tree: https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git for-next head: 6d4150dd565ad788d6ee6c327ef0e8c4ad1a6d2a commit: 8d62fe051cff68c21d584898e8a521e76178f69c [17/18] Merge branch 'io_uring-5.12' into for-next config: s390-randconfig-r013-20210411 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 9829f5e6b1bca9b61efc629770d28bb9014dec45) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install s390 cross compiling tool for clang build # apt-get install binutils-s390x-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git/com... git remote add block https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git git fetch --no-tags block for-next git checkout 8d62fe051cff68c21d584898e8a521e76178f69c # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=s390 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 >>): In file included from fs/io_uring.c:60: In file included from include/linux/blkdev.h:26: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:80: include/asm-generic/io.h:464:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __raw_readb(PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:477:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr)); ~~~~~~~~~~ ^ include/uapi/linux/byteorder/big_endian.h:36:59: note: expanded from macro '__le16_to_cpu' #define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x)) ^ include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16' #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x)) ^ In file included from fs/io_uring.c:60: In file included from include/linux/blkdev.h:26: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:80: include/asm-generic/io.h:490:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr)); ~~~~~~~~~~ ^ include/uapi/linux/byteorder/big_endian.h:34:59: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x)) ^ include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32' #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x)) ^ In file included from fs/io_uring.c:60: In file included from include/linux/blkdev.h:26: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:80: include/asm-generic/io.h:501:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writeb(value, PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:511:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:521:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:609:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsb(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:617:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsw(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:625:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsl(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:634:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesb(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:643:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesw(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:652:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesl(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ if (!io_rw_reissue(req)) { ^ 12 warnings and 1 error generated. vim +/io_rw_reissue +2765 fs/io_uring.c 2b188cc1bb857a Jens Axboe 2019-01-07 2740 a1d7c393c4711a Jens Axboe 2020-06-22 2741 static void kiocb_done(struct kiocb *kiocb, ssize_t ret, 889fca73287b0a Pavel Begunkov 2021-02-10 2742 unsigned int issue_flags) ba816ad61fdf31 Jens Axboe 2019-09-28 2743 { ba04291eb66ed8 Jens Axboe 2019-12-25 2744 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb); e8c2bc1fb6c949 Jens Axboe 2020-08-15 2745 struct io_async_rw *io = req->async_data; 9728463737db02 Pavel Begunkov 2021-04-08 2746 bool check_reissue = kiocb->ki_complete == io_complete_rw; ba04291eb66ed8 Jens Axboe 2019-12-25 2747 227c0c9673d867 Jens Axboe 2020-08-13 2748 /* add previously done IO, if any */ e8c2bc1fb6c949 Jens Axboe 2020-08-15 2749 if (io && io->bytes_done > 0) { 227c0c9673d867 Jens Axboe 2020-08-13 2750 if (ret < 0) e8c2bc1fb6c949 Jens Axboe 2020-08-15 2751 ret = io->bytes_done; 227c0c9673d867 Jens Axboe 2020-08-13 2752 else e8c2bc1fb6c949 Jens Axboe 2020-08-15 2753 ret += io->bytes_done; 227c0c9673d867 Jens Axboe 2020-08-13 2754 } 227c0c9673d867 Jens Axboe 2020-08-13 2755 ba04291eb66ed8 Jens Axboe 2019-12-25 2756 if (req->flags & REQ_F_CUR_POS) ba04291eb66ed8 Jens Axboe 2019-12-25 2757 req->file->f_pos = kiocb->ki_pos; bcaec089c5b649 Pavel Begunkov 2020-02-24 2758 if (ret >= 0 && kiocb->ki_complete == io_complete_rw) 889fca73287b0a Pavel Begunkov 2021-02-10 2759 __io_complete_rw(req, ret, 0, issue_flags); ba816ad61fdf31 Jens Axboe 2019-09-28 2760 else ba816ad61fdf31 Jens Axboe 2019-09-28 2761 io_rw_done(kiocb, ret); 9728463737db02 Pavel Begunkov 2021-04-08 2762 9728463737db02 Pavel Begunkov 2021-04-08 2763 if (check_reissue && req->flags & REQ_F_REISSUE) { 9728463737db02 Pavel Begunkov 2021-04-08 2764 req->flags &= ~REQ_F_REISSUE; 9728463737db02 Pavel Begunkov 2021-04-08 @2765 if (!io_rw_reissue(req)) { 9728463737db02 Pavel Begunkov 2021-04-08 2766 int cflags = 0; 9728463737db02 Pavel Begunkov 2021-04-08 2767 9728463737db02 Pavel Begunkov 2021-04-08 2768 req_set_fail_links(req); 9728463737db02 Pavel Begunkov 2021-04-08 2769 if (req->flags & REQ_F_BUFFER_SELECTED) 9728463737db02 Pavel Begunkov 2021-04-08 2770 cflags = io_put_rw_kbuf(req); 9728463737db02 Pavel Begunkov 2021-04-08 2771 __io_req_complete(req, issue_flags, ret, cflags); 9728463737db02 Pavel Begunkov 2021-04-08 2772 } 9728463737db02 Pavel Begunkov 2021-04-08 2773 } ba816ad61fdf31 Jens Axboe 2019-09-28 2774 } ba816ad61fdf31 Jens Axboe 2019-09-28 2775 :::::: The code at line 2765 was first introduced by commit :::::: 9728463737db027557e8ba315cbbca6b81122c04 io_uring: fix rw req completion :::::: TO: Pavel Begunkov <asml.silence(a)gmail.com&gt; :::::: CC: Jens Axboe <axboe(a)kernel.dk&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org