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 2D0AC30DEB8; Thu, 11 Jun 2026 19:28:52 +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=1781206134; cv=none; b=Me/hP4DIAYQ77DDIb7DCf3KTPVP2OyF886GUWfS4e0L6nwwiHvkbfSGz7zI/hHAPAHzogoahJmfFXyf9oAaLyjUjEaPu8SVeZruBdTBcCxR5EQcthAPLMEJqPkkLryScHIw1xgI2c2hLJeQFolvtgXouzG+gcZdCk9d7dW1phh4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781206134; c=relaxed/simple; bh=p5QPawHMjTq8D3EPgkhTwPBzrNRu6zmFROilZF3lTHs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=c794DCcjQ7okZWYGhOuSS/2fF9TfiYQ7zOHiMX0BbwPCN6VvTc78FNri2G0TNLbNkZHNc7hnZN8aBeJoFQULPqlbI1I0ImMvB7l0wpU3+p9Y22cmR8nyNo5LK8wwujgADY16K+wQBy3NoQohfdT5zX1UgpKFmIPxjRNqJxBS+Gk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=pass smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=jOZvkt+0; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=pass 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="jOZvkt+0" 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=w0EWEUg0T2YXgOikKRNlNkeMOG3wiQMYZyZacU4kkh8=; b=jOZvkt+0AjfLO6hh+4KlqVZXse AEzINykqeIM66+ws4ZPJsz7cDE2ruJykb83jJlv950jQatWcgRj//maklA1NUOpUlbagoauwNp1D/ TyZJve0I4NSaN2S0fCbuWNEN08DumcPVkQQ+zoys1bU+tNZabeFSAknA3hVXrJ156yaKyoclj6haV GZfVIiZcpSD1NuWPBAfwOquzIj3oPiAKxl/n5sgblV2zyhPcMuBh4yAUctgE92T+ezhHgKmkdBDY8 oCmhcx31OFcsH8+Khmd/IY8MJSKuIa0+F+uMhLKYcVghw++GkXhZKYXHXQMJxcclV6cxSHnPUd9St 9h+4LQPA==; 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 4.99.2 #2 (Red Hat Linux)) id 1wXl55-00000005bMi-0TYi; Thu, 11 Jun 2026 19:28:47 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id EAD24300312; Thu, 11 Jun 2026 21:28:45 +0200 (CEST) Date: Thu, 11 Jun 2026 21:28:45 +0200 From: Peter Zijlstra To: Jens Remus Cc: Sami Tolvanen , Kees Cook , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Nathan Chancellor , Nick Desaulniers , Bill Wendling , Justin Stitt , linux-kernel@vger.kernel.org, llvm@lists.linux.dev, Heiko Carstens , Sashiko Subject: Re: [PATCH] x86/cfi: Use symmetric SYM_START and SYM_END in __CFI_TYPE() Message-ID: <20260611192845.GL187714@noisy.programming.kicks-ass.net> References: <20260611155716.830563-1-jremus@linux.ibm.com> Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260611155716.830563-1-jremus@linux.ibm.com> On Thu, Jun 11, 2026 at 05:57:15PM +0200, Jens Remus wrote: > Commit ccace936eec7 ("x86: Add types to indirectly called assembly > functions") introduced a x86-specific implementation of __CFI_TYPE() > using an asymmetric combination of SYM_START() and SYM_FUNC_END() to > add a symbol to the KCFI type identifier that precedes a function. > > This asymmetric combination is an issue if SYM_FUNC_END() ever gets > extended in a way that requires it to be used symmetrically with > SYM_FUNC_START*(). For instance to emit DWARF CFI directives that > denote the start/end of a function. [1] > > Use SYM_END() with SYM_T_FUNC instead. No functional change, as the > generic implementation of SYM_FUNC_END(name) expands into > SYM_END(name, SYM_T_FUNC). > > Reported-by: Sashiko > Closes: https://sashiko.dev/#/patchset/20260522110427.2816637-1-jremus@linux.ibm.com?part=3 [1] > Signed-off-by: Jens Remus Acked-by: Peter Zijlstra (Intel)