From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DA547C432C3 for ; Fri, 15 Nov 2019 06:22:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B27FD2053B for ; Fri, 15 Nov 2019 06:22:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573798953; bh=7Xw0QoSwiCAilYPRBt1bdNY9DKHi7cJfewbH0qGOk2o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Rpg3+d2L7nmBqDpmGCg637m7TDjmSglgBiXlfJhqIpJhuWr0c8c2R+zHynsPvEJZ5 zdATa4t9K2iaU3NR8vitmlSI3CI2wZtK8DTJNdiVSKPsrEuDmjStQzGRZs/41dW4hP JsSaWujTCWwRAO2GeDEgeYAWvSvOB+orhKee4s/4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727745AbfKOGWb (ORCPT ); Fri, 15 Nov 2019 01:22:31 -0500 Received: from mail.kernel.org ([198.145.29.99]:51784 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727711AbfKOGWZ (ORCPT ); Fri, 15 Nov 2019 01:22:25 -0500 Received: from localhost (unknown [104.132.150.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CB2AD2053B; Fri, 15 Nov 2019 06:22:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573798945; bh=7Xw0QoSwiCAilYPRBt1bdNY9DKHi7cJfewbH0qGOk2o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pse1r60oV4VI0W5N7h0pyHxWO30vZOhORIx4/HTaYuLDxwjdACDG7OY00UBeM58Qt JqqGP0+PFrjxw3u9yrveFTN5B0aIcr9KwKDEQB9KRj/5p7CQYFzT2Sd8AkHQejGAU5 04gLBwIE0OXr8g3cw4N48ofHZAVnmGyTiGSSikkE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Paolo Bonzini , Ben Hutchings Subject: [PATCH 4.9 22/31] KVM: x86: change kvm_mmu_page_get_gfn BUG_ON to WARN_ON Date: Fri, 15 Nov 2019 14:20:51 +0800 Message-Id: <20191115062018.282579382@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191115062009.813108457@linuxfoundation.org> References: <20191115062009.813108457@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Paolo Bonzini commit e9f2a760b158551bfbef6db31d2cae45ab8072e5 upstream. Note that in such a case it is quite likely that KVM will BUG_ON in __pte_list_remove when the VM is closed. However, there is no immediate risk of memory corruption in the host so a WARN_ON is enough and it lets you gather traces for debugging. Signed-off-by: Paolo Bonzini Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/mmu.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -781,10 +781,16 @@ static gfn_t kvm_mmu_page_get_gfn(struct static void kvm_mmu_page_set_gfn(struct kvm_mmu_page *sp, int index, gfn_t gfn) { - if (sp->role.direct) - BUG_ON(gfn != kvm_mmu_page_get_gfn(sp, index)); - else + if (!sp->role.direct) { sp->gfns[index] = gfn; + return; + } + + if (WARN_ON(gfn != kvm_mmu_page_get_gfn(sp, index))) + pr_err_ratelimited("gfn mismatch under direct page %llx " + "(expected %llx, got %llx)\n", + sp->gfn, + kvm_mmu_page_get_gfn(sp, index), gfn); } /*