Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752628AbaKLNiw (ORCPT ); Wed, 12 Nov 2014 08:38:52 -0500 Received: from mga14.intel.com ([192.55.52.115]:43371 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752307AbaKLNis convert rfc822-to-8bit (ORCPT ); Wed, 12 Nov 2014 08:38:48 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,862,1389772800"; d="scan'208";a="415391634" From: "Anvin, H Peter" To: Borislav Petkov , Ross Zwisler CC: "linux-kernel@vger.kernel.org" , Ingo Molnar , Thomas Gleixner , David Airlie , "dri-devel@lists.freedesktop.org" , "x86@kernel.org" Subject: RE: [PATCH 3/6] x86: Add support for the clwb instruction Thread-Topic: [PATCH 3/6] x86: Add support for the clwb instruction Thread-Index: AQHP/d90ErPA0vQakUG7oLRaEWzcKpxddayA//+KiqE= Date: Wed, 12 Nov 2014 13:38:45 +0000 Message-ID: References: <1415731396-19364-1-git-send-email-ross.zwisler@linux.intel.com> <1415731396-19364-4-git-send-email-ross.zwisler@linux.intel.com>,<20141112123909.GD16807@pd.tnic> In-Reply-To: <20141112123909.GD16807@pd.tnic> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.4.15.193] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org No, it doesn't. x86 requires 3.4+ at a minimum. ________________________________ From: Borislav Petkov Sent: Wednesday, November 12, 2014 4:39:09 AM To: Ross Zwisler Cc: linux-kernel@vger.kernel.org; Anvin, H Peter; Ingo Molnar; Thomas Gleixner; David Airlie; dri-devel@lists.freedesktop.org; x86@kernel.org Subject: Re: [PATCH 3/6] x86: Add support for the clwb instruction On Tue, Nov 11, 2014 at 11:43:13AM -0700, Ross Zwisler wrote: > +static inline void clwb(volatile void *__p) > +{ > + alternative_io_2(".byte " __stringify(NOP_DS_PREFIX) "; clflush %P0", > + ".byte 0x66; clflush %P0", > + X86_FEATURE_CLFLUSHOPT, > + ".byte 0x66; xsaveopt %P0", Btw, I'm afraid you're going to have to spell out those new instruction mnemonics as they aren't supported by older compilers: CC drivers/gpu/drm/drm_cache.o {standard input}: Assembler messages: {standard input}:63: Error: no such instruction: `xsaveopt (%rax)' {standard input}:249: Error: no such instruction: `xsaveopt (%rdi)' {standard input}:283: Error: no such instruction: `xsaveopt -1(%rdx)' make[1]: *** [drivers/gpu/drm/drm_cache.o] Error 1 make: *** [drivers/gpu/drm/drm_cache.o] Error 2 [boris@etch:14:35:40:k:14)-> gcc --version gcc (GCC) 4.1.2 20061115 (prerelease) (Debian 4.1.1-21) This is on a very old guest I have which has this gcc in it and the kernel supports everything gcc >= 3.2. -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/