From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f68.google.com (mail-wr1-f68.google.com [209.85.221.68]) by mx.groups.io with SMTP id smtpd.web11.5612.1590067008033780258 for ; Thu, 21 May 2020 06:16:48 -0700 Authentication-Results: mx.groups.io; dkim=pass header.i=@nuviainc-com.20150623.gappssmtp.com header.s=20150623 header.b=CcWxZHnS; spf=pass (domain: nuviainc.com, ip: 209.85.221.68, mailfrom: leif@nuviainc.com) Received: by mail-wr1-f68.google.com with SMTP id r3so4720983wrn.11 for ; Thu, 21 May 2020 06:16:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nuviainc-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=fpcOiDx/gQxATJcMXU9NExjEAcfY/8i9j35goY6Jibs=; b=CcWxZHnSuQQaLZ5TfyT55m7UG0E3dK0iPnYltiTo3wBsv9di09OEn1LxO0cVW1EQTh WdxIo/9k6Hl39CX8SJVoQBT+eEtUno955ESBGMz0qYNto+ykYdgpFL5SClcOY72s/5gD eBV0hGgpruj2mw51s7HjYXHtj8xdxPgyYqv7RbBt0BNS3+lzJ4+ovoz/k9H040Z/ryG2 KtgoJC0Ja+zxW4NQCxaLsrG00SEIRZHYaMPrpvdFKEp9IV6e6SizdJ2xBFVsTIum/HAA CxsfmlQ9NLunJu6q13aLNiZYBXwXbWNZJYppT0f8Snr9MQ6zIFyKEKAsZb7MtWq9Nev2 a1FQ== 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:user-agent; bh=fpcOiDx/gQxATJcMXU9NExjEAcfY/8i9j35goY6Jibs=; b=JAHJXaDh9NiAtj2pkAn6vMwOvsgZzL/v/zNGOstQx2J8G0fg/pOytFJRjhCDjDlgV6 Ub3qDYVRI1BSRDOGQ4YtB7WlVzubMD/347EzliImE56O2jc2jy3iM0XHHU3VL6jNBMr6 pp9N2TMdZFheYrm5iZUpT1AfY+PAwYWLh/+a3+7WNQZxmegVw9GJyRCY39i7pTnl2QtJ Z5FtpnUX8A2ka8lXRVP3ZI6sJD827CLElpDTFaNizA3NmwGDxz6DzbZuXKypCkwVLFY+ 9nM1Y6S5f68D5uDbr3RwhBig5Tk25WHr9f4QKodFDwzjizFuAg/Gp4hoBQaalFuGY+e9 599Q== X-Gm-Message-State: AOAM530Pt30/LVmEmcMBBl3FCxSznpnb404rcY21PpiAGwKab7aFGtQ9 X/bqixIPlgBH7eZvP8qTc+pWdg== X-Google-Smtp-Source: ABdhPJwj0U/DS5oA7SeZWRu50JpHHBixayeOqvZoIfwpoO+dctNKLAtfIEDBZGWuFdRnELTWN5jiUw== X-Received: by 2002:a5d:4745:: with SMTP id o5mr9204751wrs.128.1590067006573; Thu, 21 May 2020 06:16:46 -0700 (PDT) Return-Path: Received: from vanye ([2001:470:1f09:12f0:b26e:bfff:fea9:f1b8]) by smtp.gmail.com with ESMTPSA id k131sm6979630wma.2.2020.05.21.06.16.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 May 2020 06:16:46 -0700 (PDT) Date: Thu, 21 May 2020 14:16:44 +0100 From: "Leif Lindholm" To: Ard Biesheuvel Cc: devel@edk2.groups.io, glin@suse.com, lersek@redhat.com, liming.gao@intel.com Subject: Re: [edk2-devel] [PATCH v2] ArmPkg/CompilerIntrinsicsLib: provide atomics intrinsics Message-ID: <20200521131644.GT1923@vanye> References: <20200520114448.26104-1-ard.biesheuvel@arm.com> <20200521112353.GS1923@vanye> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Thu, May 21, 2020 at 14:58:56 +0200, Ard Biesheuvel wrote: > > Reviewed-by: Leif Lindholm > > Thanks! > > > > Apparently, GCC 10 is getting fixed so that we can set a #pragma in > MdePkg/Include/AArch64/ProcessorBind.h, and be done with it. > > That does mean you would need GCC 10.2 at least, or you get the error, > unless we merge this patch as well. That would mean the intrinsics are never > used in practice, but using a compiler that does use them will not break the > build. > > I am leaning towards omitting this patch, but I could be convinced to adopt > both mitigations. But the #pragma is strongly preferred. What is the codesize impact on a full RELEASE image? If non-negligable, how about #ifdefing the whole content out unless some specific preprocessor flag is passed? Then at least there's a quick workaround for anyone who needs it. / Leif