Date:   Thu, 2 Feb 2023 01:31:42 +0800
From:   kernel test robot <lkp@intel.com>
To:     Logan Gunthorpe <logang@deltatee.com>
Cc:     oe-kbuild-all@lists.linux.dev, linux-kernel@vger.kernel.org,
        Jens Axboe <axboe@kernel.dk>, Christoph Hellwig <hch@lst.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Chaitanya Kulkarni <kch@nvidia.com>
Subject: drivers/pci/p2pdma.c:199:44: sparse: sparse: dereference of noderef
 expression
Message-ID: <202302020153.4eL3mwiK-lkp@intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Precedence: bulk

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   c0b67534c95c537f7a506a06b98e5e85d72e2b7d
commit: 7e9c7ef83d785236f5a8c3761dd053fae9b92fb8 PCI/P2PDMA: Allow userspace VMA allocations through sysfs
date:   3 months ago
config: arm64-randconfig-s042-20230201 (https://download.01.org/0day-ci/archive/20230202/202302020153.4eL3mwiK-lkp@intel.com/config)
compiler: aarch64-linux-gcc (GCC) 12.1.0
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=7e9c7ef83d785236f5a8c3761dd053fae9b92fb8
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout 7e9c7ef83d785236f5a8c3761dd053fae9b92fb8
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=arm64 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=arm64 SHELL=/bin/bash drivers/pci/

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 >>)
>> drivers/pci/p2pdma.c:199:44: sparse: sparse: dereference of noderef expression

vim +199 drivers/pci/p2pdma.c

   193	
   194	static void p2pdma_page_free(struct page *page)
   195	{
   196		struct pci_p2pdma_pagemap *pgmap = to_p2p_pgmap(page->pgmap);
   197		struct percpu_ref *ref;
   198	
 > 199		gen_pool_free_owner(pgmap->provider->p2pdma->pool,
   200				    (uintptr_t)page_to_virt(page), PAGE_SIZE,
   201				    (void **)&ref);
   202		percpu_ref_put(ref);
   203	}
   204	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests