From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-186.mta1.migadu.com (out-186.mta1.migadu.com [95.215.58.186]) (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 631211CAA7D for ; Wed, 1 Jul 2026 06:22:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.186 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782886938; cv=none; b=lZT3//6X3KbFQtgi4UoyY4Nl1l+sUl3btouiioogRGXRaMIh5pfQ26+7mz5EEVYILCRXA3BWV3rYndzUmRRkH4VUEWx7DhmiW88VCW4q22ys5ol7C7jOVmEEwJmVBB/XIA0Y1SsskBqzsxKi8xj8eE+dV+TjXO/jxVrTs4DKISE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782886938; c=relaxed/simple; bh=vDGAhh3K7WmphlzICZtxnZYyBZQK+/l7wgZ+PvyZHyE=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=BFH1T0Aen52E3y1CZthzhmub89FaQa7WKAvhBTyo5zagys8mvCR4D0scmdD/4Yysq6PDUQiJdwQ+uaBxDbMhesrnTrlp1BNa5O+/DmIYdts6p8azMz3EvsKlHggoUCKg79qHTpWcjJ1IRgSEFedMc+xrmKonWUBYEqlCATTa7h4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=ny25sP3K; arc=none smtp.client-ip=95.215.58.186 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="ny25sP3K" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1782886935; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=e0T3+Xzz4JF6iqR2a0ZXe4TdO1iGWVdDl3TlKLhVxfA=; b=ny25sP3Kf5KHYcWTmYTSFokPp9lQ2ZQnEQxM9S+5A04IK+qmWeHROVHLlQUbvZcOFzCk6A wSv7p0xrg6qHWPDNd2v+88o0mavf6UCHFcJFOOiVGMFIxGmzkPGk4RfoYU/l11FoOCUjx0 wlujGGNK0LeDF4gjLM4s5YEHk3LOyS4= Date: Wed, 1 Jul 2026 14:21:59 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [RFC PATCH bpf 1/6] bpf: Disallow interpreter fallback for user BPF_ADDR_SPACE_CAST insn Content-Language: en-US To: Tiezhu Yang , KaFai Wan , bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Eduard Zingerman , Kumar Kartikeya Dwivedi , Martin KaFai Lau , Song Liu , Yonghong Song , Jiri Olsa , Emil Tsalapatis , Andrew Morton , Shuah Khan , Puranjay Mohan , Anton Protopopov , linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org References: <20260626154330.33619-1-leon.hwang@linux.dev> <20260626154330.33619-2-leon.hwang@linux.dev> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Leon Hwang In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 1/7/26 09:26, Tiezhu Yang wrote: [...] > > Hi all, > > Alexei said in another thread like this: > > ``` >> [3] https://lore.kernel.org/bpf/20260615025316.24429-1- > yangtiezhu@loongson.cn/ > > I don't think we need such fallback in patch [3]. > ``` > https://lore.kernel.org/bpf/DJMRIZ5PDWP4.12OOZ8H881H6O@gmail.com/ > > Should I just drop my previous patch? To be honest, I'm not sure how to > solve the issue mentioned in it. Is that a real problem, and does it > need to be fixed? What is the next step? > It is a real issue. Instead of fixing up helper calls, it seems better to prevent interpreter fallback if the prog has any JIT-inlineable helper call. Thanks, Leon