net/core/dev.c:10290:18: sparse: sparse: cast removes address space '__percpu' of expression

From: kernel test robot <lkp@intel.com>
To: Eric Dumazet <edumazet@google.com>
Cc: kbuild-all@lists.01.org, linux-kernel@vger.kernel.org,
	Jakub Kicinski <kuba@kernel.org>,
	Brian Vazquez <brianvv@google.com>
Subject: net/core/dev.c:10290:18: sparse: sparse: cast removes address space '__percpu' of expression
Date: Wed, 13 Jul 2022 23:48:45 +0800	[thread overview]
Message-ID: <202207132315.QFxcZZNI-lkp@intel.com> (raw)

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   b047602d579b4fb028128a525f056bbdc890e7f0
commit: 625788b5844511cf4c30cffa7fa0bc3a69cebc82 net: add per-cpu storage and net->core_stats
date:   4 months ago
config: riscv-randconfig-s032-20220713 (https://download.01.org/0day-ci/archive/20220713/202207132315.QFxcZZNI-lkp@intel.com/config)
compiler: riscv32-linux-gcc (GCC) 11.3.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # apt-get install sparse
        # sparse version: v0.6.4-39-gce1a6720-dirty
        # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=625788b5844511cf4c30cffa7fa0bc3a69cebc82
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout 625788b5844511cf4c30cffa7fa0bc3a69cebc82
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=riscv SHELL=/bin/bash net/core/

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>


sparse warnings: (new ones prefixed by >>)
   net/core/dev.c:3254:23: sparse: sparse: incorrect type in argument 4 (different base types) @@     expected restricted __wsum [usertype] csum @@     got unsigned int @@
   net/core/dev.c:3254:23: sparse:     expected restricted __wsum [usertype] csum
   net/core/dev.c:3254:23: sparse:     got unsigned int
   net/core/dev.c:3254:23: sparse: sparse: cast from restricted __wsum
>> net/core/dev.c:10290:18: sparse: sparse: cast removes address space '__percpu' of expression
   net/core/dev.c:3759:17: sparse: sparse: context imbalance in '__dev_queue_xmit' - different lock contexts for basic block
   net/core/dev.c:4961:17: sparse: sparse: context imbalance in 'net_tx_action' - different lock contexts for basic block

vim +/__percpu +10290 net/core/dev.c

 10282	
 10283	struct net_device_core_stats *netdev_core_stats_alloc(struct net_device *dev)
 10284	{
 10285		struct net_device_core_stats __percpu *p;
 10286	
 10287		p = alloc_percpu_gfp(struct net_device_core_stats,
 10288				     GFP_ATOMIC | __GFP_NOWARN);
 10289	
 10290		if (p && cmpxchg(&dev->core_stats, NULL, p))
 10291			free_percpu(p);
 10292	
 10293		/* This READ_ONCE() pairs with the cmpxchg() above */
 10294		p = READ_ONCE(dev->core_stats);
 10295		if (!p)
 10296			return NULL;
 10297	
 10298		return this_cpu_ptr(p);
 10299	}
 10300	EXPORT_SYMBOL(netdev_core_stats_alloc);
 10301	

-- 
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