Received: by 2002:a05:6902:102b:0:0:0:0 with SMTP id x11csp1498158ybt; Thu, 2 Jul 2020 07:02:48 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwWm2MSWi8qRMjTwMPdiWiLXwVU4KyiQx7h4SN6ioRNInbA1XV9/03uHVxX+AGxg2i+eytv X-Received: by 2002:a17:906:b0d3:: with SMTP id bk19mr29553615ejb.167.1593698568221; Thu, 02 Jul 2020 07:02:48 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1593698568; cv=none; d=google.com; s=arc-20160816; b=JyJhLo0G//RFyfU5B1bw3R1IPgVY/GUQ2CIstxpbpvEZpnPB/dYorIgdqjSQJ4LpRe Frp22gjFbYU4DO3vDYv0Bak5fuv5xxFkd7hUwhhUm3lCz70lLN/6ffFiuuvcNrsyYdn4 +SFRnBXJJhv+ZTLPaOHcGzqBCZmLpxDNWoCkeJfiTAT4jT/uq8gwx4ERhOe4WSzSgL6w gsBHjivGtE2MD3Sio5vb/CxNus/eNw2M1zSKr3gNBpB+dKivU4D89qWjstZzH3FR9/Kr rBzG4/wxzZlOVYAs62d0w6Faad899RWmu8JqIeIYQ9sBC3IM8+/T81D8WbQ9nj1rZbZ4 8WfQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:in-reply-to:content-disposition :mime-version:references:message-id:subject:cc:to:from:date; bh=Ad4Nj6PvrxeFImY7ofxBpVDvrqloSIyeQ/qUvtz7lLg=; b=T6atIXLeWgHSgIm3mvt5rgSasmQnl0hAtWLZoOGMn/KdR6wHRwbROnJDDguKRTVBO8 sNVEQxFNQXohhfSpUXiDTDC3L8vLlZKSXdcgYOsNhx1K14n6ru6KO9MrcyBJIECZ4m1f uEM7KbZ7McWofhQlCcLEBuczA0X8ti4kGIyH0VYTorTtuJTJ1v2eKvNf/PcbNrTY21aJ 1AJf386m+A+APPyruTy0pBsc6LNYnSkx471xfxhPywqIqroFK8oTo0FwXJ9H+e4JfzWT dzbwEdhZoNJEsDKf6N9Z+U7ckyFWlvqgug4RwUmjz3Tj5ZEZPdAPzQf4cK/L/B2q4gYa TviA== ARC-Authentication-Results: i=1; mx.google.com; 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 Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id t10si5919706ejs.137.2020.07.02.07.02.22; Thu, 02 Jul 2020 07:02:48 -0700 (PDT) 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; 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 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729388AbgGBOCQ (ORCPT + 99 others); Thu, 2 Jul 2020 10:02:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43252 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726343AbgGBOCQ (ORCPT ); Thu, 2 Jul 2020 10:02:16 -0400 Received: from ZenIV.linux.org.uk (zeniv.linux.org.uk [IPv6:2002:c35c:fd02::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5A710C08C5C1 for ; Thu, 2 Jul 2020 07:02:16 -0700 (PDT) Received: from viro by ZenIV.linux.org.uk with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jqzmp-003yXo-RX; Thu, 02 Jul 2020 14:01:59 +0000 Date: Thu, 2 Jul 2020 15:01:59 +0100 From: Al Viro To: Michael Ellerman Cc: Linus Torvalds , Christophe Leroy , Josh Poimboeuf , Peter Zijlstra , the arch/x86 maintainers , Linux Kernel Mailing List Subject: Re: objtool clac/stac handling change.. Message-ID: <20200702140159.GM2786714@ZenIV.linux.org.uk> References: <20200701184131.GI2786714@ZenIV.linux.org.uk> <20200701195914.GK2786714@ZenIV.linux.org.uk> <87lfk26nx4.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87lfk26nx4.fsf@mpe.ellerman.id.au> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 02, 2020 at 11:34:31PM +1000, Michael Ellerman wrote: > I think we can do something to make it work. > > We don't have an equivalent of x86's ex_handler_uaccess(), so it's not > quite as easy as whacking a user_access_end() in there. > > Probably the simplest option for us is to just handle it in our > unsafe_op_wrap(). I'll try and come up with something tomorrow. The goal is to avoid using unsafe_op_wrap()...