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 0E7A62D05C; Mon, 27 Nov 2023 23:02:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="I8C5RHR6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 33008C433C7; Mon, 27 Nov 2023 23:02:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1701126148; bh=YLLMZKQjdvs7uz96PPE8o23RNDSBJoI1RZLjOJeLQMI=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=I8C5RHR6EFDKcBVX3nje6O6EJvUbNDCsMTBoso5bENtaBBA1jHF0aQZtI6JtptfiE wo1Nwx4a3wkB5Mi05gtOh2NWro+X3ZUmpR46MNx4iopyoB7z+XjnMdw25yaAeC7rvU sX5l9pl7+vJ8u1vY/3N1ovxT3baJP/HSyAsnXPBqVv4uthCy2j75YxoxZYU5FMkrM/ 648PCIzkaRri7Ar+DZyGpZV4ERXtvoA5hhY8V8Mr1lV94pXuDcNAHRj5fRSyTtWE8b uAA5Bt0WBhz4TmoIGGlRFWI0soZMvWE11aAlwrc/axPfbOxx3DC57vT8cHXl9NfnTA oSzQDKtJAuLIw== Date: Tue, 28 Nov 2023 08:02:23 +0900 From: Masami Hiramatsu (Google) To: kernel test robot Cc: linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org, oe-kbuild-all@lists.linux.dev, JP Kobryn , bpf@vger.kernel.org, kernel-team@meta.com, rostedt@goodmis.org, peterz@infradead.org Subject: Re: [PATCH] rethook: Use __rcu pointer for rethook::handler Message-Id: <20231128080223.2c0bfdbe0738983b38250333@kernel.org> In-Reply-To: <202311241808.rv9ceuAh-lkp@intel.com> References: <170078778632.209874.7893551840863388753.stgit@devnote2> <202311241808.rv9ceuAh-lkp@intel.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Fri, 24 Nov 2023 23:40:57 +0800 kernel test robot wrote: > Hi Masami, > > kernel test robot noticed the following build warnings: > > [auto build test WARNING on linus/master] > [also build test WARNING on v6.7-rc2 next-20231124] > [If your patch is applied to the wrong git tree, kindly drop us a note. > And when submitting patch, we suggest to use '--base' as documented in > https://git-scm.com/docs/git-format-patch#_base_tree_information] > > url: https://github.com/intel-lab-lkp/linux/commits/Masami-Hiramatsu-Google/rethook-Use-__rcu-pointer-for-rethook-handler/20231124-090634 > base: linus/master > patch link: https://lore.kernel.org/r/170078778632.209874.7893551840863388753.stgit%40devnote2 > patch subject: [PATCH] rethook: Use __rcu pointer for rethook::handler > config: x86_64-randconfig-r113-20231124 (https://download.01.org/0day-ci/archive/20231124/202311241808.rv9ceuAh-lkp@intel.com/config) > compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07) > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231124/202311241808.rv9ceuAh-lkp@intel.com/reproduce) Let me fix this issue. It seems that sparse with function pointer needs a special care. Thank you, > > If you fix the issue in a separate patch/commit (i.e. not just a new version of > the same patch/commit), kindly add following tags > | Reported-by: kernel test robot > | Closes: https://lore.kernel.org/oe-kbuild-all/202311241808.rv9ceuAh-lkp@intel.com/ > > sparse warnings: (new ones prefixed by >>) > >> kernel/trace/rethook.c:51:9: sparse: sparse: incompatible types in comparison expression (different address spaces): > >> kernel/trace/rethook.c:51:9: sparse: void ( [noderef] __rcu * )( ... ) > >> kernel/trace/rethook.c:51:9: sparse: void ( * )( ... ) > kernel/trace/rethook.c:66:9: sparse: sparse: incompatible types in comparison expression (different address spaces): > kernel/trace/rethook.c:66:9: sparse: void ( [noderef] __rcu * )( ... ) > kernel/trace/rethook.c:66:9: sparse: void ( * )( ... ) > kernel/trace/rethook.c:110:9: sparse: sparse: incompatible types in comparison expression (different address spaces): > kernel/trace/rethook.c:110:9: sparse: void ( [noderef] __rcu * )( ... ) > kernel/trace/rethook.c:110:9: sparse: void ( * )( ... ) > kernel/trace/rethook.c:140:19: sparse: sparse: incompatible types in comparison expression (different address spaces): > kernel/trace/rethook.c:140:19: sparse: void ( [noderef] __rcu * )( ... ) > kernel/trace/rethook.c:140:19: sparse: void ( * )( ... ) > kernel/trace/rethook.c:161:19: sparse: sparse: incompatible types in comparison expression (different address spaces): > kernel/trace/rethook.c:161:19: sparse: void ( [noderef] __rcu * )( ... ) > kernel/trace/rethook.c:161:19: sparse: void ( * )( ... ) > kernel/trace/rethook.c:305:27: sparse: sparse: incompatible types in comparison expression (different address spaces): > kernel/trace/rethook.c:305:27: sparse: void ( [noderef] __rcu * )( ... ) > kernel/trace/rethook.c:305:27: sparse: void ( * )( ... ) > > vim +51 kernel/trace/rethook.c > > 40 > 41 /** > 42 * rethook_stop() - Stop using a rethook. > 43 * @rh: the struct rethook to stop. > 44 * > 45 * Stop using a rethook to prepare for freeing it. If you want to wait for > 46 * all running rethook handler before calling rethook_free(), you need to > 47 * call this first and wait RCU, and call rethook_free(). > 48 */ > 49 void rethook_stop(struct rethook *rh) > 50 { > > 51 rcu_assign_pointer(rh->handler, NULL); > 52 } > 53 > > -- > 0-DAY CI Kernel Test Service > https://github.com/intel/lkp-tests/wiki -- Masami Hiramatsu (Google)