2024-05-27 10:11:32

by kernel test robot

[permalink] [raw]
Subject: drivers/tty/mxser.c:291:2: warning: 'counted_by' should not be applied to an array with element of unknown size because 'struct mxser_port' is a struct type with a flexible array member. This will be an error in a future compiler version

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 1613e604df0cd359cf2a7fbd9be7a0bcfacfabd0
commit: f34907ecca71177a438bc1f1012e945326f707c3 mxser: Annotate struct mxser_board with __counted_by
date: 8 months ago
config: s390-randconfig-002-20240527 (https://download.01.org/0day-ci/archive/20240527/[email protected]/config)
compiler: clang version 19.0.0git (https://github.com/llvm/llvm-project 7aa382fd7257d9bd4f7fc50bb7078a3c26a1628c)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240527/[email protected]/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 <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/

All warnings (new ones prefixed by >>):

In file included from drivers/tty/mxser.c:18:
In file included from include/linux/module.h:19:
In file included from include/linux/elf.h:6:
In file included from arch/s390/include/asm/elf.h:173:
In file included from arch/s390/include/asm/mmu_context.h:11:
In file included from arch/s390/include/asm/pgalloc.h:18:
In file included from include/linux/mm.h:2168:
include/linux/vmstat.h:522:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
522 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
| ~~~~~~~~~~~ ^ ~~~
In file included from drivers/tty/mxser.c:24:
In file included from include/linux/tty.h:12:
In file included from include/linux/tty_port.h:5:
In file included from include/linux/kfifo.h:42:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
547 | val = __raw_readb(PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
560 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:37:59: note: expanded from macro '__le16_to_cpu'
37 | #define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x))
| ^
include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16'
102 | #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
| ^
In file included from drivers/tty/mxser.c:24:
In file included from include/linux/tty.h:12:
In file included from include/linux/tty_port.h:5:
In file included from include/linux/kfifo.h:42:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
573 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:35:59: note: expanded from macro '__le32_to_cpu'
35 | #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
| ^
include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32'
115 | #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
| ^
In file included from drivers/tty/mxser.c:24:
In file included from include/linux/tty.h:12:
In file included from include/linux/tty_port.h:5:
In file included from include/linux/kfifo.h:42:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
584 | __raw_writeb(value, PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
594 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
604 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:692:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
692 | readsb(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:700:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
700 | readsw(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:708:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
708 | readsl(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:717:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
717 | writesb(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:726:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
726 | writesw(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:735:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
735 | writesl(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
>> drivers/tty/mxser.c:291:2: warning: 'counted_by' should not be applied to an array with element of unknown size because 'struct mxser_port' is a struct type with a flexible array member. This will be an error in a future compiler version [-Wbounds-safety-counted-by-elt-type-unknown-size]
291 | struct mxser_port ports[] __counted_by(nports);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
14 warnings generated.


vim +291 drivers/tty/mxser.c

281
282 struct mxser_board {
283 unsigned int idx;
284 unsigned short nports;
285 int irq;
286 unsigned long vector;
287
288 enum mxser_must_hwid must_hwid;
289 speed_t max_baud;
290
> 291 struct mxser_port ports[] __counted_by(nports);
292 };
293

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