From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-198.mta1.migadu.com [95.215.58.198]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5BDD5239085 for ; Fri, 16 Oct 2026 05:49:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.198 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792129752; cv=none; b=O8hUlL7//KIzs05A8/FaGVnB1Q/YUUEtDKTUXktj0lUsmvNSrY6nnWtP7/qRLCdRcXYZThgCLWij+QjkcJ0kEmp3J/DdLOjgk0XdWtF/a0cQQE918+r7d9i4AAcOC8NBJw3dXcKMllJ5tWOh8UI1l8fKs+MnPBzpCGg3SbUsHeU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792129752; c=relaxed/simple; bh=n1U6JUPQS/QlQvnJNmSAj8kcYKjN2e1Oop2QgAyo+sM=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=eBPluE+GiD77h8zkijwEb80jatuBJQ9WUYNd8G/nEwUGb8PQwAlvWEismXzuOihWUlO+M9jUlihgD9DNNpQzemvFeD6zDeuBtWGcSLvYFGn9/5W+EWIguzhm4FD0ybjnteXtMQoBIxyMRGjf8Ks59t1X6H8axehXyvkWA6cxTXA= 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=X5WqFkRk; arc=none smtp.client-ip=95.215.58.198 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="X5WqFkRk" X-Envelope-To: bpf@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=n1U6JUPQS/QlQvnJNmSAj8kcYKjN2e1Oop2QgAyo+sM=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1792129747; v=1; x=1792734547; b=X5WqFkRk2kd2V24OVsVFlZuDinrzkfixOvgPcM1eeiNMUIy3/GAzlorrOT5EOXi8vNcBHJGy bqwo5I0duXuAeTBFXXzGFag6dNAib7tFMgbsWGeg/8DNLSX5cxzQrNmoh39b9rvjovXSUjRt+uc RAOTOL0gFudHUMbO5wNRH9MY= X-Envelope-To: bpf@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 7476dcd9d282368f; Fri, 16 Oct 2026 05:49:06 +0000 X-Mizu-Trace-ID: 7476dcd9d282368f X-Migadu-Flow: FLOW_OUT Message-ID: Date: Thu, 15 Oct 2026 22:49:01 -0700 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH bpf-next v1 5/8] bpftool: Emit __bpf_core_pso on verifier-rewritten context types To: Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , Eduard Zingerman , Kumar Kartikeya Dwivedi , Quentin Monnet Cc: bpf@vger.kernel.org, Alan Maguire , Cupertino Miranda , David Faust , Ian Rogers , "Jose E . Marchesi" , Vineet Gupta , Yonghong Song References: <20261016000012.2232059-1-ihor.solodrai@linux.dev> <20261016000012.2232059-6-ihor.solodrai@linux.dev> Content-Language: en-US From: Ihor Solodrai In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2026-10-15 6:27 p.m., Alexei Starovoitov wrote: > On Thu, Oct 15, 2026 at 05:00 PM Ihor Solodrai wrote: >> Clang 18 through 23 crash on __builtin_preserve_field_info over a PSO >> record, including bpf_core_field_*() and the CO-RE bitfield helpers. >> -D__bpf_core_pso= can disable PSO for affected programs. > > ouch. anyone working on fixing llvm ? I have a vibe coded fix, planned to review it and send a PR. > hopefully people don't do > bpf_core_field_exists(skb->tstamp_type) > when skb is __sk_buff. > > since nobody will know about -D__bpf_core_pso= workaround. When PSO lands, people might run into this as soon as they use new bpftool to generate vmlinux.h, and the failure is very loud. Since the bug is quite old, I am not sure it's feasible to fix it everywhere. Probably best we can do is advertise the workaround. > > Name is also not great. > "bpf_context" ? Yeah, the __bpf_core_ might not be the best name. I like btf_relocatable for PAI, should this be btf_unrelocatable?.. In any case this is bikeshedding, the macro is local to vmlinux.h, not a big deal.