From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf1-x12f.google.com (mail-lf1-x12f.google.com [IPv6:2a00:1450:4864:20::12f]) by sourceware.org (Postfix) with ESMTPS id 9AC743857C59 for ; Sun, 7 Feb 2021 14:09:09 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 9AC743857C59 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=shutemov.name Authentication-Results: sourceware.org; spf=none smtp.mailfrom=kirill@shutemov.name Received: by mail-lf1-x12f.google.com with SMTP id a8so18078372lfi.8 for ; Sun, 07 Feb 2021 06:09:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=shutemov-name.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=3WGdnPvISs64NeCdwfew7cl4A+lVQsglEqZAL7qKKck=; b=N/K1mbr7vtBj7ZjjCa7b5P7eXXnKKs+HjGZDu4xkzSHwBTzUxYIArRUoIfj+qxNdnS w6UmMXkFIKBjjMXa+5VXwOUC/34D20hKZ5bU3LJ/LEjPvNb5u2xHSEDIpn4JMM18xMlj 0BIrrEHC5Z7wABsWF+dA38XofrThWLr1vNnRIt8hkMUBBblLJczgMhill0T9OkJP5O7v d3e1XrIB7QPCTUEQ+P701I818w8qgbH2g4m/7NTOdmUURU62qnYfoDi9UU+LXtyZjR2I e+H38//N/BO2Qnfq6Bh7u/cQFT10O2UtA87NHF2z98qQmainwT9MHa+7pt0RwNIsZJgc Dgaw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=3WGdnPvISs64NeCdwfew7cl4A+lVQsglEqZAL7qKKck=; b=FceB1H6jrtNcZZJsjZzf4Zbc/eAUdcKa7pPjaC2tADEpfck/FXYVVNWTdrRpUbiJON CQJbDwVixXjV9XNw9cGfzgewZkt0cCNNaTmGb+8/dX1lxgQjocaGE37JiYKPdEfNPJLk M56x74xxEgHFHzOYEJMhDGjMGdMeH8ROKjfWyK1DBaCP+z+0UO2wgPK3vaaa9wWxt023 fyN4zm4j66BcJUsft0Dy2ErUd+ra70/9QokXgls8wKl2P+yVCJeO5GnB41nb+jYddCUb jFVKr7Sm+u3qORI2KRNuxGt4eF3H4qw0t6SEftUVtZaAXzPQ4OUe0ZUCCj7Q2XpMyYhc qHuQ== X-Gm-Message-State: AOAM530ztmKYGOcsec/xKy1nyhsXv4NULzYY0sLwsX41WPDWToCQR92l PD6udi5uLZnNjmz1IbrRg8dQtA== X-Google-Smtp-Source: ABdhPJwXp/oy+V9Wswzmu/s94NDp417EvomnDa9nyhb8+7f+CoIzFtqIvBCuwa0s2sOkvmdAbytoaA== X-Received: by 2002:a19:ac08:: with SMTP id g8mr319535lfc.428.1612706947859; Sun, 07 Feb 2021 06:09:07 -0800 (PST) Received: from box.localdomain ([86.57.175.117]) by smtp.gmail.com with ESMTPSA id d15sm1705266lfm.183.2021.02.07.06.09.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 07 Feb 2021 06:09:07 -0800 (PST) Received: by box.localdomain (Postfix, from userid 1000) id A6568102656; Sun, 7 Feb 2021 17:09:06 +0300 (+03) Date: Sun, 7 Feb 2021 17:09:06 +0300 From: "Kirill A. Shutemov" To: Dmitry Vyukov Cc: "H.J. Lu" , "Kirill A. Shutemov" , Dave Hansen , Andy Lutomirski , Peter Zijlstra , the arch/x86 maintainers , Andrey Ryabinin , Alexander Potapenko , Catalin Marinas , Will Deacon , Andi Kleen , Linux-MM , LKML , GNU C Library , GCC Development Subject: Re: [RFC 9/9] x86/mm: Implement PR_SET/GET_TAGGED_ADDR_CTRL with LAM Message-ID: <20210207140906.hdfzorevpmiqtryd@box> References: <20210205151631.43511-1-kirill.shutemov@linux.intel.com> <20210205151631.43511-11-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Spam-Status: No, score=0.7 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, RCVD_IN_BARRACUDACENTRAL, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=no autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gcc@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 07 Feb 2021 14:09:11 -0000 On Sun, Feb 07, 2021 at 09:07:02AM +0100, Dmitry Vyukov wrote: > On Fri, Feb 5, 2021 at 4:43 PM H.J. Lu wrote: > > > > On Fri, Feb 5, 2021 at 7:16 AM Kirill A. Shutemov > > wrote: > > > > > > Provide prctl() interface to enabled LAM for user addresses. Depending > > > how many tag bits requested it may result in enabling LAM_U57 or > > > LAM_U48. > > > > I prefer the alternate kernel interface based on CET arch_prctl interface which > > is implemented in glibc on users/intel/lam/master branch: > > > > https://gitlab.com/x86-glibc/glibc/-/tree/users/intel/lam/master > > > > and in GCC on users/intel/lam/master branch: > > > > https://gitlab.com/x86-gcc/gcc/-/tree/users/intel/lam/master > > Hi Kirill, H.J., > > I don't have strong preference for PR_SET/GET_TAGGED_ADDR_CTRL vs > ARCH_X86_FEATURE_1_ENABLE itself, but tying LAM to ELF and > GNU_PROPERTY in the second option looks strange. LAM can be used > outside of ELF/GNU, right? Sure. In both cases it's still a syscall. -- Kirill A. Shutemov