From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BDF00C433EF for ; Fri, 25 Feb 2022 19:53:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235515AbiBYTyN (ORCPT ); Fri, 25 Feb 2022 14:54:13 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235195AbiBYTyL (ORCPT ); Fri, 25 Feb 2022 14:54:11 -0500 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A31F8D0079 for ; Fri, 25 Feb 2022 11:53:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=HZTrg86cU89/EReneceXoP7zTLrnbBBH3OgsInB7sow=; b=QYAirtx2iGAq8YTBKxlVCjXzGD 0+bdQGA1KQouYWwaCd/G9OnDSgkCQNi/L6z2a4iapL7BFgJxDFpd1B0SjZhZJpu3CezbcIToAPm0k rdCodNYhIrDJGEF8+tyZl6JVS3twP5o2WBcxvGBl8Tbfys08D6o1eQh9zq1zCw0sq2TSzbJZuoVr3 gpGjOfG2oBDxhYjoPgPf41w6WXTrQuNzLYg7cKCc4bp8MeTcpK5vN9iB1cKsDBcHpDsLl2921L+3L PNUIzovUbaInV3EAuA9mF91Jo1TU8fRGPfocEx6txK1XyiUajyYA+Hz+sz5sU5htTKtcFuaqYmDA9 D+QqetFA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=worktop.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nNgeH-00D2NY-MS; Fri, 25 Feb 2022 19:53:06 +0000 Received: by worktop.programming.kicks-ass.net (Postfix, from userid 1000) id E365C986AEC; Fri, 25 Feb 2022 20:53:03 +0100 (CET) Date: Fri, 25 Feb 2022 20:53:03 +0100 From: Peter Zijlstra To: Steven Rostedt Cc: Josh Poimboeuf , x86@kernel.org, joao@overdrivepizza.com, hjl.tools@gmail.com, andrew.cooper3@citrix.com, linux-kernel@vger.kernel.org, ndesaulniers@google.com, keescook@chromium.org, samitolvanen@google.com, mark.rutland@arm.com, alyssa.milburn@intel.com, mbenes@suse.cz, mhiramat@kernel.org, alexei.starovoitov@gmail.com Subject: Re: [PATCH v2 00/39] x86: Kernel IBT Message-ID: <20220225195303.GA11184@worktop.programming.kicks-ass.net> References: <20220224145138.952963315@infradead.org> <20220224202602.3gvz5tnxvwb4maod@treble> <20220225172644.76fyxjximjrcdbzt@treble> <20220225123238.5ceeaae1@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220225123238.5ceeaae1@gandalf.local.home> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 25, 2022 at 12:32:38PM -0500, Steven Rostedt wrote: > On Fri, 25 Feb 2022 09:26:44 -0800 > Josh Poimboeuf wrote: > > > > Damn, I just realized this makes KERNEL_IBT hard depend on KALLSYMS :-( > > > > Why should the jump label patching code even care whether there's an > > ENDBR at the jump target? It should never jump to the beginning of a > > function anyway, right? And objtool presumably doesn't patch out ENDBRs > > in the middle of a function. > > Perhaps Peter confused jump labels with static calls? The code is shared between the two.