Messages in this thread | | | Date | Tue, 19 Mar 2024 12:45:36 +0800 | From | kernel test robot <> | Subject | Re: [PATCH v2 1/2] swiotlb: extend buffer pre-padding to alloc_align_mask if necessary |
| |
Hi Petr,
kernel test robot noticed the following build warnings:
[auto build test WARNING on v6.8] [also build test WARNING on linus/master next-20240318] [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/Petr-Tesarik/swiotlb-extend-buffer-pre-padding-to-alloc_align_mask-if-necessary/20240318-212500 base: v6.8 patch link: https://lore.kernel.org/r/20240318130447.594-2-petrtesarik%40huaweicloud.com patch subject: [PATCH v2 1/2] swiotlb: extend buffer pre-padding to alloc_align_mask if necessary config: s390-allnoconfig (https://download.01.org/0day-ci/archive/20240319/202403191203.AtV7fvue-lkp@intel.com/config) compiler: clang version 19.0.0git (https://github.com/llvm/llvm-project 8f68022f8e6e54d1aeae4ed301f5a015963089b7) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240319/202403191203.AtV7fvue-lkp@intel.com/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@intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202403191203.AtV7fvue-lkp@intel.com/
All warnings (new ones prefixed by >>):
In file included from kernel/dma/swiotlb.c:27: In file included from include/linux/dma-direct.h:9: In file included from include/linux/dma-mapping.h:8: In file included from include/linux/device.h:32: In file included from include/linux/device/driver.h:21: 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:2188: 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 kernel/dma/swiotlb.c:27: In file included from include/linux/dma-direct.h:9: In file included from include/linux/dma-mapping.h:11: 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 kernel/dma/swiotlb.c:27: In file included from include/linux/dma-direct.h:9: In file included from include/linux/dma-mapping.h:11: 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 kernel/dma/swiotlb.c:27: In file included from include/linux/dma-direct.h:9: In file included from include/linux/dma-mapping.h:11: 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); | ~~~~~~~~~~ ^ >> kernel/dma/swiotlb.c:1348:33: warning: variable 'i' is uninitialized when used here [-Wuninitialized] 1348 | pool->slots[index].pad_slots = i; | ^ kernel/dma/swiotlb.c:1301:16: note: initialize the variable 'i' to silence this warning 1301 | unsigned int i; | ^ | = 0 kernel/dma/swiotlb.c:1643:20: warning: unused function 'swiotlb_create_debugfs_files' [-Wunused-function] 1643 | static inline void swiotlb_create_debugfs_files(struct io_tlb_mem *mem, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ 15 warnings generated.
vim +/i +1348 kernel/dma/swiotlb.c
1292 1293 phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, 1294 size_t mapping_size, size_t alloc_size, 1295 unsigned int alloc_align_mask, enum dma_data_direction dir, 1296 unsigned long attrs) 1297 { 1298 struct io_tlb_mem *mem = dev->dma_io_tlb_mem; 1299 unsigned int offset; 1300 struct io_tlb_pool *pool; 1301 unsigned int i; 1302 int index; 1303 phys_addr_t tlb_addr; 1304 unsigned short pad_slots; 1305 1306 if (!mem || !mem->nslabs) { 1307 dev_warn_ratelimited(dev, 1308 "Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer"); 1309 return (phys_addr_t)DMA_MAPPING_ERROR; 1310 } 1311 1312 if (cc_platform_has(CC_ATTR_MEM_ENCRYPT)) 1313 pr_warn_once("Memory encryption is active and system is using DMA bounce buffers\n"); 1314 1315 if (mapping_size > alloc_size) { 1316 dev_warn_once(dev, "Invalid sizes (mapping: %zd bytes, alloc: %zd bytes)", 1317 mapping_size, alloc_size); 1318 return (phys_addr_t)DMA_MAPPING_ERROR; 1319 } 1320 1321 /* 1322 * Calculate buffer pre-padding within the allocated space. Use it to 1323 * preserve the low bits of the original address according to device's 1324 * min_align_mask. Limit the padding to alloc_align_mask or slot size 1325 * (whichever is bigger); higher bits of the original address are 1326 * preserved by selecting a suitable IO TLB slot. 1327 */ 1328 offset = orig_addr & dma_get_min_align_mask(dev) & 1329 (alloc_align_mask | (IO_TLB_SIZE - 1)); 1330 index = swiotlb_find_slots(dev, orig_addr, 1331 alloc_size + offset, alloc_align_mask, &pool); 1332 if (index == -1) { 1333 if (!(attrs & DMA_ATTR_NO_WARN)) 1334 dev_warn_ratelimited(dev, 1335 "swiotlb buffer is full (sz: %zd bytes), total %lu (slots), used %lu (slots)\n", 1336 alloc_size, mem->nslabs, mem_used(mem)); 1337 return (phys_addr_t)DMA_MAPPING_ERROR; 1338 } 1339 1340 /* 1341 * Save away the mapping from the original address to the DMA address. 1342 * This is needed when we sync the memory. Then we sync the buffer if 1343 * needed. 1344 */ 1345 pad_slots = offset / IO_TLB_SIZE; 1346 offset %= IO_TLB_SIZE; 1347 index += pad_slots; > 1348 pool->slots[index].pad_slots = i; 1349 for (i = 0; i < nr_slots(alloc_size + offset); i++) 1350 pool->slots[index + i].orig_addr = slot_addr(orig_addr, i); 1351 tlb_addr = slot_addr(pool->start, index) + offset; 1352 /* 1353 * When the device is writing memory, i.e. dir == DMA_FROM_DEVICE, copy 1354 * the original buffer to the TLB buffer before initiating DMA in order 1355 * to preserve the original's data if the device does a partial write, 1356 * i.e. if the device doesn't overwrite the entire buffer. Preserving 1357 * the original data, even if it's garbage, is necessary to match 1358 * hardware behavior. Use of swiotlb is supposed to be transparent, 1359 * i.e. swiotlb must not corrupt memory by clobbering unwritten bytes. 1360 */ 1361 swiotlb_bounce(dev, tlb_addr, mapping_size, DMA_TO_DEVICE); 1362 return tlb_addr; 1363 } 1364
-- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
| |