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 2383919F12A; Wed, 3 Sep 2025 23:09:45 +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=1756940986; cv=none; b=Jx4kDDdeM2UB322iST8ZX7QTcxYp9etpuYiJY7oPC3QIheQP6ols7f/9dcF25IgL84EUyp6fo69pwFwwmK01OVK16pJpb/LNlFtt//o7fFdVI5wxfdIjOxp3sN3+z5oprGmln6stQA9ZVdw44QVhwJ33o1Ouj+y2Eg6ERzt4VNI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756940986; c=relaxed/simple; bh=MnK5x+u2vsPXChCOwxVvcYRQZplc/jyPK8RAoWfnHi0=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=hZBsWUl1qaf4hYqFpUgimDbYU8b2SQBRJc4ViYHJPJbGGRpeWa7XXqIWrU9ddzXGtjsEIs7VETL5s+2f0BAO/FLg2ZHGfL9I0oXPrIxht73PR7MT31A6gnbudFI5BIVeqX3UYkdyvlxTl/yBJ05M6y++3S3CG9meGHKMku3cqKk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tITAqU+S; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="tITAqU+S" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5FF9AC4CEE7; Wed, 3 Sep 2025 23:09:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1756940985; bh=MnK5x+u2vsPXChCOwxVvcYRQZplc/jyPK8RAoWfnHi0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=tITAqU+S6D1DX72m9n4YtUvDUDRaHlrMFN9k3XZPR3JQ1lSOv2ql64hxXM4K6uLDz 9XDBZ6Ao4LNpfimuotUaBNu1Jqv2T+qj+vdVyc664H+3kkv+Fy8o1LaBDsR54JJeW5 WfAPlkgJCx27MRzTdEyULR9cRkrTvaNIuXIecWNlToiHlsucIJN8kldnitvUKR2BvG goD33eW5RHWckONI0vcagIYYZTdijmiLAkA9OY3LKpwNVdWKIJbpggGmiwygereOxo 4Aow0nehnDx9kDq4+nmd1A5GNa9ZEjalGkrQ701zC0jNytrSkQJa+R9Xp8fMCoN53G rFsb9ib80i01w== Date: Wed, 3 Sep 2025 16:09:44 -0700 From: Jakub Kicinski To: Florian Westphal Cc: netdev@vger.kernel.org, Paolo Abeni , "David S. Miller" , Eric Dumazet , netfilter-devel@vger.kernel.org, pablo@netfilter.org Subject: Re: [PATCH net 1/2] selftests: netfilter: fix udpclash tool hang Message-ID: <20250903160944.27826c84@kernel.org> In-Reply-To: References: <20250902185855.25919-1-fw@strlen.de> <20250902185855.25919-2-fw@strlen.de> <20250903151554.5c72661e@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Thu, 4 Sep 2025 00:52:20 +0200 Florian Westphal wrote: > Jakub Kicinski wrote: > > On Tue, 2 Sep 2025 20:58:54 +0200 Florian Westphal wrote: =20 > > > Yi Chen reports that 'udpclash' loops forever depending on compiler > > > (and optimization level used); while (x =3D=3D 1) gets optimized into > > > for (;;). Switch to stdatomic to prevent this. =20 > >=20 > > gcc version 15.1.1 (F42) w/ whatever flags kselftests use appear to be > > unaware of this macro: > >=20 > > udpclash.c:33:26: error: implicit declaration of function =E2=80=98ATOM= IC_VAR_INIT=E2=80=99; did you mean =E2=80=98ATOMIC_FLAG_INIT=E2=80=99? [-Wi= mplicit-function-declaration] > > 33 | static atomic_int wait =3D ATOMIC_VAR_INIT(1); > > | ^~~~~~~~~~~~~~~ > > | ATOMIC_FLAG_INIT > > udpclash.c:33:26: error: initializer element is not constant > > Could you perhaps use volatile instead? =20 >=20 > That works too. I'll send a new PR tomorrow, its late here. =F0=9F=91=8D=EF=B8=8F FWIW I'll be sending the PR tomorrow so plenty time..