Hi Anshuman, kernel test robot noticed the following build errors: [auto build test ERROR on char-misc/char-misc-testing] [also build test ERROR on char-misc/char-misc-next char-misc/char-misc-linus brauner-vfs/vfs.all dennis-percpu/for-next linus/master v6.11] [cannot apply to akpm-mm/mm-everything next-20240918] [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/Anshuman-Khandual/m68k-mm-Change-pmd_val/20240917-153331 base: char-misc/char-misc-testing patch link: https://lore.kernel.org/r/20240917073117.1531207-5-anshuman.khandual%40arm.com patch subject: [PATCH V2 4/7] mm: Use pmdp_get() for accessing PMD entries config: um-allnoconfig (https://download.01.org/0day-ci/archive/20240919/202409190205.YJ5gtx3T-lkp@xxxxxxxxx/config) compiler: clang version 17.0.6 (https://github.com/llvm/llvm-project 6009708b4367171ccdbf4b5905cb6a803753fe18) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240919/202409190205.YJ5gtx3T-lkp@xxxxxxxxx/reproduce) 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 <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202409190205.YJ5gtx3T-lkp@xxxxxxxxx/ All errors (new ones prefixed by >>): In file included from mm/pgtable-generic.c:10: In file included from include/linux/pagemap.h:11: In file included from include/linux/highmem.h:12: In file included from include/linux/hardirq.h:11: In file included from arch/um/include/asm/hardirq.h:5: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:14: In file included from arch/um/include/asm/io.h:24: include/asm-generic/io.h:548:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 548 | val = __raw_readb(PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:561:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 561 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu' 37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x)) | ^ In file included from mm/pgtable-generic.c:10: In file included from include/linux/pagemap.h:11: In file included from include/linux/highmem.h:12: In file included from include/linux/hardirq.h:11: In file included from arch/um/include/asm/hardirq.h:5: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:14: In file included from arch/um/include/asm/io.h:24: include/asm-generic/io.h:574:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 574 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu' 35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x)) | ^ In file included from mm/pgtable-generic.c:10: In file included from include/linux/pagemap.h:11: In file included from include/linux/highmem.h:12: In file included from include/linux/hardirq.h:11: In file included from arch/um/include/asm/hardirq.h:5: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:14: In file included from arch/um/include/asm/io.h:24: include/asm-generic/io.h:585:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 585 | __raw_writeb(value, PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:595:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 595 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:605:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 605 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:693:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 693 | readsb(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:701:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 701 | readsw(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:709:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 709 | readsl(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:718:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 718 | writesb(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:727:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 727 | writesw(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:736:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 736 | writesl(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ >> mm/pgtable-generic.c:54:2: error: cannot take the address of an rvalue of type 'pgd_t' 54 | pmd_ERROR(pmdp_get(pmd)); | ^~~~~~~~~~~~~~~~~~~~~~~~ include/asm-generic/pgtable-nopmd.h:36:28: note: expanded from macro 'pmd_ERROR' 36 | #define pmd_ERROR(pmd) (pud_ERROR((pmd).pud)) | ^~~~~~~~~~~~~~~~~~~~ include/asm-generic/pgtable-nopud.h:32:28: note: expanded from macro 'pud_ERROR' 32 | #define pud_ERROR(pud) (p4d_ERROR((pud).p4d)) | ^~~~~~~~~~~~~~~~~~~~ include/asm-generic/pgtable-nop4d.h:25:28: note: expanded from macro 'p4d_ERROR' 25 | #define p4d_ERROR(p4d) (pgd_ERROR((p4d).pgd)) | ^~~~~~~~~~~~~~~~~~~~ arch/um/include/asm/pgtable-2level.h:31:67: note: expanded from macro 'pgd_ERROR' 31 | printk("%s:%d: bad pgd %p(%08lx).\n", __FILE__, __LINE__, &(e), \ | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~ 32 | pgd_val(e)) | ~~~~~~~~~~~ include/linux/printk.h:465:60: note: expanded from macro 'printk' 465 | #define printk(fmt, ...) printk_index_wrap(_printk, fmt, ##__VA_ARGS__) | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~ include/linux/printk.h:437:19: note: expanded from macro 'printk_index_wrap' 437 | _p_func(_fmt, ##__VA_ARGS__); \ | ^~~~~~~~~~~ 12 warnings and 1 error generated. vim +/pgd_t +54 mm/pgtable-generic.c 46 47 /* 48 * Note that the pmd variant below can't be stub'ed out just as for p4d/pud 49 * above. pmd folding is special and typically pmd_* macros refer to upper 50 * level even when folded 51 */ 52 void pmd_clear_bad(pmd_t *pmd) 53 { > 54 pmd_ERROR(pmdp_get(pmd)); 55 pmd_clear(pmd); 56 } 57 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki