From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-98.freemail.mail.aliyun.com (out30-98.freemail.mail.aliyun.com [115.124.30.98]) (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 988BB4C74; Mon, 13 May 2024 15:06:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.98 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715612814; cv=none; b=C1/CT1NSJKoEzoWpxQPbT2bQJRQ11wTwwoKBw1adBdm/BW1VxSM4sBUCtxjFNQXCU7tdzKv89Tp3x8tVuuMLfF+OkWIAjGyRag/hhKFgVxHevicVMCnSNJee+WqRQs5i/6AgfrbdARrJe4DXfIit/Ywy/1UB3VnQ/XT8Ao6/I5A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715612814; c=relaxed/simple; bh=y609Cc4cYkc6pEsR0kIAiOhx1xZxh+tw/aoYwkH85eA=; h=Message-ID:Subject:Date:From:To:Cc:References:In-Reply-To; b=TBmkZoOwUokLn2YSkQ+PKijPcNraWvECi/IjFZbjyXoU+4nygj+nwTgmgtBzEGMXENMGwNpBWt5Ths58iax2ca6m5YfzXec5LcakVXMiaVFiww/rnt9a1TahW0e+c3ftgfI5F+NKfz4xroFfmmyPq8HAW8BO28asSTeQ7OdZ82I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=ygnxlBGL; arc=none smtp.client-ip=115.124.30.98 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="ygnxlBGL" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1715612806; h=Message-ID:Subject:Date:From:To; bh=7MLM12E9blsRkdX77DqwhU+UpqcO9mhaNTsXw3y52Tg=; b=ygnxlBGLKmyp8lSYi8NVkk1vufURUaezThVgzi4y6boS8HScpKqgZN0CYgMjk3Qrv4JN2TG0KfqEzFVRSzWf07qYrV2ER77XPLMyoG1G6iOou2we3xlFepCw1g6V/K/9LfG8YuueBJqdXlVge1jZLN3huv2ASwk2D6ftwoyA/1Q= X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R381e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033022160150;MF=hengqi@linux.alibaba.com;NM=1;PH=DS;RN=27;SR=0;TI=SMTPD_---0W6SIWe7_1715612804; Received: from localhost(mailfrom:hengqi@linux.alibaba.com fp:SMTPD_---0W6SIWe7_1715612804) by smtp.aliyun-inc.com; Mon, 13 May 2024 23:06:45 +0800 Message-ID: <1715611933.2264705-1-hengqi@linux.alibaba.com> Subject: Re: [PATCH net-next v13 2/4] ethtool: provide customized dim profile management Date: Mon, 13 May 2024 22:52:13 +0800 From: Heng Qi To: Jakub Kicinski Cc: kernel test robot , llvm@lists.linux.dev, oe-kbuild-all@lists.linux.dev, "David S . Miller" , Paolo Abeni , Eric Dumazet , Jason Wang , "Michael S . Tsirkin" , Brett Creeley , Ratheesh Kannoth , Alexander Lobakin , Xuan Zhuo , Tal Gilboa , Jonathan Corbet , linux-doc@vger.kernel.org, Maxime Chevallier , Jiri Pirko , Paul Greenwalt , Ahmed Zaki , Vladimir Oltean , Kory Maincent , Andrew Lunn , justinstitt@google.com, donald.hunter@gmail.com, netdev@vger.kernel.org, virtualization@lists.linux.dev References: <20240509044747.101237-1-hengqi@linux.alibaba.com> <20240509044747.101237-3-hengqi@linux.alibaba.com> <202405100654.5PbLQXnL-lkp@intel.com> <1715531818.6973832-3-hengqi@linux.alibaba.com> <20240513072249.7b0513b0@kernel.org> In-Reply-To: <20240513072249.7b0513b0@kernel.org> Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: On Mon, 13 May 2024 07:22:49 -0700, Jakub Kicinski wrote: > On Mon, 13 May 2024 00:36:58 +0800 Heng Qi wrote: > > This failed use case seems to come from this series triggering a problem that > > has not been triggered historically, namely lockdep_rtnl_is_held() is not called > > in an environment where CONFIG_NET is not configured and CONFIG_PROVE_LOCKING is > > configured: > > If CONFIG_PROVE_LOCKING is configured as Y and CONFIG_NET is n, then > > lockdep_rtnl_is_held is in an undefined state at this time. > > > > So I think we should declare "CONFIG_PROVE_LOCKING depends on CONFIG_NET". > > How do you think? > > Doesn't sound right, `can we instead make building lib/dim/net_dim.c Why? IIUC, the reason is that if CONFIG_NET is not set to Y, the net/core directory will not be compiled, so the lockdep_rtnl_is_held symbol is not present. > dependent on CONFIG_NET? Untested but I'm thinking something like: > > diff --git a/lib/dim/Makefile b/lib/dim/Makefile > index c4cc4026c451..c02c306e2975 100644 > --- a/lib/dim/Makefile > +++ b/lib/dim/Makefile > @@ -4,4 +4,8 @@ > > obj-$(CONFIG_DIMLIB) += dimlib.o > > -dimlib-objs := dim.o net_dim.o rdma_dim.o > +dimlib-objs := dim.o rdma_dim.o > + > +ifeq ($(CONFIG_NET),y) > +dimlib-objs += net_dim.o > +endif 1. This is unlikely to work if the kernel is configured as[1]: [1] kernel configuration CONFIG_NET=n, CONFIG_ETHTOOL_NETLINK=n, CONFIG_PROVE_LOCKING=y, (CONFIG_FSL_MC_DPIO=y && CONFIG_FSL_MC_BUS=y) select CONFIG_DIMLIB=y. Then, because CONFIG_NET is not enabled, so there is no net_dim.o, the following warning appears: ld.lld: error: undefined symbol: net_dim_get_rx_moderation referenced by dpio-service.c drivers/soc/fsl/dpio/dpio-service.o:(dpaa2_io_dim_work) in archive vmlinux.a ld.lld: error: undefined symbol: net_dim referenced by dpio-service.c drivers/soc/fsl/dpio/dpio-service.o:(dpaa2_io_update_net_dim) in archive vmlinux.a 2. If we declare "CONFIG_DIMLIB depends on CONFIG_NET", if the configuration is still [1]: Then the result is: CONFIG_DIMLIB=Y (selected by CONFIG_FSL_MC_DPIO=y && CONFIG_FSL_MC_BUS=y), CONFIG_NET=n, but we declared "CONFIG_DIMLIB depends on CONFIG_NET", there is still a compilation error because the lockdep_rtnl_is_held symbol cannot be found. 3. If we declare "CONFIG_DIMLIB select CONFIG_NET" and kernel configuration is [1], then a circular dependency warning will appear: CONFIG_DIMLIB select CONFIG_NET, ETHTOOL_NETLINK=Y(depends on CONFIG_NET) selects CONFIG_DIMLIB. CONFIG_DIMLIB will select CONFIG_NET... > >