From 4d45e75a9955ade5c2f49bd96fc4173b2cec9a72 Mon Sep 17 00:00:00 2001 From: Jann Horn Date: Thu, 15 Oct 2020 20:13:00 -0700 Subject: mm: remove the now-unnecessary mmget_still_valid() hack The preceding patches have ensured that core dumping properly takes the mmap_lock. Thanks to that, we can now remove mmget_still_valid() and all its users. Signed-off-by: Jann Horn Signed-off-by: Andrew Morton Acked-by: Linus Torvalds Cc: Christoph Hellwig Cc: Alexander Viro Cc: "Eric W . Biederman" Cc: Oleg Nesterov Cc: Hugh Dickins Link: http://lkml.kernel.org/r/20200827114932.3572699-8-jannh@google.com Signed-off-by: Linus Torvalds --- mm/mmap.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'mm/mmap.c') diff --git a/mm/mmap.c b/mm/mmap.c index 9fb9f8a233c7..ebb92f5515a1 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2562,7 +2562,7 @@ find_extend_vma(struct mm_struct *mm, unsigned long addr) if (vma && (vma->vm_start <= addr)) return vma; /* don't alter vm_end if the coredump is running */ - if (!prev || !mmget_still_valid(mm) || expand_stack(prev, addr)) + if (!prev || expand_stack(prev, addr)) return NULL; if (prev->vm_flags & VM_LOCKED) populate_vma_page_range(prev, addr, prev->vm_end, NULL); @@ -2588,9 +2588,6 @@ find_extend_vma(struct mm_struct *mm, unsigned long addr) return vma; if (!(vma->vm_flags & VM_GROWSDOWN)) return NULL; - /* don't alter vm_start if the coredump is running */ - if (!mmget_still_valid(mm)) - return NULL; start = vma->vm_start; if (expand_stack(vma, addr)) return NULL; -- cgit v1.2.3-59-g8ed1b