From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 D1B191A76D4; Tue, 30 Jul 2024 17:16:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722359765; cv=none; b=GDzQ7md0JK5CRzqoYCCxZaG9XZn/ZknrQT81K8iCK/3Rc9teaUuLgV42k72Mmc5QzVlpBwUFauZ3D0KWck60Jery60G12/d3dxbdpAnZxljvWAcWqBfrZn0nnJrAOE7hz6DUDlnpZNK/V3TCrDCo2MDoiiLBgZvCObwO19FWSO4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722359765; c=relaxed/simple; bh=HhWgQsg9uJpQsfycDU18WGuGyBUl5nO34UU/NaQd9L0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DXjJpvds7slr8IHOuw72lj99Ao0MwCR0Qv/peg9KnCdcKRJHUb34CglBLZvYdXkZBAEvmXzPpyfTzK6bZNd59Fr23YKX0v4hX62oOslou/buy/IB+mzdR0ubobI5HvBxGX30Wn4eQcoXSvzSlwfkbDYcCaQ0bMQk+7PfUkiPLMc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=TAzvl5EW; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="TAzvl5EW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 51620C32782; Tue, 30 Jul 2024 17:16:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1722359765; bh=HhWgQsg9uJpQsfycDU18WGuGyBUl5nO34UU/NaQd9L0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TAzvl5EWvtAiERuhLmNkHnUtPOpp6yuDgAMm7At48T8H2duptvAuUAvaU5XdtZedT dqnDi+kqrmuHnoWLktqwRkEH/6z/IzMJm71/d0tkQAYRX5PEY2wDPFU/dkXJdSJ9MO u/rjEo6uq74EMVPdpe1qilCo25rGlNvsk0ghw98U= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Hou Tao , Daniel Borkmann , Yonghong Song , Krister Johansen , Jiri Olsa , Sasha Levin Subject: [PATCH 6.6 533/568] bpf, events: Use prog to emit ksymbol event for main program Date: Tue, 30 Jul 2024 17:50:40 +0200 Message-ID: <20240730151700.988381052@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240730151639.792277039@linuxfoundation.org> References: <20240730151639.792277039@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hou Tao [ Upstream commit 0be9ae5486cd9e767138c13638820d240713f5f1 ] Since commit 0108a4e9f358 ("bpf: ensure main program has an extable"), prog->aux->func[0]->kallsyms is left as uninitialized. For BPF programs with subprogs, the symbol for the main program is missing just as shown in the output of perf script below: ffffffff81284b69 qp_trie_lookup_elem+0xb9 ([kernel.kallsyms]) ffffffffc0011125 bpf_prog_a4a0eb0651e6af8b_lookup_qp_trie+0x5d (bpf...) ffffffff8127bc2b bpf_for_each_array_elem+0x7b ([kernel.kallsyms]) ffffffffc00110a1 +0x25 () ffffffff8121a89a trace_call_bpf+0xca ([kernel.kallsyms]) Fix it by always using prog instead prog->aux->func[0] to emit ksymbol event for the main program. After the fix, the output of perf script will be correct: ffffffff81284b96 qp_trie_lookup_elem+0xe6 ([kernel.kallsyms]) ffffffffc001382d bpf_prog_a4a0eb0651e6af8b_lookup_qp_trie+0x5d (bpf...) ffffffff8127bc2b bpf_for_each_array_elem+0x7b ([kernel.kallsyms]) ffffffffc0013779 bpf_prog_245c55ab25cfcf40_qp_trie_lookup+0x25 (bpf...) ffffffff8121a89a trace_call_bpf+0xca ([kernel.kallsyms]) Fixes: 0108a4e9f358 ("bpf: ensure main program has an extable") Signed-off-by: Hou Tao Signed-off-by: Daniel Borkmann Tested-by: Yonghong Song Reviewed-by: Krister Johansen Reviewed-by: Jiri Olsa Link: https://lore.kernel.org/bpf/20240714065533.1112616-1-houtao@huaweicloud.com Signed-off-by: Sasha Levin --- kernel/events/core.c | 28 +++++++++++++--------------- 1 file changed, 13 insertions(+), 15 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 32723d53b970b..1b728f3f4b539 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -9273,21 +9273,19 @@ static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; int i; - if (prog->aux->func_cnt == 0) { - perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, - (u64)(unsigned long)prog->bpf_func, - prog->jited_len, unregister, - prog->aux->ksym.name); - } else { - for (i = 0; i < prog->aux->func_cnt; i++) { - struct bpf_prog *subprog = prog->aux->func[i]; - - perf_event_ksymbol( - PERF_RECORD_KSYMBOL_TYPE_BPF, - (u64)(unsigned long)subprog->bpf_func, - subprog->jited_len, unregister, - subprog->aux->ksym.name); - } + perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, + (u64)(unsigned long)prog->bpf_func, + prog->jited_len, unregister, + prog->aux->ksym.name); + + for (i = 1; i < prog->aux->func_cnt; i++) { + struct bpf_prog *subprog = prog->aux->func[i]; + + perf_event_ksymbol( + PERF_RECORD_KSYMBOL_TYPE_BPF, + (u64)(unsigned long)subprog->bpf_func, + subprog->jited_len, unregister, + subprog->aux->ksym.name); } } -- 2.43.0