From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <ak@linux.intel.com>
X-Google-Smtp-Source: ACJfBouxuzBZ+fqDs0plpjgNbMzGInEWj4Aej5lrlfF8VwVLhmfQ9wMH10Eo6tYRTa8J3IB5FOaZ
ARC-Seal: i=1; a=rsa-sha256; t=1516280545; cv=none;
        d=google.com; s=arc-20160816;
        b=wv4T6Aq/SRBYTMnsP12q/v/a9lIvrmn3Qh6eq40/k4PxZeFfDEnFW/BPJeA0TE4zf0
         jfkZADZHPXIS1mkMP1OfaJamRmECgJhjaH7AB17/kmzHZKs8n3XOHCSqaHvsVq6muigd
         PK2z7YQgJ2vYjSg+AumBDHijyFKfqIAgvIP7lJhNjwlYNjgl3weYu6PtZsu4955ZFE2s
         jllGGGWNlcKpKtg93xNshJtehHvCjbTdSFyyVdCCJfRZjPnFC2LelfF7oY/nvEjh9ky+
         9x/OyYKwA89gXMT2o/OoJwS7folucyUdoqGdF5RMLAGlZhTmwPbWSl6s55Zuj/grIWCP
         XgBA==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816;
        h=user-agent:in-reply-to:content-disposition:mime-version:references
         :message-id:subject:cc:to:from:date:arc-authentication-results;
        bh=etJA7L6hko+wKhWSfbVQtcwHu04DP6APAHnKEfiAcm4=;
        b=V1sxNZgXOgcoOZHsZp1ZaZagxGfQrVTHnqWtprKrwK5ZhJlT2RQeOt7Q2RVHLBTnMt
         oDWdXDUw7/h33cHZMi5cgqW18AuNFeJ0Gm8tVvug0qAVlB+JJrXUUcx0IspXZqVg0yji
         kv+YJTsc6mLoDAaGCYCenreyoac5eTEKCsTS6iGb7sLVAM5P6R1NG6/zf5Qf/tKfoZAK
         oAFlcriQGRhcBgD7fBw4lxw/LDBgHdYozEFS2QVQV5E7rh1C6huvQN1vNqa24RIHKK6T
         ANS+WiNRcgoLjZ3Eh/DMBPFfVbKjxwUrZGdbdNjxQVo+vNem3BgM4572KAn2IA2JiLkQ
         +GVA==
ARC-Authentication-Results: i=1; mx.google.com;
       spf=pass (google.com: best guess record for domain of ak@linux.intel.com designates 134.134.136.31 as permitted sender) smtp.mailfrom=ak@linux.intel.com
Authentication-Results: mx.google.com;
       spf=pass (google.com: best guess record for domain of ak@linux.intel.com designates 134.134.136.31 as permitted sender) smtp.mailfrom=ak@linux.intel.com
X-Amp-Result: UNSCANNABLE
X-Amp-File-Uploaded: False
X-ExtLoop1: 1
X-IronPort-AV: E=Sophos;i="5.46,377,1511856000";
   d="scan'208";a="20760349"
Date: Thu, 18 Jan 2018 05:01:57 -0800
From: Andi Kleen <ak@linux.intel.com>
To: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>, David Woodhouse <dwmw@amazon.co.uk>,
	linux-kernel@vger.kernel.org,
	Greg Kroah-Hartman <gregkh@linux-foundation.org>,
	Arjan van de Ven <arjan@linux.intel.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	"H . Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH v1 tip/master 0/3] kprobes/x86: retpoline: Fix kprobes
 for retpoline
Message-ID: <20180118130157.GE7844@tassilo.jf.intel.com>
References: <151627684798.24682.2979775081582774869.stgit@devbox>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <151627684798.24682.2979775081582774869.stgit@devbox>
User-Agent: Mutt/1.9.1 (2017-09-22)
X-getmail-retrieved-from-mailbox: INBOX
X-GMAIL-THRID: =?utf-8?q?1589931539308254743?=
X-GMAIL-MSGID: =?utf-8?q?1589935389093726734?=
X-Mailing-List: linux-kernel@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>

> Side effect: [1/3] will move __x86_indirect_thunk_* functions
> in kernel text area. Of course those functions were in the
> .text area, but placed in right after _etext. This just moves
> it right before the _etext.

I assume you tested that with page table isolation on?

The thunks need to be accessible from the trampoline.

-Andi