From patchwork Thu Jun 9 09:50:44 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: James Hogan X-Patchwork-Id: 9166627 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 53B4B6048F for ; Thu, 9 Jun 2016 09:51:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 43C9B2830C for ; Thu, 9 Jun 2016 09:51:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 38DFE28336; Thu, 9 Jun 2016 09:51:29 +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 E01702830C for ; Thu, 9 Jun 2016 09:51:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753951AbcFIJvK (ORCPT ); Thu, 9 Jun 2016 05:51:10 -0400 Received: from mailapp01.imgtec.com ([195.59.15.196]:12693 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753717AbcFIJvG (ORCPT ); Thu, 9 Jun 2016 05:51:06 -0400 Received: from HHMAIL01.hh.imgtec.org (unknown [10.100.10.19]) by Forcepoint Email with ESMTPS id D0F7A9A4B598D; Thu, 9 Jun 2016 10:51:01 +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, 9 Jun 2016 10:51:04 +0100 From: James Hogan To: Paolo Bonzini CC: James Hogan , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Ralf Baechle , , Subject: [PATCH 2/4] MIPS: KVM: Include bit 31 in segment matches Date: Thu, 9 Jun 2016 10:50:44 +0100 Message-ID: <1465465846-31918-3-git-send-email-james.hogan@imgtec.com> X-Mailer: git-send-email 2.4.10 In-Reply-To: <1465465846-31918-1-git-send-email-james.hogan@imgtec.com> References: <1465465846-31918-1-git-send-email-james.hogan@imgtec.com> 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 When faulting guest addresses are matched against guest segments with the KVM_GUEST_KSEGX() macro, change the mask to 0xe0000000 so as to include bit 31. This is mainly for safety's sake, as it prevents a rogue BadVAddr in the host kseg2/kseg3 segments (e.g. 0xC*******) after a TLB exception from matching the guest kseg0 segment (e.g. 0x4*******), triggering an internal KVM error instead of allowing the corresponding guest kseg0 page to be mapped into the host vmalloc space. Such a rogue BadVAddr was observed to happen with the host MIPS kernel running under QEMU with KVM built as a module, due to a not entirely transparent optimisation in the QEMU TLB handling. This has already been worked around properly in a previous commit. Signed-off-by: James Hogan Cc: Paolo Bonzini Cc: Radim Krčmář Cc: Ralf Baechle Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org --- arch/mips/include/asm/kvm_host.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h index 2d5bb133d11a..36a391d289aa 100644 --- a/arch/mips/include/asm/kvm_host.h +++ b/arch/mips/include/asm/kvm_host.h @@ -74,7 +74,7 @@ #define KVM_GUEST_KUSEG 0x00000000UL #define KVM_GUEST_KSEG0 0x40000000UL #define KVM_GUEST_KSEG23 0x60000000UL -#define KVM_GUEST_KSEGX(a) ((_ACAST32_(a)) & 0x60000000) +#define KVM_GUEST_KSEGX(a) ((_ACAST32_(a)) & 0xe0000000) #define KVM_GUEST_CPHYSADDR(a) ((_ACAST32_(a)) & 0x1fffffff) #define KVM_GUEST_CKSEG0ADDR(a) (KVM_GUEST_CPHYSADDR(a) | KVM_GUEST_KSEG0)