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[23.128.96.18]) by mx.google.com with ESMTP id m6si9157462ejl.605.2021.02.19.14.01.26; Fri, 19 Feb 2021 14:01:58 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=MUiYkHmd; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230042AbhBSWAb (ORCPT + 99 others); Fri, 19 Feb 2021 17:00:31 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:32733 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230020AbhBSV5E (ORCPT ); Fri, 19 Feb 2021 16:57:04 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1613771738; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=KVG0whDdlMFBJekRHUR7N55fu1AUMWMhyCg/ZyhU7g8=; b=MUiYkHmdRTd5CQ0xwZe2jk54pu0NyJbWMBDPJHM5lTJg2bg30iE5vmNCNm03Z+QUrY0eet OcjYy0RCO1E2a7S2eZTFKXrO4ACMjbdbYHfv3Ej6LhPeHH38scOx6PNENByzU2DsAwOhqm MHGRWGJOWD1THdXt4w5PayjtTypq5Pk= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-483-tvU_WTcTNyq2-_WMheOehg-1; Fri, 19 Feb 2021 16:55:36 -0500 X-MC-Unique: tvU_WTcTNyq2-_WMheOehg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7DB7F1020C22; Fri, 19 Feb 2021 21:55:34 +0000 (UTC) Received: from treble (ovpn-115-143.rdu2.redhat.com [10.10.115.143]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 792131971E; Fri, 19 Feb 2021 21:55:32 +0000 (UTC) Date: Fri, 19 Feb 2021 15:55:30 -0600 From: Josh Poimboeuf To: Peter Zijlstra Cc: x86@kernel.org, pjt@google.com, mbenes@suze.cz, jgross@suse.com, linux-kernel@vger.kernel.org Subject: Re: [RFC][PATCH 6/6] objtool,x86: Rewrite retpoline thunk calls Message-ID: <20210219215530.ivzzv3oavhuip6un@treble> References: <20210219204300.749932493@infradead.org> <20210219210535.492733466@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20210219210535.492733466@infradead.org> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 19, 2021 at 09:43:06PM +0100, Peter Zijlstra wrote: > Arguably it would be simpler to do the other way around, but > unfortunately alternatives don't work that way, we cannot say: > > ALTERNATIVE "call __x86_indirect_thunk_\reg", > "call *%reg", ~X86_FEATURE_RETPOLINE > > That is, there is no negative form of alternatives. X86_FEATURE_NO_RETPOLINE? -- Josh