From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@bugzilla.kernel.org Subject: [Bug 63131] guest hang when reboot . Date: Wed, 16 Oct 2013 02:16:24 +0000 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit To: kvm@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.19.201]:43281 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754581Ab3JPCQ1 (ORCPT ); Tue, 15 Oct 2013 22:16:27 -0400 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 052E42044B for ; Wed, 16 Oct 2013 02:16:27 +0000 (UTC) Received: from bugzilla2.web.kernel.org (bugzilla2.web.kernel.org [172.20.200.52]) by mail.kernel.org (Postfix) with ESMTP id 4AF7620426 for ; Wed, 16 Oct 2013 02:16:25 +0000 (UTC) In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: https://bugzilla.kernel.org/show_bug.cgi?id=63131 --- Comment #1 from Zhou, Chao --- the first bad commit is commit d7876f1be40a16223a44355740de625849504eb5 Author: Paolo Bonzini Date: Wed Oct 2 16:06:15 2013 +0200 KVM: x86: prevent setting unsupported XSAVE states A guest can still attempt to save and restore XSAVE states even if they have been masked in CPUID leaf 0Dh. This usually is not visible to the guest, but is still wrong: "Any attempt to set a reserved bit (as determined by the contents of EAX and EDX after executing CPUID with EAX=0DH, ECX= 0H) in XCR0 for a given processor will result in a #GP exception". The patch also performs the same checks as __kvm_set_xcr in KVM_SET_XSAVE. This catches migration from newer to older kernel/processor before the guest starts running. Signed-off-by: Paolo Bonzini Signed-off-by: Gleb Natapov -- You are receiving this mail because: You are watching the assignee of the bug.