From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EEE7C23370F; Mon, 24 Feb 2025 12:35:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740400542; cv=none; b=gTkeNogojv0Qqpm2pKkfV6s2CSwIK1vUAqblLEKJrC9O+U0LNFgBCzaIzgK6Lz9gih1lYjNW3bRqspnKhrhEhxhvif52+0lHzICkHLejA9a5svxh3G/JstY0jwG229I76atoY8VHeJXvq+1RT743vv5tC5Y7YFfyr6U0O3iMTiw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740400542; c=relaxed/simple; bh=s/KOZT8FuLlCPeUB5JVASVwIWTkII3PCu9vNrjIh9SI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=YpIrCi2quXmoyl7Vua4Ndn5PkzLEsqxiceBeg54qn3AGprD9AxV398Gpne/F2RdIsxMhCgxk/u9D1W0lb3xCXXtSeK6v6Ig4FPPrY6F7HN9pd8qrmB7KDC03OjC/G1R4gIhXQewNzsuSNqtlWu9V00sE1hattEHGmQgGwHnNN7k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=CiPkSzWk; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="CiPkSzWk" 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=KjNIYWV63wd2ETJVPJjYoHVaRj09KcDEXGN6j/BKYZs=; b=CiPkSzWklbhO7mPKl1Jriapzi/ h9ZxgOOaJCqDCX7rY6o0B7nUEflSjApS0qhasUcWF4BOkhJEwhaYfuv99XToeUmJQw2+kR6W5WrhW OwHnhVNyz53GmSNgcjiXOMIlxaXMZ0jwdb4zAwnzMZ4zeug+JEniisIxMNgEmiqKuCkxUOCf72gjQ oTHbKpc43qi+xEsISsUdjmrcR0JdWeEOh3E9X9GVJYKXcwRew5f16ANwoYvi3KnMMjz5NxnyR5eZs Kaqfcp2voEqtm9ZcyMIA26TvS5hyeuZL36CiNSnC/JxZQm22QlYAxSDZQwcmduj7p2AXViJBxosAl /Ur+1niw==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98 #2 (Red Hat Linux)) id 1tmXgO-00000003Bsx-0elI; Mon, 24 Feb 2025 12:35:36 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id B45A4300164; Mon, 24 Feb 2025 13:35:34 +0100 (CET) Date: Mon, 24 Feb 2025 13:35:34 +0100 From: Peter Zijlstra To: Sathvika Vasireddy Cc: Josh Poimboeuf , christophe.leroy@csgroup.eu, npiggin@gmail.com, maddy@linux.ibm.com, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, llvm@lists.linux.dev Subject: Re: [RFC PATCH] objtool: Skip unannotated intra-function call warning for bl+mflr pattern Message-ID: <20250224123534.GB17456@noisy.programming.kicks-ass.net> References: <20250219162014.10334-1-sv@linux.ibm.com> <20250220195940.ely2l2fpsozd2tuv@jpoimboe> <4bea75bc-d3f6-4972-b644-f9b5a4e8bb77@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4bea75bc-d3f6-4972-b644-f9b5a4e8bb77@linux.ibm.com> On Fri, Feb 21, 2025 at 02:20:41PM +0530, Sathvika Vasireddy wrote: > Also, just out of curiosity, how does x86 do it? Does it not use a branch to > next instruction approach? x86_64 can use LEA like: #define _THIS_IP_ ({ unsigned long __here; asm ("lea 0(%%rip), %0" : "=r" (__here)); __here; }) 32bit needs to call a function, read the stack value and return.