From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758853AbcGKNTM (ORCPT ); Mon, 11 Jul 2016 09:19:12 -0400 Received: from mga04.intel.com ([192.55.52.120]:2997 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753856AbcGKNR4 (ORCPT ); Mon, 11 Jul 2016 09:17:56 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.28,346,1464678000"; d="scan'208";a="1019448930" From: "Fenghua Yu" To: "Ingo Molnar" , "Thomas Gleixner" , "H. Peter Anvin" , "Dave Hansen" , "Ravi V Shankar" Cc: Yu-cheng Yu , "Fenghua Yu" , "x86" , "linux-kernel" Subject: [PATCH 2/4] x86/fpu/xstate: Return NULL for disabled xstate component address Date: Mon, 11 Jul 2016 09:18:55 -0700 Message-Id: <1468253937-40008-3-git-send-email-fenghua.yu@intel.com> X-Mailer: git-send-email 1.8.0.1 In-Reply-To: <1468253937-40008-1-git-send-email-fenghua.yu@intel.com> References: <1468253937-40008-1-git-send-email-fenghua.yu@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yu-cheng Yu It is an error to request a disabled XSAVE/XSAVES component address. For that case, make __raw_xsave_addr() return a NULL and issue a warning. Signed-off-by: Yu-cheng Yu Signed-off-by: Fenghua Yu Reviewed-by: Dave Hansen --- arch/x86/kernel/fpu/xstate.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index f8d1aff..4fb8dd7 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -760,6 +760,11 @@ void *__raw_xsave_addr(struct xregs_state *xsave, int xstate_feature_mask) { int feature_nr = fls64(xstate_feature_mask) - 1; + if (!xfeature_enabled(feature_nr)) { + WARN_ON_FPU(1); + return NULL; + } + return (void *)xsave + xstate_comp_offsets[feature_nr]; } /* -- 2.5.0