From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E4DF7C2BA19 for ; Sat, 4 Apr 2020 05:14:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BB5D2206D4 for ; Sat, 4 Apr 2020 05:14:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Gkz39G++" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726077AbgDDFOk (ORCPT ); Sat, 4 Apr 2020 01:14:40 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:51563 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725957AbgDDFOk (ORCPT ); Sat, 4 Apr 2020 01:14:40 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1585977278; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=ZpFf/EoCFh5H+QhRcDIRFMLkLiYNbq7Buj4lk/PV9+E=; b=Gkz39G++aYlnMkwUgw1TjGcNADhbWXvaH3nYNBLmmCHtbj8LoS0cHfD2+CG1Z7RKE+SIk6 wHeg4Hz1R6JC84u1++NS6dO44BZ6ZO5jK1RngfFl7FKmCgy1o9/Ek7uAPHAUMt+Jy4rf6f guHlY/h1+Z3fa/76SI+mvaTlxfrKl2g= Received: from mail-qv1-f70.google.com (mail-qv1-f70.google.com [209.85.219.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-276-0xgC6SnvMRSLsmNc8VYbNg-1; Sat, 04 Apr 2020 01:14:36 -0400 X-MC-Unique: 0xgC6SnvMRSLsmNc8VYbNg-1 Received: by mail-qv1-f70.google.com with SMTP id h12so7735518qvx.10 for ; Fri, 03 Apr 2020 22:14:36 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=ZpFf/EoCFh5H+QhRcDIRFMLkLiYNbq7Buj4lk/PV9+E=; b=p/IVH847ACs3AoDvLjiPvlnIRvQJTo+Zs8gYN1l38B9VdXXZgBR/fCxvwH/CReLWFj /WrPOuyWHwXt5St7wJ41yJR0JGWdf43qN9QllbhB19fuCFR47yPRxiwFjT4IFrJ69sY0 CXcXxbtYfmSy/XAmftGfj2bAKuX3bRtnBxAv4ypswjNEsJvpLjF30o7br0uAJ1NgsKvZ oCDfFjzzathafP/KT0A8bNrcVc9PS65wmRE3lRSLKtFcfc+Qu+KdLKdOI1loIX4WSzOh RUelAEHvMai+gkP8avcb5OGViPqkHVvNuCoOUA1o9zzp8nfIxFiDJJQGVHMy1d8hK+t3 LlKg== X-Gm-Message-State: AGi0PuYIOCAM89kghkHh3T/RdxMlOgOf5XIe4Ty72CEqZ7dl+MhIUXDZ lZ9bdEho30zkqvDrnDvCQ4MeGeSuVK2d9e3PErdPltNoF9T1cWR33lkvsXvprxyCnc6zVpF2kMG qIc6S/V/ZNV8d8Z6gE9OBKaIh X-Received: by 2002:a37:bc81:: with SMTP id m123mr12055897qkf.319.1585977276502; Fri, 03 Apr 2020 22:14:36 -0700 (PDT) X-Google-Smtp-Source: APiQypKViJKhK46Bek5h3iQkjtptKzLOTEk2G1SgElgDH20cPIvTEPA2VrkO8I0zh/Xbyt+SD5/dCQ== X-Received: by 2002:a37:bc81:: with SMTP id m123mr12055873qkf.319.1585977275982; Fri, 03 Apr 2020 22:14:35 -0700 (PDT) Received: from dev.jcline.org.com ([136.56.87.133]) by smtp.gmail.com with ESMTPSA id t23sm8844247qtj.63.2020.04.03.22.14.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 03 Apr 2020 22:14:35 -0700 (PDT) From: Jeremy Cline To: Alexei Starovoitov , Daniel Borkmann Cc: Martin KaFai Lau , Song Liu , Yonghong Song , Andrii Nakryiko , John Fastabend , KP Singh , "David S . Miller" , Jakub Kicinski , Jesper Dangaard Brouer , netdev@vger.kernel.org, bpf@vger.kernel.org, linux-kernel@vger.kernel.org, Jeremy Cline Subject: [PATCH] libbpf: Initialize *nl_pid so gcc 10 is happy Date: Sat, 4 Apr 2020 01:14:30 -0400 Message-Id: <20200404051430.698058-1-jcline@redhat.com> X-Mailer: git-send-email 2.26.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Builds of Fedora's kernel-tools package started to fail with "may be used uninitialized" warnings for nl_pid in bpf_set_link_xdp_fd() and bpf_get_link_xdp_info() on the s390 architecture. Although libbpf_netlink_open() always returns a negative number when it does not set *nl_pid, the compiler does not determine this and thus believes the variable might be used uninitialized. Assuage gcc's fears by explicitly initializing nl_pid. Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1807781 Signed-off-by: Jeremy Cline --- tools/lib/bpf/netlink.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/lib/bpf/netlink.c b/tools/lib/bpf/netlink.c index 18b5319025e19..9a14694176de0 100644 --- a/tools/lib/bpf/netlink.c +++ b/tools/lib/bpf/netlink.c @@ -142,7 +142,7 @@ static int __bpf_set_link_xdp_fd_replace(int ifindex, int fd, int old_fd, struct ifinfomsg ifinfo; char attrbuf[64]; } req; - __u32 nl_pid; + __u32 nl_pid = 0; sock = libbpf_netlink_open(&nl_pid); if (sock < 0) @@ -288,7 +288,7 @@ int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info, { struct xdp_id_md xdp_id = {}; int sock, ret; - __u32 nl_pid; + __u32 nl_pid = 0; __u32 mask; if (flags & ~XDP_FLAGS_MASK || !info_size) -- 2.26.0