From owner-freebsd-bugs@freebsd.org Fri Apr 14 16:54:52 2017 Return-Path: Delivered-To: freebsd-bugs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id CE888D3E9A7 for ; Fri, 14 Apr 2017 16:54:52 +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 mx1.freebsd.org (Postfix) with ESMTPS id A5E07860 for ; Fri, 14 Apr 2017 16:54:52 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id v3EGsqB3054322 for ; Fri, 14 Apr 2017 16:54:52 GMT (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 218662] bhyve exposes CPU feature SDBG to guests, causing guest panic on OpenBSD 6.1 Date: Fri, 14 Apr 2017 16:54:52 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: bin X-Bugzilla-Version: 10.3-RELEASE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: todd.mortimer@gmail.com X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-bugs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter Message-ID: 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-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 14 Apr 2017 16:54:52 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D218662 Bug ID: 218662 Summary: bhyve exposes CPU feature SDBG to guests, causing guest panic on OpenBSD 6.1 Product: Base System Version: 10.3-RELEASE Hardware: amd64 OS: Any Status: New Severity: Affects Some People Priority: --- Component: bin Assignee: freebsd-bugs@FreeBSD.org Reporter: todd.mortimer@gmail.com When attempting to create an OpenBSD 6.1 bhyve guest on 10.3-RELEASE-p18, t= he guest panics early in the boot process when attempting to disable the Silic= on Debug feature identified by CPU feature bit SDBG. This feature bit is passe= d to guests if present on the host CPU.=20 In my case, my CPU is this: CPU: Intel(R) Core(TM) i7-4790S CPU @ 3.20GHz (3192.68-MHz K8-class CPU) Origin=3D"GenuineIntel" Id=3D0x306c3 Family=3D0x6 Model=3D0x3c Steppi= ng=3D3 =20 Features=3D0xbfebfbff =20 Features2=3D0x7ffafbff AMD Features=3D0x2c100800 AMD Features2=3D0x21 Structured Extended Features=3D0x27ab XSAVE Features=3D0x1 VT-x: PAT,HLT,MTF,PAUSE,EPT,UG,VPID TSC: P-state invariant, performance statistics When OpenBSD 6.1 boots under byhve, it detects the SDBG feature and attempt= s to disable it, resulting in a protection fault / panic. This was discussed on the OpenBSD misc list: http://marc.info/?l=3Dopenbsd-misc&m=3D149136052120277&w=3D4 And a patch for HardenedBSD is here: https://github.com/HardenedBSD/hardenedBSD/commit/cc91b57f4d1dabddfbf8b1e76= 55 As a workaround, passing -w to byhve allows the guest to boot, but the CPU feature should be masked out by the host. --=20 You are receiving this mail because: You are the assignee for the bug.=