From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757170AbcBXNXP (ORCPT ); Wed, 24 Feb 2016 08:23:15 -0500 Received: from mail-wm0-f67.google.com ([74.125.82.67]:34374 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754744AbcBXNSB (ORCPT ); Wed, 24 Feb 2016 08:18:01 -0500 From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: yoshikawa_takuya_b1@lab.ntt.co.jp, guangrong.xiao@linux.intel.com, mtosatti@redhat.com Subject: [PATCH 02/12] KVM: MMU: check kvm_mmu_pages and mmu_page_path indices Date: Wed, 24 Feb 2016 14:17:43 +0100 Message-Id: <1456319873-34182-3-git-send-email-pbonzini@redhat.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1456319873-34182-1-git-send-email-pbonzini@redhat.com> References: <1456319873-34182-1-git-send-email-pbonzini@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xiao Guangrong Give a special invalid index to the root of the walk, so that we can check the consistency of kvm_mmu_pages and mmu_page_path. Signed-off-by: Xiao Guangrong [Extracted from a bigger patch proposed by Guangrong. - Paolo] Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 4dee855897cf..3060873d8cab 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1840,6 +1840,8 @@ static int __mmu_unsync_walk(struct kvm_mmu_page *sp, return nr_unsync_leaf; } +#define INVALID_INDEX (-1) + static int mmu_unsync_walk(struct kvm_mmu_page *sp, struct kvm_mmu_pages *pvec) { @@ -1847,7 +1849,7 @@ static int mmu_unsync_walk(struct kvm_mmu_page *sp, if (!sp->unsync_children) return 0; - mmu_pages_add(pvec, sp, 0); + mmu_pages_add(pvec, sp, INVALID_INDEX); return __mmu_unsync_walk(sp, pvec); } @@ -1996,6 +1998,8 @@ static int mmu_pages_first(struct kvm_mmu_pages *pvec, if (pvec->nr == 0) return 0; + WARN_ON(pvec->page[0].idx != INVALID_INDEX); + sp = pvec->page[0].sp; level = sp->role.level; WARN_ON(level == PT_PAGE_TABLE_LEVEL); @@ -2020,6 +2024,7 @@ static void mmu_pages_clear_parents(struct mmu_page_path *parents) if (!sp) return; + WARN_ON(idx == INVALID_INDEX); clear_unsync_child_bit(sp, idx); level++; } while (!sp->unsync_children); -- 1.8.3.1