The patch titled Subject: kernel/fork: assert no VMA readers during its destruction has been added to the -mm mm-unstable branch. Its filename is kernel-fork-assert-no-vma-readers-during-its-destruction.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kernel-fork-assert-no-vma-readers-during-its-destruction.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Suren Baghdasaryan <surenb@xxxxxxxxxx> Subject: kernel/fork: assert no VMA readers during its destruction Date: Mon, 27 Feb 2023 09:36:19 -0800 Assert there are no holders of VMA lock for reading when it is about to be destroyed. Link: https://lkml.kernel.org/r/20230227173632.3292573-21-surenb@xxxxxxxxxx Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- --- a/kernel/fork.c~kernel-fork-assert-no-vma-readers-during-its-destruction +++ a/kernel/fork.c @@ -491,6 +491,9 @@ static void vm_area_free_rcu_cb(struct r { struct vm_area_struct *vma = container_of(head, struct vm_area_struct, vm_rcu); + + /* The vma should not be locked while being destroyed. */ + VM_BUG_ON_VMA(rwsem_is_locked(&vma->lock), vma); __vm_area_free(vma); } #endif _ Patches currently in -mm which might be from surenb@xxxxxxxxxx are mm-introduce-config_per_vma_lock.patch mm-move-mmap_lock-assert-function-definitions.patch mm-add-per-vma-lock-and-helper-functions-to-control-it.patch mm-mark-vma-as-being-written-when-changing-vm_flags.patch mm-mmap-move-vma_prepare-before-vma_adjust_trans_huge.patch mm-khugepaged-write-lock-vma-while-collapsing-a-huge-page.patch mm-mmap-write-lock-vmas-in-vma_prepare-before-modifying-them.patch mm-mremap-write-lock-vma-while-remapping-it-to-a-new-address-range.patch mm-write-lock-vmas-before-removing-them-from-vma-tree.patch mm-conditionally-write-lock-vma-in-free_pgtables.patch kernel-fork-assert-no-vma-readers-during-its-destruction.patch mm-mmap-prevent-pagefault-handler-from-racing-with-mmu_notifier-registration.patch mm-introduce-vma-detached-flag.patch mm-introduce-lock_vma_under_rcu-to-be-used-from-arch-specific-code.patch mm-fall-back-to-mmap_lock-if-vma-anon_vma-is-not-yet-set.patch mm-add-fault_flag_vma_lock-flag.patch mm-prevent-do_swap_page-from-handling-page-faults-under-vma-lock.patch mm-prevent-userfaults-to-be-handled-under-per-vma-lock.patch mm-introduce-per-vma-lock-statistics.patch x86-mm-try-vma-lock-based-page-fault-handling-first.patch arm64-mm-try-vma-lock-based-page-fault-handling-first.patch mm-mmap-free-vm_area_struct-without-call_rcu-in-exit_mmap.patch mm-separate-vma-lock-from-vm_area_struct.patch per-vma-locks.patch