From patchwork Thu Sep 15 21:51:08 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: James Hogan X-Patchwork-Id: 9334761 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 5DF6560839 for ; Thu, 15 Sep 2016 21:51:31 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 48A7A29C3F for ; Thu, 15 Sep 2016 21:51:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3D68229C46; Thu, 15 Sep 2016 21:51:31 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7D46729C3F for ; Thu, 15 Sep 2016 21:51:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754243AbcIOVv0 (ORCPT ); Thu, 15 Sep 2016 17:51:26 -0400 Received: from mailapp01.imgtec.com ([195.59.15.196]:41175 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751968AbcIOVv0 (ORCPT ); Thu, 15 Sep 2016 17:51:26 -0400 Received: from HHMAIL01.hh.imgtec.org (unknown [10.100.10.19]) by Forcepoint Email with ESMTPS id 94AF1210FA4EF; Thu, 15 Sep 2016 22:51:09 +0100 (IST) Received: from jhogan-linux.le.imgtec.org (192.168.154.110) by HHMAIL01.hh.imgtec.org (10.100.10.21) with Microsoft SMTP Server (TLS) id 14.3.294.0; Thu, 15 Sep 2016 22:51:13 +0100 From: James Hogan To: CC: James Hogan , Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Ralf Baechle , , Subject: [PATCH BACKPORT 3.17-4.7] MIPS: KVM: Check for pfn noslot case Date: Thu, 15 Sep 2016 22:51:08 +0100 Message-ID: <947668829a347e094a2b1e4af7792857d0960a6b.1473976044.git-series.james.hogan@imgtec.com> X-Mailer: git-send-email 2.7.3 MIME-Version: 1.0 X-Originating-IP: [192.168.154.110] Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP commit ba913e4f72fc9cfd03dad968dfb110eb49211d80 upstream. When mapping a page into the guest we error check using is_error_pfn(), however this doesn't detect a value of KVM_PFN_NOSLOT, indicating an error HVA for the page. This can only happen on MIPS right now due to unusual memslot management (e.g. being moved / removed / resized), or with an Enhanced Virtual Memory (EVA) configuration where the default KVM_HVA_ERR_* and kvm_is_error_hva() definitions are unsuitable (fixed in a later patch). This case will be treated as a pfn of zero, mapping the first page of physical memory into the guest. It would appear the MIPS KVM port wasn't updated prior to being merged (in v3.10) to take commit 81c52c56e2b4 ("KVM: do not treat noslot pfn as a error pfn") into account (merged v3.8), which converted a bunch of is_error_pfn() calls to is_error_noslot_pfn(). Switch to using is_error_noslot_pfn() instead to catch this case properly. Fixes: 858dd5d45733 ("KVM/MIPS32: MMU/TLB operations for the Guest.") Signed-off-by: James Hogan Cc: Paolo Bonzini Cc: "Radim Krčmář" Cc: Ralf Baechle Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Signed-off-by: Paolo Bonzini [james.hogan@imgtec.com: Backport to v4.7.y] Signed-off-by: James Hogan --- arch/mips/kvm/tlb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/mips/kvm/tlb.c b/arch/mips/kvm/tlb.c index ed021ae7867a..4e0a8f23af78 100644 --- a/arch/mips/kvm/tlb.c +++ b/arch/mips/kvm/tlb.c @@ -159,7 +159,7 @@ static int kvm_mips_map_page(struct kvm *kvm, gfn_t gfn) srcu_idx = srcu_read_lock(&kvm->srcu); pfn = kvm_mips_gfn_to_pfn(kvm, gfn); - if (kvm_mips_is_error_pfn(pfn)) { + if (is_error_noslot_pfn(pfn)) { kvm_err("Couldn't get pfn for gfn %#" PRIx64 "!\n", gfn); err = -EFAULT; goto out;