tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: f81e94e91878bded599cc60f2881cfd50991aeb9 commit: edad96db58d2f0b666ddd0a3e0f179e586f5f66a [2984/3632] iommu/vt-d: Fix unmap_pages support config: x86_64-buildonly-randconfig-r004-20211126 (https://download.01.org/0day-ci/archive/20211126/202111260939.DmjPLz34-lkp@xxxxxxxxx/config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 0332d105b9ad7f1f0ffca7e78b71de8b3a48f158) 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 # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=edad96db58d2f0b666ddd0a3e0f179e586f5f66a git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git fetch --no-tags linux-next master git checkout edad96db58d2f0b666ddd0a3e0f179e586f5f66a # save the config file to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> drivers/iommu/intel/iommu.c:1344:7: warning: variable 'level_pfn' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] if (!dma_pte_present(pte)) ^~~~~~~~~~~~~~~~~~~~~ drivers/iommu/intel/iommu.c:1369:9: note: uninitialized use occurs here pfn = level_pfn + level_size(level); ^~~~~~~~~ drivers/iommu/intel/iommu.c:1344:3: note: remove the 'if' if its condition is always false if (!dma_pte_present(pte)) ^~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/iommu/intel/iommu.c:1342:26: note: initialize the variable 'level_pfn' to silence this warning unsigned long level_pfn; ^ = 0 drivers/iommu/intel/iommu.c:136:29: warning: unused function 'dma_to_mm_pfn' [-Wunused-function] static inline unsigned long dma_to_mm_pfn(unsigned long dma_pfn) ^ 2 warnings generated. vim +1344 drivers/iommu/intel/iommu.c ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1329 ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1330 static struct page *dma_pte_clear_level(struct dmar_domain *domain, int level, ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1331 struct dma_pte *pte, unsigned long pfn, ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1332 unsigned long start_pfn, ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1333 unsigned long last_pfn, ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1334 struct page *freelist) ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1335 { ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1336 struct dma_pte *first_pte = NULL, *last_pte = NULL; ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1337 ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1338 pfn = max(start_pfn, pfn); ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1339 pte = &pte[pfn_level_offset(pfn, level)]; ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1340 ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1341 do { ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1342 unsigned long level_pfn; ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1343 ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 @1344 if (!dma_pte_present(pte)) ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1345 goto next; ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1346 ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1347 level_pfn = pfn & level_mask(level); ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1348 ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1349 /* If range covers entire pagetable, free it */ ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1350 if (start_pfn <= level_pfn && ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1351 last_pfn >= level_pfn + level_size(level) - 1) { ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1352 /* These suborbinate page tables are going away entirely. Don't ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1353 bother to clear them; we're just going to *free* them. */ ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1354 if (level > 1 && !dma_pte_superpage(pte)) ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1355 freelist = dma_pte_list_pagetables(domain, level - 1, pte, freelist); ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1356 ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1357 dma_clear_pte(pte); ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1358 if (!first_pte) ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1359 first_pte = pte; ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1360 last_pte = pte; ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1361 } else if (level > 1) { ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1362 /* Recurse down into a level that isn't *entirely* obsolete */ ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1363 freelist = dma_pte_clear_level(domain, level - 1, ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1364 phys_to_virt(dma_pte_addr(pte)), ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1365 level_pfn, start_pfn, last_pfn, ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1366 freelist); ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1367 } ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1368 next: edad96db58d2f0b drivers/iommu/intel/iommu.c Alex Williamson 2021-11-22 1369 pfn = level_pfn + level_size(level); ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1370 } while (!first_pte_in_page(++pte) && pfn <= last_pfn); ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1371 ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1372 if (first_pte) ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1373 domain_flush_cache(domain, first_pte, ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1374 (void *)++last_pte - (void *)first_pte); ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1375 ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1376 return freelist; ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1377 } ea8ea460c9ace60 drivers/iommu/intel-iommu.c David Woodhouse 2014-03-05 1378 :::::: The code at line 1344 was first introduced by commit :::::: ea8ea460c9ace60bbb5ac6e5521d637d5c15293d iommu/vt-d: Clean up and fix page table clear/free behaviour :::::: TO: David Woodhouse <David.Woodhouse@xxxxxxxxx> :::::: CC: David Woodhouse <David.Woodhouse@xxxxxxxxx> --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
