tree: https://github.com/hnaz/linux-mm master head: 5d9ee416b5701096536c7a63c04dbe25012baa9e commit: 79181dfcc4b8c2091126a8b3175957a598ae61e1 [90/340] x86/mm: use helper fault_signal_pending() reproduce: # apt-get install sparse # sparse version: v0.6.1-174-g094d5a94-dirty git checkout 79181dfcc4b8c2091126a8b3175957a598ae61e1 make ARCH=x86_64 allmodconfig make C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' If you fix the issue, kindly add following tag Reported-by: kbuild test robot <lkp@xxxxxxxxx> sparse warnings: (new ones prefixed by >>) >> arch/x86/mm/fault.c:1468:34: sparse: sparse: incorrect type in argument 1 (different base types) @@ expected unsigned int fault_flags @@ got restricted vm_fault_t [assignedunsigned int fault_flags @@ >> arch/x86/mm/fault.c:1468:34: sparse: expected unsigned int fault_flags >> arch/x86/mm/fault.c:1468:34: sparse: got restricted vm_fault_t [assigned] [usertype] fault >> include/linux/sched/signal.h:381:16: sparse: sparse: restricted vm_fault_t degrades to integer vim +1468 arch/x86/mm/fault.c 1392 1393 /* 1394 * Kernel-mode access to the user address space should only occur 1395 * on well-defined single instructions listed in the exception 1396 * tables. But, an erroneous kernel fault occurring outside one of 1397 * those areas which also holds mmap_sem might deadlock attempting 1398 * to validate the fault against the address space. 1399 * 1400 * Only do the expensive exception table search when we might be at 1401 * risk of a deadlock. This happens if we 1402 * 1. Failed to acquire mmap_sem, and 1403 * 2. The access did not originate in userspace. 1404 */ 1405 if (unlikely(!down_read_trylock(&mm->mmap_sem))) { 1406 if (!user_mode(regs) && !search_exception_tables(regs->ip)) { 1407 /* 1408 * Fault from code in kernel from 1409 * which we do not expect faults. 1410 */ 1411 bad_area_nosemaphore(regs, hw_error_code, address); 1412 return; 1413 } 1414 retry: 1415 down_read(&mm->mmap_sem); 1416 } else { 1417 /* 1418 * The above down_read_trylock() might have succeeded in 1419 * which case we'll have missed the might_sleep() from 1420 * down_read(): 1421 */ 1422 might_sleep(); 1423 } 1424 1425 vma = find_vma(mm, address); 1426 if (unlikely(!vma)) { 1427 bad_area(regs, hw_error_code, address); 1428 return; 1429 } 1430 if (likely(vma->vm_start <= address)) 1431 goto good_area; 1432 if (unlikely(!(vma->vm_flags & VM_GROWSDOWN))) { 1433 bad_area(regs, hw_error_code, address); 1434 return; 1435 } 1436 if (unlikely(expand_stack(vma, address))) { 1437 bad_area(regs, hw_error_code, address); 1438 return; 1439 } 1440 1441 /* 1442 * Ok, we have a good vm_area for this memory access, so 1443 * we can handle it.. 1444 */ 1445 good_area: 1446 if (unlikely(access_error(hw_error_code, vma))) { 1447 bad_area_access_error(regs, hw_error_code, address, vma); 1448 return; 1449 } 1450 1451 /* 1452 * If for any reason at all we couldn't handle the fault, 1453 * make sure we exit gracefully rather than endlessly redo 1454 * the fault. Since we never set FAULT_FLAG_RETRY_NOWAIT, if 1455 * we get VM_FAULT_RETRY back, the mmap_sem has been unlocked. 1456 * 1457 * Note that handle_userfault() may also release and reacquire mmap_sem 1458 * (and not return with VM_FAULT_RETRY), when returning to userland to 1459 * repeat the page fault later with a VM_FAULT_NOPAGE retval 1460 * (potentially after handling any pending signal during the return to 1461 * userland). The return to userland is identified whenever 1462 * FAULT_FLAG_USER|FAULT_FLAG_KILLABLE are both set in flags. 1463 */ 1464 fault = handle_mm_fault(vma, address, flags); 1465 major |= fault & VM_FAULT_MAJOR; 1466 1467 /* Quick path to respond to signals */ > 1468 if (fault_signal_pending(fault, regs)) { 1469 if (!user_mode(regs)) 1470 no_context(regs, hw_error_code, address, SIGBUS, 1471 BUS_ADRERR); 1472 return; 1473 } 1474 1475 /* 1476 * If we need to retry the mmap_sem has already been released, 1477 * and if there is a fatal signal pending there is no guarantee 1478 * that we made any progress. Handle this case first. 1479 */ 1480 if (unlikely((fault & VM_FAULT_RETRY) && 1481 (flags & FAULT_FLAG_ALLOW_RETRY))) { 1482 /* Retry at most once */ 1483 flags &= ~FAULT_FLAG_ALLOW_RETRY; 1484 flags |= FAULT_FLAG_TRIED; 1485 goto retry; 1486 } 1487 1488 up_read(&mm->mmap_sem); 1489 if (unlikely(fault & VM_FAULT_ERROR)) { 1490 mm_fault_error(regs, hw_error_code, address, fault); 1491 return; 1492 } 1493 1494 /* 1495 * Major/minor page fault accounting. If any of the events 1496 * returned VM_FAULT_MAJOR, we account it as a major fault. 1497 */ 1498 if (major) { 1499 tsk->maj_flt++; 1500 perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, regs, address); 1501 } else { 1502 tsk->min_flt++; 1503 perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, regs, address); 1504 } 1505 1506 check_v8086_mode(regs, address, tsk); 1507 } 1508 NOKPROBE_SYMBOL(do_user_addr_fault); 1509 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
