tree: git://git.infradead.org/users/hch/misc.git dma-header-cleanups head: 5093be553444b2cc6c459d6e9f5a4692ac0b4125 commit: 66216ba208594466fc57ef598198a7821a995ea0 [23/31] dma-mapping: split <linux/dma-mapping.h> config: x86_64-randconfig-s022-20200911 (attached as .config) compiler: gcc-9 (Debian 9.3.0-15) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.2-191-g10164920-dirty git checkout 66216ba208594466fc57ef598198a7821a995ea0 # save the attached .config to linux build tree make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): arch/x86/xen/pci-swiotlb-xen.c: In function 'pci_xen_swiotlb_init': 63 | dma_ops = &xen_swiotlb_dma_ops; | ^~~~~~~ | smp_ops arch/x86/xen/pci-swiotlb-xen.c:63:3: note: each undeclared identifier is reported only once for each function it appears in arch/x86/xen/pci-swiotlb-xen.c: In function 'pci_xen_swiotlb_init_late': arch/x86/xen/pci-swiotlb-xen.c:83:2: error: 'dma_ops' undeclared (first use in this function); did you mean 'smp_ops'? 83 | dma_ops = &xen_swiotlb_dma_ops; | ^~~~~~~ | smp_ops git remote add hch-misc git://git.infradead.org/users/hch/misc.git git fetch --no-tags hch-misc dma-header-cleanups git checkout 66216ba208594466fc57ef598198a7821a995ea0 vim +63 arch/x86/xen/pci-swiotlb-xen.c bbbe57386e857e Konrad Rzeszutek Wilk 2010-02-09 58 bbbe57386e857e Konrad Rzeszutek Wilk 2010-02-09 59 void __init pci_xen_swiotlb_init(void) bbbe57386e857e Konrad Rzeszutek Wilk 2010-02-09 60 { bbbe57386e857e Konrad Rzeszutek Wilk 2010-02-09 61 if (xen_swiotlb) { b8277600536989 Konrad Rzeszutek Wilk 2012-08-23 62 xen_swiotlb_init(1, true /* early */); bbbe57386e857e Konrad Rzeszutek Wilk 2010-02-09 @63 dma_ops = &xen_swiotlb_dma_ops; 74226b8c8a0b10 Konrad Rzeszutek Wilk 2010-08-19 64 :::::: The code at line 63 was first introduced by commit :::::: bbbe57386e857eb2a8d4abcae71063c819c06ff1 pci-swiotlb-xen: Add glue code to setup dma_ops utilizing xen_swiotlb_* functions. :::::: TO: Konrad Rzeszutek Wilk <konrad.wilk(a)oracle.com&gt; :::::: CC: Konrad Rzeszutek Wilk <konrad.wilk(a)oracle.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org