From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794246719; b=QYGAL8Pgfl9HNXkAFvF4jCxsCOXQKJuw1SClGQrtM7K1V5rqvKWg4O3deE9o831+9dPK 7W0rAUqRgBoXOOZAjCwjTtksPyGIFPy2JqSGJLQZl5XBnEIKXZu4Ip76fyZ4uaJwu70P+ A58bQu/yiOAtbxNypegW6VOmWPEFSEBcG0GaQ+komHFGf87AsB6PQp7WBAI4O6v4GNWuf MDZMs2qgiBzShOVGuxr5zHEZv7LQq2eWOW+RcYoi8O2HRNaD7ouAQi50aPKHTqvTKSb4x mRapJ0lImz9cxoEaCuivj5SkiDV1HFppLkD/0QwIkF7PHv7EMhvU2ZZM10zIfLpOwow== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794246719; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=i9Nv6xGB8Ae4NNlgpZyPMXjBlowBRSDkMgoiPDc8DSo=; b=k8Vo4ej4R/ZsFzQl2SnPEz4dOXAo3UXoXg1K8g1Co/co098JdtOcgS2lcMiCyBbJvgFh GI/aThaXgnhO0dKUJkYylUEKqwzZ/1zmhfVlUNKMDcKV7O+dVcN39ZOuJnSY7DtP4kH0O EYkhYaUZjHCESSrU6aBgo0Dtf1FLtYmB0aM3LGsB6MBmkpSW/I2jYVgm6MZ6b84Insgp+ 0VuYpX0ILyKmyhaHo61S6/irKIjAmiospA1BOWr4WwR6wLe2nF3dyHs2vFuOS9L+IAUEq BRP6AEBB4FmgNTQKSaUOGxn27/F+sBKM1G0R3NdB7RO5v+UQGrUsTqgJhzcRcXRnoTQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=ZYB6xKK7; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E745A606A33C; Mon, 9 Nov 2026 17:51:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=ZYB6xKK7 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0ECD01F008A5; Mon, 9 Nov 2026 17:51:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794246718; bh=i9Nv6xGB8Ae4NNlgpZyPMXjBlowBRSDkMgoiPDc8DSo=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=ZYB6xKK7ikHLcp12dpkvJj5Weru/Un6Bp2RAV9c3ZnLngBPdNf7jlFa/6pacFIadc d/pGjG87WyjjJobuh5kFUC1OQAoc9bRk4WC1pDEeCGQuKci+PF+Uw0eYMsHcnjtlLP s++NIZ8IZuJTW/rEM1mTa4fGTme1jNwWHMubKfSQJSK6DIM7cFtopEW3DmaocUcma+ CZXeDcWWnJz/AQVG1Gi3dP+iUzHahrZq6fKhJALiuBAIAGyYp7ziI2PuiuN8h+dcYJ nZjhtm8jNVudg+OXggV+9PHXgsxCrRE+ebIE0fV+E434lKUuqdYNDEcCFPIw0naYPj J7wdNcnd9Gi2g== Date: Mon, 9 Nov 2026 14:51:55 -0300 From: Arnaldo Carvalho de Melo To: Breno Leitao Cc: Kuniyuki Iwashima , Alan Maguire , Jiayuan Chen , netdev@vger.kernel.org, llvm@lists.linux.dev, ast@kernel.org, yonghong.song@linux.dev, bpf@vger.kernel.org, kuba@kernel.org, tj@kernel.org Subject: Re: [BUG] bpf: tcp: bpf_tcp_ops_set_rcvlowat() missing from BTF with clang KCSAN Message-ID: References: X-Mailing-List: netdev@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Mon, Nov 09, 2026 at 04:33:40AM -0800, Breno Leitao wrote: > On Fri, Nov 06, 2026 at 07:05:25PM +0000, Kuniyuki Iwashima wrote: > > On Fri, 06 Nov 2026 07:58:01 -0800, Breno Leitao wrote: > > > On Fri, Nov 06, 2026 at 09:16:24PM +0800, Jiayuan Chen wrote: > > > > Thanks for the report ! > > > > > > > > > > > > On 11/6/26 7:38 PM, Breno Leitao wrote: > > > > > My arm64 KCSAN builds of linux-next fail since next-20261015, because > > > > > bpf_tcp_ops_set_rcvlowat() is missing from the vmlinux BTF: > > > > > > > > > > WARN: resolve_btfids: no BTF func for kfunc bpf_tcp_ops_set_rcvlowat in bpf_tcp_ops_set_rcvlowat_kfunc_set > > > > > WARN: resolve_btfids: unresolved symbol bpf_tcp_ops_set_rcvlowat > > > > > Failed to generate BTF for vmlinux > > > > > Try to disable CONFIG_DEBUG_INFO_BTF > > > > > make[4]: *** [scripts/Makefile.vmlinux:72: vmlinux.unstripped] Error 1 > > > > Has pahole fixed this issue? > > > > > > I don't think so, see the line below: > > > > Could you try this ? > > Thanks, it fixes my build. I tested it on top of pahole master (9eb594d) > with next-20261105 and clang 22.1.3: > > - arm64 KCSAN, CONFIG_WERROR=y: vmlinux links again, > bpf_tcp_ops_set_rcvlowat() is back in BTF, __bpf_tcp_ops_init() > returns 0, and progs/tcp_autolowat.c from the selftests loads. > > - It also brings back scx_bpf_tid_to_task() that was work arounded by > tejun. > > Feel free to add my "Tested-by: Breno Leitao " tag. thanks, I'll check this later today, - Arnaldo