUD_SIZE && !kvm_ncsnp_support) { + vma_pagesize = PMD_SIZE; + gfn = (fault_ipa & PMD_MASK) >> PAGE_SHIFT; + } + up_read(¤t->mm->mmap_sem); /* We need minimum second+third level pages */ -- GitLab