From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f179.google.com (mail-pl1-f179.google.com [209.85.214.179]) (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 2A2163859E9 for ; Mon, 24 Aug 2026 19:29:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.179 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787599798; cv=none; b=gDv0kDGKi8lRYXeceqRB8xrXTpHtuE/S1YdwUqs77Xcyk/qDHL0pX0KTAubqZDdCg9bDsr7VmG1FYswf4VR4gu+tJrolBPmaBdEhyccxBzMYbhcx+ab3fjfAjYJ0bmtyirYAsVh9XbHtfUh3wpJPStsDnHNlTX6jpyZnKUi3Sko= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787599798; c=relaxed/simple; bh=zifGuOdN5ZevE3gymhi79C8oJCbhUeEMc9C6UEgU2/s=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=OnBFkvTpZ6EJa8g+bd/IZu2dwBQjhmSJGHMyX0Yvwr8ftsHbtN4Zsm/mz8UM2Qw9U/RC6NSLQYB4UJ7321bf232gqUy70xXkAcoPA/7WkPWFYFg4ckmpgseN/c5SXbNgf1dUfsLSxJENpNRN9r33Vow8D6mwvqEpkFPV30qWAXc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=KNxIZAtH; arc=none smtp.client-ip=209.85.214.179 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="KNxIZAtH" Received: by mail-pl1-f179.google.com with SMTP id d9443c01a7336-2cacf197759so50678965ad.2 for ; Mon, 24 Aug 2026 12:29:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1787599796; x=1788204596; darn=vger.kernel.org; h=mime-version:user-agent:content-transfer-encoding:content-type :references:in-reply-to:date:cc:to:from:subject:message-id:from:to :cc:subject:date:message-id:reply-to:content-type; bh=zifGuOdN5ZevE3gymhi79C8oJCbhUeEMc9C6UEgU2/s=; b=KNxIZAtHJ4rFirPA9Z9LWyDI+shZ6ivUTx9G4QsktAq1iLTqU8n41yCGquNhdFj9Cz 3g5iRNRyg/dsHhxwslK+5fhsI0/0MWSFdFaRDdSlGxwY3Ra8eG97R6SfXQlLhU+5025v huc64uscYXIAvNMD97vdcdljnrM50MtuQI6/Nx5AfB+rQhbKj2+rZOGGdMGY+Layd2pV OLCAPRmpWgpyYuwxnRr980dcCbyBdd17yoYZlqCs1yEdxxepUSpSA8PsKGn0JgqFGqyT KlehUL9H6BcG9RaV5GyMtHtF9MF7WHb/1weWpp1nb+iemPWLM3xV05eKjqEpezXfnMgG 6tug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1787599796; x=1788204596; h=mime-version:user-agent:content-transfer-encoding:content-type :references:in-reply-to:date:cc:to:from:subject:message-id:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=zifGuOdN5ZevE3gymhi79C8oJCbhUeEMc9C6UEgU2/s=; b=WqQ7VrQoNwDNp0jfSVeD14YGpjTFMFuiFjcAP0PGkv/AiGS8VEhTuw14rQz5aREWYN Ri1t5/k2JVMB5O3YS2R3XNYo/Qenajxy4cwQqA69favINmTtsiQX+OOt3IayoyOKytdv QSqukiJVL0KEzASamGJeYSchcnOE3LX4AFpDZDVuk1gMvZKHMup7Xc6ZPsAzQCkUtMn+ EGs26Ha4LoZVvReNFKFMljk0xQYx1karu/pXxKh8bPMQcZd654rkuVwprpZPJ5QfsuUU INTiD8iE7Eq2kLE7OjYj6ykkuJaWMtUrd1gco5p0smpYrMaK0exL6sYP7rGMtezGxPDE ChOw== X-Forwarded-Encrypted: i=1; AHgh+RokdRfK5dqa0cyUxZLa/Y6xFJtJy4hwO8Txko7PXYM8lJyKelKKPn5U1h/JusS1aBzwGXg=@vger.kernel.org X-Gm-Message-State: AFuF++lN78t9TLuO0wDvUUoVvq0IVjLNMKNze5S00fDf9Pyn54nqXKte AzimAVLB6dzcL4f0mVFeRTe8ufHdwMTx5vdZT0OtUCktNa6Bzhiw5DGV X-Gm-Gg: AR+sD10gim2I6rATj6sPiwxbKPVt90mLNZPREgNyOP2bv26XRwVXIEHChWd3t6GZQKY eZipvyq1PjMKHxxr4hO4UWvKu8ey4e+4htSq93BIGyv45RNvi7zqa+U9qJa8qajPK3MbxZIwOft BboWW1+o3MlJKZdXVSNXFfbrHpQgJTTJKaPZq/Mcuy2smus1ZrlXpmoH5i9xiRFlYWeBl41EpHx ezBFTTutlrYqb+N8FTKiq69hMzJJgimOC8AreZSIuYVCkcPXIlG814fPQ4HYXixJwpW7NvPa++R 9WSn17fmv5oIfkIuGAhDfr2jHsEZRHHk8nmuz6vN21JfVwZQixzktIWHaTH6KRAAn8knq3RrTmk Zmyl64ZgXgLbz2ryF0iNWIHBOvuEi4mXo8RBoTqVCGOhqcossgsy0kKWLxyV7vA42nVVFz1R//e DKYkrshK0tB8U2ZtbrEgUv/9xfYT7excHvF05j50vrT1+WNbZLPypolCNN39JpOyogpnPvbNilB 1uGRBCTVVlyY/t0KkvE+W+gP2zXrFVm+4pvlnah0OBbWA== X-Received: by 2002:a17:902:d54a:b0:2d0:cc92:f7ae with SMTP id d9443c01a7336-2d6dcadc96emr31713895ad.3.1787599796444; Mon, 24 Aug 2026 12:29:56 -0700 (PDT) Received: from ?IPv6:2a03:83e0:115c:1:21a6:ad3f:64a7:7661? ([2620:10d:c090:500::5:ef40]) by smtp.gmail.com with ESMTPSA id 5a478bee46e88-327f9209f51sm47284796eec.22.2026.08.24.12.29.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 24 Aug 2026 12:29:56 -0700 (PDT) Message-ID: <46c1cd1bc396ffce77024b1bb7e2bb8c81c20905.camel@gmail.com> Subject: Re: [PATCH bpf-next 1/2] bpf: Record each half of a paired return value in verifier diagnostics From: Eduard Zingerman To: Yonghong Song , bpf@vger.kernel.org Cc: Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , kernel-team@fb.com Date: Mon, 24 Aug 2026 12:29:54 -0700 In-Reply-To: <20260824144943.991316-1-yonghong.song@linux.dev> References: <20260824144943.991316-1-yonghong.song@linux.dev> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.60.2 (3.60.2-1.fc44) Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Mon, 2026-08-24 at 07:49 -0700, Yonghong Song wrote: > A subprogram returning more than 8 bytes comes back in the R0:R2 register > pair, and prepare_func_exit() copies both registers into the caller. The > diagnostic modification scope around that copy names only R0, so the writ= e > into R2 is never recorded. >=20 > Fix it by opening a diagnostic modification scope for each return registe= r. > This way, both return registers are recorded. >=20 > Fixes: 0630ad00d96d ("bpf: Add verifier support for 16-byte returns in R0= : R2") > Signed-off-by: Yonghong Song > --- Acked-by: Eduard Zingerman ...