diff options
Diffstat (limited to 'arch/x86/kvm/mmu.c')
-rw-r--r-- | arch/x86/kvm/mmu.c | 21 |
1 files changed, 11 insertions, 10 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 6248c39a33ef..15d2c06d7fec 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Kernel-based Virtual Machine driver for Linux * @@ -12,10 +13,6 @@ * Authors: * Yaniv Kamay <yaniv@qumranet.com> * Avi Kivity <avi@qumranet.com> - * - * This work is licensed under the terms of the GNU GPL, version 2. See - * the COPYING file in the top-level directory. - * */ #include "irq.h" @@ -5606,14 +5603,18 @@ static int alloc_mmu_pages(struct kvm_vcpu *vcpu) struct page *page; int i; - if (tdp_enabled) - return 0; - /* - * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64. - * Therefore we need to allocate shadow page tables in the first - * 4GB of memory, which happens to fit the DMA32 zone. + * When using PAE paging, the four PDPTEs are treated as 'root' pages, + * while the PDP table is a per-vCPU construct that's allocated at MMU + * creation. When emulating 32-bit mode, cr3 is only 32 bits even on + * x86_64. Therefore we need to allocate the PDP table in the first + * 4GB of memory, which happens to fit the DMA32 zone. Except for + * SVM's 32-bit NPT support, TDP paging doesn't use PAE paging and can + * skip allocating the PDP table. */ + if (tdp_enabled && kvm_x86_ops->get_tdp_level(vcpu) > PT32E_ROOT_LEVEL) + return 0; + page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_DMA32); if (!page) return -ENOMEM; |