CC: [email protected] CC: [email protected] CC: [email protected] TO: Jakub Jelinek <[email protected]> CC: "Peter Zijlstra (Intel)" <[email protected]> CC: Andrew Morton <[email protected]> CC: Linux Memory Management List <[email protected]>
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 12119cfa1052d512a92524e90ebee85029a918f8 commit: 2f78788b55baa3410b1ec91a576286abe1ad4d6a ilog2: improve ilog2 for constant arguments date: 12 months ago :::::: branch date: 10 hours ago :::::: commit date: 12 months ago config: riscv-randconfig-c006-20211128 (https://download.01.org/0day-ci/archive/20211204/[email protected]/config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 4b553297ef3ee4dc2119d5429adf3072e90fac38) 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 riscv cross compiling tool for clang build # apt-get install binutils-riscv64-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2f78788b55baa3410b1ec91a576286abe1ad4d6a git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout 2f78788b55baa3410b1ec91a576286abe1ad4d6a # save the config file to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=riscv clang-analyzer If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <[email protected]> clang-analyzer warnings: (new ones prefixed by >>) ^~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1636:6: note: Left side of '&&' is true if (!unlocked && !dma_fence_is_signaled(vm->last_unlocked)) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1636:2: note: Taking false branch if (!unlocked && !dma_fence_is_signaled(vm->last_unlocked)) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1645:6: note: Assuming 'r' is 0 if (r) ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1645:2: note: Taking false branch if (r) ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1653:7: note: 'nodes' is null if (nodes) { ^~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1653:3: note: Taking false branch if (nodes) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1661:7: note: 'pages_addr' is null if (pages_addr) { ^~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1661:3: note: Taking false branch if (pages_addr) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1691:10: note: Taking true branch } else if (flags & (AMDGPU_PTE_VALID | AMDGPU_PTE_PRT)) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1697:7: note: Calling 'amdgpu_vm_update_ptes' r = amdgpu_vm_update_ptes(¶ms, start, tmp, addr, flags); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1442:2: note: Calling 'amdgpu_vm_fragment' amdgpu_vm_fragment(params, frag_start, end, flags, &frag, &frag_end); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1395:6: note: Assuming field 'asic_type' is >= CHIP_VEGA10 if (params->adev->asic_type < CHIP_VEGA10) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1395:2: note: Taking false branch if (params->adev->asic_type < CHIP_VEGA10) ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1401:6: note: Assuming field 'pages_addr' is non-null if (params->pages_addr) { ^~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1401:2: note: Taking true branch if (params->pages_addr) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1404:3: note: Returning without writing to 'params->unlocked', which participates in a condition later return; ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1442:2: note: Returning from 'amdgpu_vm_fragment' amdgpu_vm_fragment(params, frag_start, end, flags, &frag, &frag_end); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1446:9: note: Assuming 'end' is > field 'pfn' while (cursor.pfn < end) { ^~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1446:2: note: Loop condition is true. Entering loop body while (cursor.pfn < end) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1451:7: note: Assuming field 'unlocked' is true if (!params->unlocked) { ^~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1451:3: note: Taking false branch if (!params->unlocked) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1461:11: note: Calling 'amdgpu_vm_level_shift' shift = amdgpu_vm_level_shift(adev, cursor.level); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:125:2: note: Control jumps to the 'default' case at line 133 switch (level) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:134:3: note: Returning the value 4294967295 return ~0; ^~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1461:11: note: Returning from 'amdgpu_vm_level_shift' shift = amdgpu_vm_level_shift(adev, cursor.level); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1461:3: note: The value 4294967295 is assigned to 'shift' shift = amdgpu_vm_level_shift(adev, cursor.level); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1463:15: note: Field 'unlocked' is true if (params->unlocked) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1463:3: note: Taking true branch if (params->unlocked) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1465:8: note: Assuming the condition is false if (amdgpu_vm_pt_descendant(adev, &cursor)) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1465:4: note: Taking false branch if (amdgpu_vm_pt_descendant(adev, &cursor)) ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1492:7: note: Assuming 'pt' is non-null if (!pt) { ^~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1492:3: note: Taking false branch if (!pt) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:1510:41: note: The result of the left shift is undefined due to shifting by '4294967295', which is greater or equal to the width of type 'uint64_t' incr = (uint64_t)AMDGPU_GPU_PAGE_SIZE << shift; ^ ~~~~~ >> include/asm-generic/bitops/fls64.h:21:14: warning: The result of the '>>' >> expression is undefined [clang-analyzer-core.UndefinedBinaryOperatorResult] __u32 h = x >> 32; ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2677:6: note: Assuming the condition is true if (amdgpu_vm_size != -1) { ^~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2677:2: note: Taking true branch if (amdgpu_vm_size != -1) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2679:7: note: Assuming 'vm_size' is <= 'max_size' if (vm_size > max_size) { ^~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2679:3: note: Taking false branch if (vm_size > max_size) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2712:8: note: '?' condition is false tmp = roundup_pow_of_two(adev->vm_manager.max_pfn); ^ include/linux/log2.h:176:2: note: expanded from macro 'roundup_pow_of_two' __builtin_constant_p(n) ? ( \ ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2713:6: note: Assuming the condition is false if (amdgpu_vm_block_size != -1) ^~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2713:2: note: Taking false branch if (amdgpu_vm_block_size != -1) ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2716:31: note: Assuming '__UNIQUE_ID___x451' is >= '__UNIQUE_ID___y452' adev->vm_manager.num_level = min(max_level, (unsigned)tmp); ^ include/linux/minmax.h:51:19: note: expanded from macro 'min' #define min(x, y) __careful_cmp(x, y, <) ^~~~~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:44:3: note: expanded from macro '__careful_cmp' __cmp_once(x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y), op)) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:39:3: note: expanded from macro '__cmp_once' __cmp(unique_x, unique_y, op); }) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:34:26: note: expanded from macro '__cmp' #define __cmp(x, y, op) ((x) op (y) ? (x) : (y)) ^~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2716:31: note: '?' condition is false adev->vm_manager.num_level = min(max_level, (unsigned)tmp); ^ include/linux/minmax.h:51:19: note: expanded from macro 'min' #define min(x, y) __careful_cmp(x, y, <) ^ include/linux/minmax.h:44:3: note: expanded from macro '__careful_cmp' __cmp_once(x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y), op)) ^ include/linux/minmax.h:39:3: note: expanded from macro '__cmp_once' __cmp(unique_x, unique_y, op); }) ^ include/linux/minmax.h:34:26: note: expanded from macro '__cmp' #define __cmp(x, y, op) ((x) op (y) ? (x) : (y)) ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2717:2: note: Control jumps to the 'default' case at line 2727 switch (adev->vm_manager.num_level) { ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2731:6: note: Assuming the condition is false if (amdgpu_vm_block_size != -1) ^~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2731:2: note: Taking false branch if (amdgpu_vm_block_size != -1) ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2736:11: note: Assuming field 'num_level' is <= 1 else if (adev->vm_manager.num_level > 1) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2736:7: note: Taking false branch else if (adev->vm_manager.num_level > 1) ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2739:33: note: Calling 'amdgpu_vm_get_block_size' adev->vm_manager.block_size = amdgpu_vm_get_block_size(tmp); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2648:18: note: '?' condition is false unsigned bits = ilog2(vm_size) + 18; ^ include/linux/log2.h:158:2: note: expanded from macro 'ilog2' __builtin_constant_p(n) ? \ ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2648:18: note: '?' condition is false unsigned bits = ilog2(vm_size) + 18; ^ include/linux/log2.h:161:2: note: expanded from macro 'ilog2' (sizeof(n) <= 4) ? \ ^ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c:2648:18: note: Calling '__ilog2_u64' unsigned bits = ilog2(vm_size) + 18; ^ include/linux/log2.h:163:2: note: expanded from macro 'ilog2' __ilog2_u64(n) \ ^~~~~~~~~~~~~~ include/linux/log2.h:32:9: note: Calling 'fls64' return fls64(n) - 1; ^~~~~~~~ include/asm-generic/bitops/fls64.h:21:14: note: The result of the '>>' expression is undefined __u32 h = x >> 32; ~~^~~~~ include/linux/log2.h:57:13: warning: The result of the left shift is undefined due to shifting by '32', which is greater or equal to the width of type 'unsigned long' [clang-analyzer-core.UndefinedBinaryOperatorResult] return 1UL << fls_long(n - 1); vim +21 include/asm-generic/bitops/fls64.h a54baa1487c51c Akinobu Mita 2006-03-26 6 d57594c203b1e7 Alexander van Heukelum 2008-03-15 7 /** d57594c203b1e7 Alexander van Heukelum 2008-03-15 8 * fls64 - find last set bit in a 64-bit word d57594c203b1e7 Alexander van Heukelum 2008-03-15 9 * @x: the word to search d57594c203b1e7 Alexander van Heukelum 2008-03-15 10 * d57594c203b1e7 Alexander van Heukelum 2008-03-15 11 * This is defined in a similar way as the libc and compiler builtin d57594c203b1e7 Alexander van Heukelum 2008-03-15 12 * ffsll, but returns the position of the most significant set bit. d57594c203b1e7 Alexander van Heukelum 2008-03-15 13 * d57594c203b1e7 Alexander van Heukelum 2008-03-15 14 * fls64(value) returns 0 if value is 0 or the position of the last d57594c203b1e7 Alexander van Heukelum 2008-03-15 15 * set bit if value is nonzero. The last (most significant) bit is d57594c203b1e7 Alexander van Heukelum 2008-03-15 16 * at position 64. d57594c203b1e7 Alexander van Heukelum 2008-03-15 17 */ d57594c203b1e7 Alexander van Heukelum 2008-03-15 18 #if BITS_PER_LONG == 32 c8399943bdb70f Andi Kleen 2009-01-12 19 static __always_inline int fls64(__u64 x) 2dfc383ad587bb Akinobu Mita 2006-03-26 20 { 2dfc383ad587bb Akinobu Mita 2006-03-26 @21 __u32 h = x >> 32; 2dfc383ad587bb Akinobu Mita 2006-03-26 22 if (h) 2dfc383ad587bb Akinobu Mita 2006-03-26 23 return fls(h) + 32; 2dfc383ad587bb Akinobu Mita 2006-03-26 24 return fls(x); 2dfc383ad587bb Akinobu Mita 2006-03-26 25 } d57594c203b1e7 Alexander van Heukelum 2008-03-15 26 #elif BITS_PER_LONG == 64 c8399943bdb70f Andi Kleen 2009-01-12 27 static __always_inline int fls64(__u64 x) d57594c203b1e7 Alexander van Heukelum 2008-03-15 28 { d57594c203b1e7 Alexander van Heukelum 2008-03-15 29 if (x == 0) d57594c203b1e7 Alexander van Heukelum 2008-03-15 30 return 0; d57594c203b1e7 Alexander van Heukelum 2008-03-15 31 return __fls(x) + 1; d57594c203b1e7 Alexander van Heukelum 2008-03-15 32 } d57594c203b1e7 Alexander van Heukelum 2008-03-15 33 #else d57594c203b1e7 Alexander van Heukelum 2008-03-15 34 #error BITS_PER_LONG not 32 or 64 d57594c203b1e7 Alexander van Heukelum 2008-03-15 35 #endif 2dfc383ad587bb Akinobu Mita 2006-03-26 36 :::::: The code at line 21 was first introduced by commit :::::: 2dfc383ad587bbead84739a9ff9273df3eda983d [PATCH] bitops: generic fls64() :::::: TO: Akinobu Mita <[email protected]> :::::: CC: Linus Torvalds <[email protected]> --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/[email protected] _______________________________________________ kbuild mailing list -- [email protected] To unsubscribe send an email to [email protected]
