From owner-freebsd-virtualization@freebsd.org Sun Nov 18 01:08:13 2018 Return-Path: Delivered-To: freebsd-virtualization@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id E23D2110E6E2 for ; Sun, 18 Nov 2018 01:08:12 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mailman.ysv.freebsd.org (mailman.ysv.freebsd.org [IPv6:2001:1900:2254:206a::50:5]) by mx1.freebsd.org (Postfix) with ESMTP id 7794F8A8AE for ; Sun, 18 Nov 2018 01:08:12 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.ysv.freebsd.org (Postfix) id 3B75B110E6DC; Sun, 18 Nov 2018 01:08:12 +0000 (UTC) Delivered-To: virtualization@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 19A5A110E6DB for ; Sun, 18 Nov 2018 01:08:12 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.ysv.freebsd.org (mxrelay.ysv.freebsd.org [IPv6:2001:1900:2254:206a::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (Client CN "mxrelay.ysv.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id ABA908A8A7 for ; Sun, 18 Nov 2018 01:08:11 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.ysv.freebsd.org (Postfix) with ESMTPS id F13191ACBF for ; Sun, 18 Nov 2018 01:08:10 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id wAI18Af8023252 for ; Sun, 18 Nov 2018 01:08:10 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from bugzilla@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id wAI18AWS023251 for virtualization@FreeBSD.org; Sun, 18 Nov 2018 01:08:10 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: bugzilla set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: virtualization@FreeBSD.org Subject: [Bug 230773] [bhyve] GDT limit needs reset on VMX exit Date: Sun, 18 Nov 2018 01:08:11 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: commit-hook@freebsd.org X-Bugzilla-Status: In Progress X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: virtualization@FreeBSD.org X-Bugzilla-Flags: mfc-stable10? mfc-stable11? X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-Rspamd-Queue-Id: 7794F8A8AE X-Spamd-Result: default: False [-0.38 / 15.00]; local_wl_from(0.00)[freebsd.org]; NEURAL_HAM_SHORT(-0.38)[-0.375,0]; ASN(0.00)[asn:10310, ipnet:2001:1900:2254::/48, country:US] X-Rspamd-Server: mx1.freebsd.org X-BeenThere: freebsd-virtualization@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Discussion of various virtualization techniques FreeBSD supports." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 18 Nov 2018 01:08:13 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D230773 --- Comment #6 from commit-hook@freebsd.org --- A commit references this bug: Author: jhb Date: Sun Nov 18 01:07:37 UTC 2018 New revision: 340545 URL: https://svnweb.freebsd.org/changeset/base/340545 Log: MFC 339312,339364: Restore more descriptors during VM exits. 339312: Fully restore the GDTR, IDTR, and LDTR after VT-x VM exits. The VT-x VMCS only stores the base address of the GDTR and IDTR. As a result, VM exits use a fixed limit of 0xffff for the host GDTR and IDTR losing the smaller limits set in when the initial GDT is loaded on each CPU during boot. Explicitly save and restore the full GDTR and IDTR contents around VM entries and exits to restore the correct limit. Similarly, explicitly save and restore the LDT selector. VM exits always clear the host LDTR as if the LDT was loaded with a NULL selector and a userspace hypervisor is probably using a NULL selector anyway, but save and restore the LDT explicitly just to be safe. 339364: Reload the LDT selector after an AMD-v #VMEXIT. cpu_switch() always reloads the LDT, so this can only affect the hypervisor process itself. Fix this by explicitly reloading the host LDT selector after each #VMEXIT. The stock bhyve process on FreeBSD never uses a custom LDT, so this change is cosmetic. PR: 230773 Changes: _U stable/11/ stable/11/sys/amd64/include/cpufunc.h stable/11/sys/amd64/vmm/amd/svm.c stable/11/sys/amd64/vmm/intel/vmx.c --=20 You are receiving this mail because: You are the assignee for the bug.=