From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 330E3C433EF for ; Fri, 13 May 2022 23:10:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230304AbiEMXKZ (ORCPT ); Fri, 13 May 2022 19:10:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54390 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229521AbiEMXKX (ORCPT ); Fri, 13 May 2022 19:10:23 -0400 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 11A0C2E1DD8 for ; Fri, 13 May 2022 16:10:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1652483404; x=1684019404; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=AmRezgHHEdw2JBZ1v9lIr+kT3Im+6xmk5HtIS/CA1Mc=; b=mq88SsGHEiytXQZkzQYrghDeb1U2DCPBtTrIHjA0IfAJXpW9ZyV+T3J+ Jg+2gVpLjkUNPAXVqddnZdgQDD7uDbIXjBtaxDO+1Acf9g8tPrnauULDE vdmfyEE+zN3Id4+pg+/1ixc/w0QMnbuTsFlW7uIO4lGyC1KFnNleBR5QX H2OTXkGABpeYWZDSrrwGp4lnQCLKztXC8IrKJHbvUoWtpZuX7WfocswUY bXxCi4J1TqaU8vQrHLmL4MpbQkW1IbZtA4r0EO7ogc9svDSLxfnjWddcE 83VCuhr+vSSqK3zUhUDT18MP3SwpMrKYMVsMaCsmEd0cDTx+BmQKvdQN8 Q==; X-IronPort-AV: E=McAfee;i="6400,9594,10346"; a="268021474" X-IronPort-AV: E=Sophos;i="5.91,223,1647327600"; d="scan'208";a="268021474" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 May 2022 16:10:03 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.91,223,1647327600"; d="scan'208";a="740373181" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga005.jf.intel.com with ESMTP; 13 May 2022 16:10:00 -0700 Received: by black.fi.intel.com (Postfix, from userid 1000) id 08838A8; Sat, 14 May 2022 02:09:58 +0300 (EEST) Date: Sat, 14 May 2022 02:09:58 +0300 From: "Kirill A. Shutemov" To: "Edgecombe, Rick P" Cc: "glider@google.com" , "linux-kernel@vger.kernel.org" , "peterz@infradead.org" , "hjl.tools@gmail.com" , "linux-mm@kvack.org" , "dave.hansen@linux.intel.com" , "aryabinin@virtuozzo.com" , "dvyukov@google.com" , "x86@kernel.org" , "ak@linux.intel.com" , "Lutomirski, Andy" Subject: Re: [RFCv2 03/10] x86: Introduce userspace API to handle per-thread features Message-ID: <20220513230958.dbxp6m3y3lnq74qb@black.fi.intel.com> References: <20220511022751.65540-1-kirill.shutemov@linux.intel.com> <20220511022751.65540-5-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 13, 2022 at 05:34:12PM +0000, Edgecombe, Rick P wrote: > On Fri, 2022-05-13 at 16:09 +0200, Alexander Potapenko wrote: > > > + > > > + /* Handle ARCH_THREAD_FEATURE_ENABLE */ > > > + > > > + task->thread.features |= features; > > > +out: > > > + return task->thread.features; > > > > Isn't arch_prctl() supposed to return 0 on success? > > Hmm, good point. Maybe we'll need a struct to pass info in and out. But values >0 are unused. I don't see why can't we use them. -- Kirill A. Shutemov