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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31DDCC678D5 for ; Tue, 7 Mar 2023 17:27:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229907AbjCGR1G (ORCPT ); Tue, 7 Mar 2023 12:27:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51232 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231562AbjCGR0i (ORCPT ); Tue, 7 Mar 2023 12:26:38 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 037971555A for ; Tue, 7 Mar 2023 09:21:36 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 93AC8614D0 for ; Tue, 7 Mar 2023 17:21:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8A179C433EF; Tue, 7 Mar 2023 17:21:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678209695; bh=5KY4ObnIs4ioAsY4kJN5gQ/ImV2ynce+cM+CruzdSSw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=v3oamINsk+UsHxeda1QZdLqnvFuS2zsq55LJ5aeEdmSst4PYrt+Q/s1UUo93Q1CLq 4uPYYhxORYxmU9SoY1n+GubloWIXCyzJb2zG4DxhB0dbNTb2/GqTGPm+fQCZ5EOZay 1sTY2XKC3UjIiZMK92FmaqeYRfeBk2YXFYsBf8PA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Arnd Bergmann , Johannes Berg , Sasha Levin Subject: [PATCH 6.2 0302/1001] wifi: mac80211: avoid u32_encode_bits() warning Date: Tue, 7 Mar 2023 17:51:14 +0100 Message-Id: <20230307170034.683100954@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230307170022.094103862@linuxfoundation.org> References: <20230307170022.094103862@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Arnd Bergmann [ Upstream commit 1d8d4af4347420d657be448f8be4c39c558f3b5d ] gcc-9 triggers a false-postive warning in ieee80211_mlo_multicast_tx() for u32_encode_bits(ffs(links) - 1, ...), since ffs() can return zero on an empty bitmask, and the negative argument to u32_encode_bits() is then out of range: In file included from include/linux/ieee80211.h:21, from include/net/cfg80211.h:23, from net/mac80211/tx.c:23: In function 'u32_encode_bits', inlined from 'ieee80211_mlo_multicast_tx' at net/mac80211/tx.c:4437:17, inlined from 'ieee80211_subif_start_xmit' at net/mac80211/tx.c:4485:3: include/linux/bitfield.h:177:3: error: call to '__field_overflow' declared with attribute error: value doesn't fit into mask 177 | __field_overflow(); \ | ^~~~~~~~~~~~~~~~~~ include/linux/bitfield.h:197:2: note: in expansion of macro '____MAKE_OP' 197 | ____MAKE_OP(u##size,u##size,,) | ^~~~~~~~~~~ include/linux/bitfield.h:200:1: note: in expansion of macro '__MAKE_OP' 200 | __MAKE_OP(32) | ^~~~~~~~~ Newer compiler versions do not cause problems with the zero argument because they do not consider this a __builtin_constant_p(). It's also harmless since the hweight16() check already guarantees that this cannot be 0. Replace the ffs() with an equivalent find_first_bit() check that matches the later for_each_set_bit() style and avoids the warning. Fixes: 963d0e8d08d9 ("wifi: mac80211: optionally implement MLO multicast TX") Signed-off-by: Arnd Bergmann Link: https://lore.kernel.org/r/20230214132025.1532147-1-arnd@kernel.org Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin --- net/mac80211/tx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index defe97a31724d..118648af979c7 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -4434,7 +4434,7 @@ static void ieee80211_mlo_multicast_tx(struct net_device *dev, u32 ctrl_flags = IEEE80211_TX_CTRL_MCAST_MLO_FIRST_TX; if (hweight16(links) == 1) { - ctrl_flags |= u32_encode_bits(ffs(links) - 1, + ctrl_flags |= u32_encode_bits(find_first_bit(&links, 16) - 1, IEEE80211_TX_CTRL_MLO_LINK); __ieee80211_subif_start_xmit(skb, sdata->dev, 0, ctrl_flags, -- 2.39.2