tree: git://git.infradead.org/users/hch/misc.git swiotlb-fix head: b312f891c5bef58d2d3b287fd3ac90abe1588192 commit: 4a32ebd5ef3f301848088178b7452a4ec9c9ccea [9/10] wip config: s390-randconfig-r022-20210510 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 492173d42b32cb91d5d0d72d5ed84fcab80d059a) 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 git remote add hch-misc git://git.infradead.org/users/hch/misc.git git fetch --no-tags hch-misc swiotlb-fix git checkout 4a32ebd5ef3f301848088178b7452a4ec9c9ccea # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 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 kernel/dma/swiotlb.c:24: In file included from include/linux/dma-direct.h:9: In file included from include/linux/dma-mapping.h:10: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:75: 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 kernel/dma/swiotlb.c:24: In file included from include/linux/dma-direct.h:9: In file included from include/linux/dma-mapping.h:10: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:75: 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 kernel/dma/swiotlb.c:24: In file included from include/linux/dma-direct.h:9: In file included from include/linux/dma-mapping.h:10: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:75: 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); ~~~~~~~~~~ ^ In file included from kernel/dma/swiotlb.c:51: #include <trace/define_trace.h> ^ include/trace/events/swiotlb.h:10:1: note: expansion of macro 'TRACE_EVENT' requested here TRACE_EVENT(swiotlb_bounced, ^ TRACE_EVENT(swiotlb_bounced, ^ include/linux/tracepoint.h:542:9: note: macro 'TRACE_EVENT' defined here #define TRACE_EVENT(name, proto, args, struct, assign, print) \ ^ 12 warnings and 2 errors generated. vim +49 include/trace/events/swiotlb.h 2b2b614dd24e4e Zoltan Kiss 2013-09-04 9 2b2b614dd24e4e Zoltan Kiss 2013-09-04 @10 TRACE_EVENT(swiotlb_bounced, 2b2b614dd24e4e Zoltan Kiss 2013-09-04 11 2b2b614dd24e4e Zoltan Kiss 2013-09-04 12 TP_PROTO(struct device *dev, 2b2b614dd24e4e Zoltan Kiss 2013-09-04 13 dma_addr_t dev_addr, 2b2b614dd24e4e Zoltan Kiss 2013-09-04 14 size_t size, ae7871be189cb4 Geert Uytterhoeven 2016-12-16 15 enum swiotlb_force swiotlb_force), 2b2b614dd24e4e Zoltan Kiss 2013-09-04 16 2b2b614dd24e4e Zoltan Kiss 2013-09-04 17 TP_ARGS(dev, dev_addr, size, swiotlb_force), 2b2b614dd24e4e Zoltan Kiss 2013-09-04 18 2b2b614dd24e4e Zoltan Kiss 2013-09-04 19 TP_STRUCT__entry( 2b2b614dd24e4e Zoltan Kiss 2013-09-04 20 __string( dev_name, dev_name(dev) ) 2b2b614dd24e4e Zoltan Kiss 2013-09-04 21 __field( u64, dma_mask ) 2b2b614dd24e4e Zoltan Kiss 2013-09-04 22 __field( dma_addr_t, dev_addr ) 2b2b614dd24e4e Zoltan Kiss 2013-09-04 23 __field( size_t, size ) ae7871be189cb4 Geert Uytterhoeven 2016-12-16 24 __field( enum swiotlb_force, swiotlb_force ) 2b2b614dd24e4e Zoltan Kiss 2013-09-04 25 ), 2b2b614dd24e4e Zoltan Kiss 2013-09-04 26 2b2b614dd24e4e Zoltan Kiss 2013-09-04 27 TP_fast_assign( 2b2b614dd24e4e Zoltan Kiss 2013-09-04 28 __assign_str(dev_name, dev_name(dev)); 2b2b614dd24e4e Zoltan Kiss 2013-09-04 29 __entry->dma_mask = (dev->dma_mask ? *dev->dma_mask : 0); 2b2b614dd24e4e Zoltan Kiss 2013-09-04 30 __entry->dev_addr = dev_addr; 2b2b614dd24e4e Zoltan Kiss 2013-09-04 31 __entry->size = size; 2b2b614dd24e4e Zoltan Kiss 2013-09-04 32 __entry->swiotlb_force = swiotlb_force; 2b2b614dd24e4e Zoltan Kiss 2013-09-04 33 ), 2b2b614dd24e4e Zoltan Kiss 2013-09-04 34 2b2b614dd24e4e Zoltan Kiss 2013-09-04 35 TP_printk("dev_name: %s dma_mask=%llx dev_addr=%llx " 2b2b614dd24e4e Zoltan Kiss 2013-09-04 36 "size=%zu %s", 2b2b614dd24e4e Zoltan Kiss 2013-09-04 37 __get_str(dev_name), 2b2b614dd24e4e Zoltan Kiss 2013-09-04 38 __entry->dma_mask, 2b2b614dd24e4e Zoltan Kiss 2013-09-04 39 (unsigned long long)__entry->dev_addr, 2b2b614dd24e4e Zoltan Kiss 2013-09-04 40 __entry->size, ae7871be189cb4 Geert Uytterhoeven 2016-12-16 41 __print_symbolic(__entry->swiotlb_force, ae7871be189cb4 Geert Uytterhoeven 2016-12-16 42 { SWIOTLB_NORMAL, "NORMAL" }, fff5d99225107f Geert Uytterhoeven 2016-12-16 43 { SWIOTLB_FORCE, "FORCE" }, 2b2b614dd24e4e Zoltan Kiss 2013-09-04 44 ); 2b2b614dd24e4e Zoltan Kiss 2013-09-04 45 2b2b614dd24e4e Zoltan Kiss 2013-09-04 46 #endif /* _TRACE_SWIOTLB_H */ 2b2b614dd24e4e Zoltan Kiss 2013-09-04 47 2b2b614dd24e4e Zoltan Kiss 2013-09-04 48 /* This part must be outside protection */ 2b2b614dd24e4e Zoltan Kiss 2013-09-04 @49 #include <trace/define_trace.h> :::::: The code at line 49 was first introduced by commit :::::: 2b2b614dd24e4e6474fcf2dcf69c95c908838959 tracing/events: Add bounce tracing to swiotbl :::::: TO: Zoltan Kiss <zoltan.kiss(a)citrix.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