tree: https://android.googlesource.com/kernel/common android12-5.10 head: 9e4d84273c9d786ee7592970f0a46c1c28eb3c18 commit: 9e4d84273c9d786ee7592970f0a46c1c28eb3c18 [3/3] ANDROID: Fix sparse warning in __handle_speculative_fault caused by SPF config: arm64-randconfig-s031-20210209 (attached as .config) compiler: aarch64-linux-gcc (GCC) 9.3.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # apt-get install sparse # sparse version: v0.6.3-215-g0fb77bb6-dirty git remote add android-common https://android.googlesource.com/kernel/common git fetch --no-tags android-common android12-5.10 git checkout 9e4d84273c9d786ee7592970f0a46c1c28eb3c18 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=arm64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; "sparse warnings: (new ones prefixed by >>)" arch/arm64/mm/fault.c:494:31: sparse: sparse: incorrect type in return expression (different base types) @@ expected int @@ got restricted vm_fault_t @@ arch/arm64/mm/fault.c:494:31: sparse: expected int arch/arm64/mm/fault.c:494:31: sparse: got restricted vm_fault_t arch/arm64/mm/fault.c:594:15: sparse: expected restricted vm_fault_t [assigned] [usertype] fault arch/arm64/mm/fault.c:594:15: sparse: got int arch/arm64/mm/fault.c:623:13: sparse: sparse: restricted vm_fault_t degrades to integer arch/arm64/mm/fault.c:623:13: sparse: sparse: restricted vm_fault_t degrades to integer arch/arm64/mm/fault.c:666:39: sparse: sparse: restricted vm_fault_t degrades to integer vim +594 arch/arm64/mm/fault.c c49bd02f4c7412 Anshuman Khandual 2019-06-07 510 1ad9551f1d90e3 Peter Collingbourne 2021-01-22 511 static int __kprobes do_page_fault(unsigned long far, unsigned int esr, 1d18c47c735e8a Catalin Marinas 2012-03-05 512 struct pt_regs *regs) 1d18c47c735e8a Catalin Marinas 2012-03-05 513 { 2d2837fab5fada Eric W. Biederman 2018-09-22 514 const struct fault_info *inf; 61681036004318 Anshuman Khandual 2019-06-03 515 struct mm_struct *mm = current->mm; 6a1bb025d28e10 Peter Xu 2020-08-11 516 vm_fault_t fault; 6cb4d9a2870d20 Anshuman Khandual 2020-04-10 517 unsigned long vm_flags = VM_ACCESS_FLAGS; dde1607248328c Peter Xu 2020-04-01 518 unsigned int mm_flags = FAULT_FLAG_DEFAULT; 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 519 struct vm_area_struct *vma = NULL; 1ad9551f1d90e3 Peter Collingbourne 2021-01-22 520 unsigned long addr = untagged_addr(far); db6f41063cbdb5 Will Deacon 2013-07-19 521 b98cca444d287a Anshuman Khandual 2019-07-16 522 if (kprobe_page_fault(regs, esr)) 2dd0e8d2d2a157 Sandeepa Prabhu 2016-07-08 523 return 0; 2dd0e8d2d2a157 Sandeepa Prabhu 2016-07-08 524 1d18c47c735e8a Catalin Marinas 2012-03-05 525 /* 1d18c47c735e8a Catalin Marinas 2012-03-05 526 * If we're in an interrupt or have no user context, we must not take 1d18c47c735e8a Catalin Marinas 2012-03-05 527 * the fault. 1d18c47c735e8a Catalin Marinas 2012-03-05 528 */ 70ffdb9393a726 David Hildenbrand 2015-05-11 529 if (faulthandler_disabled() || !mm) 1d18c47c735e8a Catalin Marinas 2012-03-05 530 goto no_context; 1d18c47c735e8a Catalin Marinas 2012-03-05 531 759496ba6407c6 Johannes Weiner 2013-09-12 532 if (user_mode(regs)) 759496ba6407c6 Johannes Weiner 2013-09-12 533 mm_flags |= FAULT_FLAG_USER; 759496ba6407c6 Johannes Weiner 2013-09-12 534 541ec870ef3143 Mark Rutland 2016-05-31 535 if (is_el0_instruction_abort(esr)) { 759496ba6407c6 Johannes Weiner 2013-09-12 536 vm_flags = VM_EXEC; 01de1776f62e64 Anshuman Khandual 2019-05-05 537 mm_flags |= FAULT_FLAG_INSTRUCTION; c49bd02f4c7412 Anshuman Khandual 2019-06-07 538 } else if (is_write_abort(esr)) { 759496ba6407c6 Johannes Weiner 2013-09-12 539 vm_flags = VM_WRITE; 759496ba6407c6 Johannes Weiner 2013-09-12 540 mm_flags |= FAULT_FLAG_WRITE; 759496ba6407c6 Johannes Weiner 2013-09-12 541 } 759496ba6407c6 Johannes Weiner 2013-09-12 542 356607f21e6035 Andrey Konovalov 2018-12-28 543 if (is_ttbr0_addr(addr) && is_el1_permission_fault(addr, esr, regs)) { e19a6ee2460bdd James Morse 2016-06-20 544 /* regs->orig_addr_limit may be 0 if we entered from EL0 */ e19a6ee2460bdd James Morse 2016-06-20 545 if (regs->orig_addr_limit == KERNEL_DS) c870f14ea115bb Mark Rutland 2018-05-21 546 die_kernel_fault("access to user memory with fs=KERNEL_DS", c870f14ea115bb Mark Rutland 2018-05-21 547 addr, esr, regs); 705441960033e6 James Morse 2016-02-05 548 9adeb8e72dbfe9 Laura Abbott 2016-08-09 549 if (is_el1_instruction_abort(esr)) c870f14ea115bb Mark Rutland 2018-05-21 550 die_kernel_fault("execution of user memory", c870f14ea115bb Mark Rutland 2018-05-21 551 addr, esr, regs); 9adeb8e72dbfe9 Laura Abbott 2016-08-09 552 57f4959bad0a15 James Morse 2016-02-05 553 if (!search_exception_tables(regs->pc)) c870f14ea115bb Mark Rutland 2018-05-21 554 die_kernel_fault("access to user memory outside uaccess routines", c870f14ea115bb Mark Rutland 2018-05-21 555 addr, esr, regs); 57f4959bad0a15 James Morse 2016-02-05 556 } 338d4f49d6f711 James Morse 2015-07-22 557 0e3a9026396cd7 Punit Agrawal 2017-06-08 558 perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr); 0e3a9026396cd7 Punit Agrawal 2017-06-08 559 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 560 /* 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 561 * let's try a speculative page fault without grabbing the 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 562 * mmap_sem. 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 563 */ 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 564 fault = handle_speculative_fault(mm, addr, mm_flags, &vma); 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 565 if (fault != VM_FAULT_RETRY) 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 566 goto done; 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 567 1d18c47c735e8a Catalin Marinas 2012-03-05 568 /* 1d18c47c735e8a Catalin Marinas 2012-03-05 569 * As per x86, we may deadlock here. However, since the kernel only 1d18c47c735e8a Catalin Marinas 2012-03-05 570 * validly references user space from well defined areas of the code, 1d18c47c735e8a Catalin Marinas 2012-03-05 571 * we can bug out early if this is from code which shouldn't. 1d18c47c735e8a Catalin Marinas 2012-03-05 572 */ d8ed45c5dcd455 Michel Lespinasse 2020-06-08 573 if (!mmap_read_trylock(mm)) { 1d18c47c735e8a Catalin Marinas 2012-03-05 574 if (!user_mode(regs) && !search_exception_tables(regs->pc)) 1d18c47c735e8a Catalin Marinas 2012-03-05 575 goto no_context; 1d18c47c735e8a Catalin Marinas 2012-03-05 576 retry: d8ed45c5dcd455 Michel Lespinasse 2020-06-08 577 mmap_read_lock(mm); 1d18c47c735e8a Catalin Marinas 2012-03-05 578 } else { 1d18c47c735e8a Catalin Marinas 2012-03-05 579 /* 1d18c47c735e8a Catalin Marinas 2012-03-05 580 * The above down_read_trylock() might have succeeded in which 1d18c47c735e8a Catalin Marinas 2012-03-05 581 * case, we'll have missed the might_sleep() from down_read(). 1d18c47c735e8a Catalin Marinas 2012-03-05 582 */ 1d18c47c735e8a Catalin Marinas 2012-03-05 583 might_sleep(); 1d18c47c735e8a Catalin Marinas 2012-03-05 584 #ifdef CONFIG_DEBUG_VM a0509313d5dea0 Anshuman Khandual 2019-06-03 585 if (!user_mode(regs) && !search_exception_tables(regs->pc)) { d8ed45c5dcd455 Michel Lespinasse 2020-06-08 586 mmap_read_unlock(mm); 1d18c47c735e8a Catalin Marinas 2012-03-05 587 goto no_context; a0509313d5dea0 Anshuman Khandual 2019-06-03 588 } 1d18c47c735e8a Catalin Marinas 2012-03-05 589 #endif 1d18c47c735e8a Catalin Marinas 2012-03-05 590 } 1d18c47c735e8a Catalin Marinas 2012-03-05 591 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 592 if (!vma || !can_reuse_spf_vma(vma, addr)) 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 593 vma = find_vma(mm, addr); 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 @594 fault = __do_page_fault(vma, addr, mm_flags, vm_flags, regs); 1d18c47c735e8a Catalin Marinas 2012-03-05 595 b502f038f2ffc9 Peter Xu 2020-04-01 596 /* Quick path to respond to signals */ b502f038f2ffc9 Peter Xu 2020-04-01 597 if (fault_signal_pending(fault, regs)) { 289d07a2dc6c6b Mark Rutland 2017-07-11 598 if (!user_mode(regs)) 289d07a2dc6c6b Mark Rutland 2017-07-11 599 goto no_context; 1d18c47c735e8a Catalin Marinas 2012-03-05 600 return 0; 289d07a2dc6c6b Mark Rutland 2017-07-11 601 } 1d18c47c735e8a Catalin Marinas 2012-03-05 602 b502f038f2ffc9 Peter Xu 2020-04-01 603 if (fault & VM_FAULT_RETRY) { 0e3a9026396cd7 Punit Agrawal 2017-06-08 604 if (mm_flags & FAULT_FLAG_ALLOW_RETRY) { 569ba74a7ba69f Mark Salyzyn 2015-09-21 605 mm_flags |= FAULT_FLAG_TRIED; 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 606 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 607 /* 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 608 * Do not try to reuse this vma and fetch it 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 609 * again since we will release the mmap_sem. 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 610 */ 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 611 vma = NULL; 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 612 1d18c47c735e8a Catalin Marinas 2012-03-05 613 goto retry; 1d18c47c735e8a Catalin Marinas 2012-03-05 614 } 1d18c47c735e8a Catalin Marinas 2012-03-05 615 } d8ed45c5dcd455 Michel Lespinasse 2020-06-08 616 mmap_read_unlock(mm); 1d18c47c735e8a Catalin Marinas 2012-03-05 617 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 618 done: 2fd69fa6bcab98 Mahendran Ganesh 2018-05-04 619 1d18c47c735e8a Catalin Marinas 2012-03-05 620 /* 0e3a9026396cd7 Punit Agrawal 2017-06-08 621 * Handle the "normal" (no error) case first. 1d18c47c735e8a Catalin Marinas 2012-03-05 622 */ 1d18c47c735e8a Catalin Marinas 2012-03-05 623 if (likely(!(fault & (VM_FAULT_ERROR | VM_FAULT_BADMAP | 6a1bb025d28e10 Peter Xu 2020-08-11 624 VM_FAULT_BADACCESS)))) 1d18c47c735e8a Catalin Marinas 2012-03-05 625 return 0; 1d18c47c735e8a Catalin Marinas 2012-03-05 626 871341023c771a Johannes Weiner 2013-09-12 627 /* 871341023c771a Johannes Weiner 2013-09-12 628 * If we are in kernel mode at this point, we have no context to 871341023c771a Johannes Weiner 2013-09-12 629 * handle this fault with. 871341023c771a Johannes Weiner 2013-09-12 630 */ 871341023c771a Johannes Weiner 2013-09-12 631 if (!user_mode(regs)) 871341023c771a Johannes Weiner 2013-09-12 632 goto no_context; 871341023c771a Johannes Weiner 2013-09-12 633 1d18c47c735e8a Catalin Marinas 2012-03-05 634 if (fault & VM_FAULT_OOM) { 1d18c47c735e8a Catalin Marinas 2012-03-05 635 /* 1d18c47c735e8a Catalin Marinas 2012-03-05 636 * We ran out of memory, call the OOM killer, and return to 1d18c47c735e8a Catalin Marinas 2012-03-05 637 * userspace (which will retry the fault, or kill us if we got 1d18c47c735e8a Catalin Marinas 2012-03-05 638 * oom-killed). 1d18c47c735e8a Catalin Marinas 2012-03-05 639 */ 1d18c47c735e8a Catalin Marinas 2012-03-05 640 pagefault_out_of_memory(); 1d18c47c735e8a Catalin Marinas 2012-03-05 641 return 0; 1d18c47c735e8a Catalin Marinas 2012-03-05 642 } 1d18c47c735e8a Catalin Marinas 2012-03-05 643 2d2837fab5fada Eric W. Biederman 2018-09-22 644 inf = esr_to_fault_info(esr); 559d8d91a89cc2 Eric W. Biederman 2018-09-22 645 set_thread_esr(addr, esr); 1d18c47c735e8a Catalin Marinas 2012-03-05 646 if (fault & VM_FAULT_SIGBUS) { 1d18c47c735e8a Catalin Marinas 2012-03-05 647 /* 1d18c47c735e8a Catalin Marinas 2012-03-05 648 * We had some memory, but were unable to successfully fix up 1d18c47c735e8a Catalin Marinas 2012-03-05 649 * this page fault. 1d18c47c735e8a Catalin Marinas 2012-03-05 650 */ 1ad9551f1d90e3 Peter Collingbourne 2021-01-22 651 arm64_force_sig_fault(SIGBUS, BUS_ADRERR, far, inf->name); 9ea3a9743cac4f Eric W. Biederman 2018-09-22 652 } else if (fault & (VM_FAULT_HWPOISON_LARGE | VM_FAULT_HWPOISON)) { 9ea3a9743cac4f Eric W. Biederman 2018-09-22 653 unsigned int lsb; 9ea3a9743cac4f Eric W. Biederman 2018-09-22 654 9ea3a9743cac4f Eric W. Biederman 2018-09-22 655 lsb = PAGE_SHIFT; 9ea3a9743cac4f Eric W. Biederman 2018-09-22 656 if (fault & VM_FAULT_HWPOISON_LARGE) 9ea3a9743cac4f Eric W. Biederman 2018-09-22 657 lsb = hstate_index_to_shift(VM_FAULT_GET_HINDEX(fault)); 92ff0674f5d801 Will Deacon 2018-02-20 658 1ad9551f1d90e3 Peter Collingbourne 2021-01-22 659 arm64_force_sig_mceerr(BUS_MCEERR_AR, far, lsb, inf->name); 1d18c47c735e8a Catalin Marinas 2012-03-05 660 } else { 1d18c47c735e8a Catalin Marinas 2012-03-05 661 /* 1d18c47c735e8a Catalin Marinas 2012-03-05 662 * Something tried to access memory that isn't in our memory 1d18c47c735e8a Catalin Marinas 2012-03-05 663 * map. 1d18c47c735e8a Catalin Marinas 2012-03-05 664 */ feca355b3d8eba Eric W. Biederman 2018-09-22 665 arm64_force_sig_fault(SIGSEGV, feca355b3d8eba Eric W. Biederman 2018-09-22 666 fault == VM_FAULT_BADACCESS ? SEGV_ACCERR : SEGV_MAPERR, 1ad9551f1d90e3 Peter Collingbourne 2021-01-22 667 far, inf->name); 1d18c47c735e8a Catalin Marinas 2012-03-05 668 } 1d18c47c735e8a Catalin Marinas 2012-03-05 669 1d18c47c735e8a Catalin Marinas 2012-03-05 670 return 0; 1d18c47c735e8a Catalin Marinas 2012-03-05 671 1d18c47c735e8a Catalin Marinas 2012-03-05 672 no_context: 67ce16ec15ce9d Kristina Martsenko 2017-06-09 673 __do_kernel_fault(addr, esr, regs); 1d18c47c735e8a Catalin Marinas 2012-03-05 674 return 0; 1d18c47c735e8a Catalin Marinas 2012-03-05 675 } 1d18c47c735e8a Catalin Marinas 2012-03-05 676 :::::: The code at line 594 was first introduced by commit :::::: 2fd69fa6bcab984b56ccfd4860b10f11f1966bed FROMLIST: arm64/mm: add speculative page fault :::::: TO: Mahendran Ganesh <opensource.ganesh(a)gmail.com&gt; :::::: CC: Suren Baghdasaryan <surenb(a)google.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org