From: kernel test robot <lkp@intel.com>
To: Isaku Yamahata <isaku.yamahata@intel.com>
Cc: oe-kbuild-all@lists.linux.dev, Kai Huang <kai.huang@intel.com>
Subject: [intel-tdx:kvm-upstream-next 150/348] arch/x86/kvm/mmu/tdp_mmu.c:627:17: sparse: sparse: incorrect type in argument 1 (different address spaces)
Date: Thu, 26 Oct 2023 01:02:19 +0800 [thread overview]
Message-ID: <202310260000.R8Frcl4L-lkp@intel.com> (raw)
tree: https://github.com/intel/tdx.git kvm-upstream-next
head: ce98d11dcbe13d1a02ce9f4f49d422d6db223b60
commit: 66f49b85cc57cf2bb3a3c9d4ad579b359cb58073 [150/348] KVM: x86/tdp_mmu: Support TDX private mapping for TDP MMU
config: x86_64-randconfig-123-20231025 (https://download.01.org/0day-ci/archive/20231026/202310260000.R8Frcl4L-lkp@intel.com/config)
compiler: gcc-11 (Debian 11.3.0-12) 11.3.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231026/202310260000.R8Frcl4L-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/202310260000.R8Frcl4L-lkp@intel.com/
sparse warnings: (new ones prefixed by >>)
>> arch/x86/kvm/mmu/tdp_mmu.c:627:17: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [usertype] *sptep @@ got unsigned long long [noderef] [usertype] __rcu * @@
arch/x86/kvm/mmu/tdp_mmu.c:627:17: sparse: expected unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c:627:17: sparse: got unsigned long long [noderef] [usertype] __rcu *
>> arch/x86/kvm/mmu/tdp_mmu.c:691:14: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected void const volatile *v @@ got unsigned long long [noderef] [usertype] __rcu *__ai_ptr @@
arch/x86/kvm/mmu/tdp_mmu.c:691:14: sparse: expected void const volatile *v
arch/x86/kvm/mmu/tdp_mmu.c:691:14: sparse: got unsigned long long [noderef] [usertype] __rcu *__ai_ptr
>> arch/x86/kvm/mmu/tdp_mmu.c:691:14: sparse: sparse: cast removes address space '__rcu' of expression
>> arch/x86/kvm/mmu/tdp_mmu.c:691:14: sparse: sparse: cast removes address space '__rcu' of expression
>> arch/x86/kvm/mmu/tdp_mmu.c:691:14: sparse: sparse: cast removes address space '__rcu' of expression
>> arch/x86/kvm/mmu/tdp_mmu.c:691:14: sparse: sparse: cast removes address space '__rcu' of expression
>> arch/x86/kvm/mmu/tdp_mmu.c:838:30: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [usertype] *sptep @@ got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:838:30: sparse: expected unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c:838:30: sparse: got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep
arch/x86/kvm/mmu/tdp_mmu.c:846:28: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [usertype] *sptep @@ got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:846:28: sparse: expected unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c:846:28: sparse: got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep
>> arch/x86/kvm/mmu/tdp_mmu.c:1344:25: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [usertype] *sptep @@ got unsigned long long [noderef] [usertype] __rcu *[addressable] [usertype] sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:1344:25: sparse: expected unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c:1344:25: sparse: got unsigned long long [noderef] [usertype] __rcu *[addressable] [usertype] sptep
arch/x86/kvm/mmu/tdp_mmu.c:1620:9: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [usertype] *sptep @@ got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:1620:9: sparse: expected unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c:1620:9: sparse: got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep
arch/x86/kvm/mmu/tdp_mmu.c:336:13: sparse: sparse: context imbalance in 'tdp_mmu_unlink_sp' - different lock contexts for basic block
>> arch/x86/kvm/mmu/tdp_mmu.c:691:14: sparse: sparse: dereference of noderef expression
>> arch/x86/kvm/mmu/tdp_mmu.c:691:14: sparse: sparse: dereference of noderef expression
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [usertype] *sptep @@ got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: expected unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep
>> arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [noderef] [usertype] __rcu *[addressable] [usertype] sptep @@ got unsigned long long [usertype] *sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: expected unsigned long long [noderef] [usertype] __rcu *[addressable] [usertype] sptep
arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: got unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c: note: in included file (through include/linux/rculist.h, include/linux/pid.h, include/linux/sched.h, ...):
include/linux/rcupdate.h:780:9: sparse: sparse: context imbalance in '__tdp_mmu_zap_root' - unexpected unlock
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [usertype] *sptep @@ got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: expected unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep
>> arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [noderef] [usertype] __rcu *[addressable] [usertype] sptep @@ got unsigned long long [usertype] *sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: expected unsigned long long [noderef] [usertype] __rcu *[addressable] [usertype] sptep
arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: got unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [usertype] *sptep @@ got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: expected unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep
>> arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [noderef] [usertype] __rcu *[addressable] [usertype] sptep @@ got unsigned long long [usertype] *sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: expected unsigned long long [noderef] [usertype] __rcu *[addressable] [usertype] sptep
arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: got unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [usertype] *sptep @@ got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: expected unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep
>> arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [noderef] [usertype] __rcu *[addressable] [usertype] sptep @@ got unsigned long long [usertype] *sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: expected unsigned long long [noderef] [usertype] __rcu *[addressable] [usertype] sptep
arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: got unsigned long long [usertype] *sptep
include/linux/rcupdate.h:780:9: sparse: sparse: context imbalance in 'tdp_mmu_alloc_sp_for_split' - unexpected unlock
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [usertype] *sptep @@ got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: expected unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep
>> arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [noderef] [usertype] __rcu *[addressable] [usertype] sptep @@ got unsigned long long [usertype] *sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: expected unsigned long long [noderef] [usertype] __rcu *[addressable] [usertype] sptep
arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: got unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [usertype] *sptep @@ got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: expected unsigned long long [usertype] *sptep
arch/x86/kvm/mmu/tdp_mmu.c:736:34: sparse: got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep
>> arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected unsigned long long [noderef] [usertype] __rcu *[addressable] [usertype] sptep @@ got unsigned long long [usertype] *sptep @@
arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: expected unsigned long long [noderef] [usertype] __rcu *[addressable] [usertype] sptep
arch/x86/kvm/mmu/tdp_mmu.c:774:42: sparse: got unsigned long long [usertype] *sptep
vim +627 arch/x86/kvm/mmu/tdp_mmu.c
521
522 /**
523 * handle_changed_spte - handle bookkeeping associated with an SPTE change
524 * @kvm: kvm instance
525 * @as_id: the address space of the paging structure the SPTE was a part of
526 * @gfn: the base GFN that was mapped by the SPTE
527 * @old_spte: The value of the SPTE before the change
528 * @new_spte: The value of the SPTE after the change
529 * @role: the role of the PT the SPTE is part of in the paging structure
530 * @shared: This operation may not be running under the exclusive use of
531 * the MMU lock and the operation must synchronize with other
532 * threads that might be modifying SPTEs.
533 *
534 * Handle bookkeeping that might result from the modification of a SPTE. Note,
535 * dirty logging updates are handled in common code, not here (see make_spte()
536 * and fast_pf_fix_direct_spte()).
537 */
538 static void handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
539 u64 old_spte, u64 new_spte,
540 union kvm_mmu_page_role role, bool shared)
541 {
542 bool is_private = kvm_mmu_page_role_is_private(role);
543 int level = role.level;
544 bool was_present = is_shadow_present_pte(old_spte);
545 bool is_present = is_shadow_present_pte(new_spte);
546 bool was_leaf = was_present && is_last_spte(old_spte, level);
547 bool is_leaf = is_present && is_last_spte(new_spte, level);
548 kvm_pfn_t old_pfn = spte_to_pfn(old_spte);
549 kvm_pfn_t new_pfn = spte_to_pfn(new_spte);
550 bool pfn_changed = old_pfn != new_pfn;
551
552 WARN_ON_ONCE(level > PT64_ROOT_MAX_LEVEL);
553 WARN_ON_ONCE(level < PG_LEVEL_4K);
554 WARN_ON_ONCE(gfn & (KVM_PAGES_PER_HPAGE(level) - 1));
555
556 /*
557 * If this warning were to trigger it would indicate that there was a
558 * missing MMU notifier or a race with some notifier handler.
559 * A present, leaf SPTE should never be directly replaced with another
560 * present leaf SPTE pointing to a different PFN. A notifier handler
561 * should be zapping the SPTE before the main MM's page table is
562 * changed, or the SPTE should be zeroed, and the TLBs flushed by the
563 * thread before replacement.
564 */
565 if (was_leaf && is_leaf && pfn_changed) {
566 pr_err("Invalid SPTE change: cannot replace a present leaf\n"
567 "SPTE with another present leaf SPTE mapping a\n"
568 "different PFN!\n"
569 "as_id: %d gfn: %llx old_spte: %llx new_spte: %llx level: %d",
570 as_id, gfn, old_spte, new_spte, level);
571
572 /*
573 * Crash the host to prevent error propagation and guest data
574 * corruption.
575 */
576 BUG();
577 }
578
579 if (old_spte == new_spte)
580 return;
581
582 trace_kvm_tdp_mmu_spte_changed(as_id, gfn, level, old_spte, new_spte);
583
584 if (is_leaf)
585 check_spte_writable_invariants(new_spte);
586
587 /*
588 * The only times a SPTE should be changed from a non-present to
589 * non-present state is when an MMIO entry is installed/modified/
590 * removed. In that case, there is nothing to do here.
591 */
592 if (!was_present && !is_present) {
593 /*
594 * If this change does not involve a MMIO SPTE or removed SPTE,
595 * it is unexpected. Log the change, though it should not
596 * impact the guest since both the former and current SPTEs
597 * are nonpresent.
598 */
599 if (WARN_ON_ONCE(!is_mmio_spte(kvm, old_spte) &&
600 !is_mmio_spte(kvm, new_spte) &&
601 !is_removed_spte(new_spte)))
602 pr_err("Unexpected SPTE change! Nonpresent SPTEs\n"
603 "should not be replaced with another,\n"
604 "different nonpresent SPTE, unless one or both\n"
605 "are MMIO SPTEs, or the new SPTE is\n"
606 "a temporary removed SPTE.\n"
607 "as_id: %d gfn: %llx old_spte: %llx new_spte: %llx level: %d",
608 as_id, gfn, old_spte, new_spte, level);
609 return;
610 }
611
612 if (is_leaf != was_leaf)
613 kvm_update_page_stats(kvm, level, is_leaf ? 1 : -1);
614
615 if (was_leaf && is_dirty_spte(old_spte) &&
616 (!is_present || !is_dirty_spte(new_spte) || pfn_changed))
617 kvm_set_pfn_dirty(old_pfn);
618
619 /*
620 * Recursively handle child PTs if the change removed a subtree from
621 * the paging structure. Note the WARN on the PFN changing without the
622 * SPTE being converted to a hugepage (leaf) or being zapped. Shadow
623 * pages are kernel allocations and should never be migrated.
624 */
625 if (was_present && !was_leaf &&
626 (is_leaf || !is_present || WARN_ON_ONCE(pfn_changed))) {
> 627 KVM_BUG_ON(is_private != is_private_sptep(spte_to_child_pt(old_spte, level)),
628 kvm);
629 handle_removed_pt(kvm, spte_to_child_pt(old_spte, level), shared);
630 }
631
632 /*
633 * Secure-EPT requires to remove Secure-EPT tables after removing
634 * children. hooks after handling lower page table by above
635 * handle_remove_pt().
636 */
637 if (is_private && !is_present)
638 handle_removed_private_spte(kvm, gfn, old_spte, new_spte, role.level);
639
640 if (was_leaf && is_accessed_spte(old_spte) &&
641 (!is_present || !is_accessed_spte(new_spte) || pfn_changed))
642 kvm_set_pfn_accessed(spte_to_pfn(old_spte));
643 }
644
645 static int __must_check __set_private_spte_present(struct kvm *kvm, tdp_ptep_t sptep,
646 gfn_t gfn, u64 old_spte,
647 u64 new_spte, int level)
648 {
649 bool was_present = is_shadow_present_pte(old_spte);
650 bool is_present = is_shadow_present_pte(new_spte);
651 bool is_leaf = is_present && is_last_spte(new_spte, level);
652 kvm_pfn_t new_pfn = spte_to_pfn(new_spte);
653 int ret = 0;
654
655 lockdep_assert_held(&kvm->mmu_lock);
656 /* TDP MMU doesn't change present -> present */
657 KVM_BUG_ON(was_present, kvm);
658
659 /*
660 * Use different call to either set up middle level
661 * private page table, or leaf.
662 */
663 if (is_leaf)
664 ret = static_call(kvm_x86_set_private_spte)(kvm, gfn, level, new_pfn);
665 else {
666 void *private_spt = get_private_spt(gfn, new_spte, level);
667
668 KVM_BUG_ON(!private_spt, kvm);
669 ret = static_call(kvm_x86_link_private_spt)(kvm, gfn, level, private_spt);
670 }
671
672 return ret;
673 }
674
675 static int __must_check set_private_spte_present(struct kvm *kvm, tdp_ptep_t sptep,
676 gfn_t gfn, u64 old_spte,
677 u64 new_spte, int level)
678 {
679 int ret;
680
681 /*
682 * For private page table, callbacks are needed to propagate SPTE
683 * change into the protected page table. In order to atomically update
684 * both the SPTE and the protected page tables with callbacks, utilize
685 * freezing SPTE.
686 * - Freeze the SPTE. Set entry to REMOVED_SPTE.
687 * - Trigger callbacks for protected page tables.
688 * - Unfreeze the SPTE. Set the entry to new_spte.
689 */
690 lockdep_assert_held(&kvm->mmu_lock);
> 691 if (!try_cmpxchg64(sptep, &old_spte, REMOVED_SPTE))
692 return -EBUSY;
693
694 ret = __set_private_spte_present(kvm, sptep, gfn, old_spte, new_spte, level);
695 if (ret)
696 __kvm_tdp_mmu_write_spte(sptep, old_spte);
697 else
698 __kvm_tdp_mmu_write_spte(sptep, new_spte);
699 return ret;
700 }
701
702 /*
703 * tdp_mmu_set_spte_atomic - Set a TDP MMU SPTE atomically
704 * and handle the associated bookkeeping. Do not mark the page dirty
705 * in KVM's dirty bitmaps.
706 *
707 * If setting the SPTE fails because it has changed, iter->old_spte will be
708 * refreshed to the current value of the spte.
709 *
710 * @kvm: kvm instance
711 * @iter: a tdp_iter instance currently on the SPTE that should be set
712 * @new_spte: The value the SPTE should be set to
713 * Return:
714 * * 0 - If the SPTE was set.
715 * * -EBUSY - If the SPTE cannot be set. In this case this function will have
716 * no side-effects other than setting iter->old_spte to the last
717 * known value of the spte.
718 */
719 static inline int __must_check tdp_mmu_set_spte_atomic(struct kvm *kvm,
720 struct tdp_iter *iter,
721 u64 new_spte)
722 {
723 u64 *sptep = rcu_dereference(iter->sptep);
724 bool freezed = false;
725
726 /*
727 * The caller is responsible for ensuring the old SPTE is not a REMOVED
728 * SPTE. KVM should never attempt to zap or manipulate a REMOVED SPTE,
729 * and pre-checking before inserting a new SPTE is advantageous as it
730 * avoids unnecessary work.
731 */
732 WARN_ON_ONCE(iter->yielded || is_removed_spte(iter->old_spte));
733
734 lockdep_assert_held_read(&kvm->mmu_lock);
735
736 if (is_private_sptep(iter->sptep) && !is_removed_spte(new_spte)) {
737 int ret;
738
739 if (is_shadow_present_pte(new_spte)) {
740 /*
741 * Populating case. handle_changed_spte() can
742 * process without freezing because it only updates
743 * stats.
744 */
745 ret = set_private_spte_present(kvm, iter->sptep, iter->gfn,
746 iter->old_spte, new_spte, iter->level);
747 if (ret)
748 return ret;
749 } else {
750 /*
751 * Zapping case. handle_changed_spte() calls Secure-EPT
752 * blocking or removal. Freeze the entry.
753 */
754 if (!try_cmpxchg64(sptep, &iter->old_spte, REMOVED_SPTE))
755 return -EBUSY;
756 freezed = true;
757 }
758 } else {
759 /*
760 * Note, fast_pf_fix_direct_spte() can also modify TDP MMU SPTEs
761 * and does not hold the mmu_lock. On failure, i.e. if a
762 * different logical CPU modified the SPTE, try_cmpxchg64()
763 * updates iter->old_spte with the current value, so the caller
764 * operates on fresh data, e.g. if it retries
765 * tdp_mmu_set_spte_atomic()
766 */
767 if (!try_cmpxchg64(sptep, &iter->old_spte, new_spte))
768 return -EBUSY;
769 }
770
771 handle_changed_spte(kvm, iter->as_id, iter->gfn, iter->old_spte,
772 new_spte, sptep_to_sp(sptep)->role, true);
773 if (freezed)
> 774 __kvm_tdp_mmu_write_spte(sptep, new_spte);
775 return 0;
776 }
777
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
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