hugetlbfs: call VM_BUG_ON_PAGE earlier in free_huge_page()
authorYongkai Wu <nic.wuyk@gmail.com>
Fri, 14 Dec 2018 22:17:10 +0000 (14:17 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 14 Dec 2018 23:05:45 +0000 (15:05 -0800)
commit8ace22bce84014957da37e6b8baa49ee81c03366
tree3923e3622950039abbb6318349b2c693d0218289
parentf5a222dc2f0e893cc6b0fa34d421a41ca7dfb72e
hugetlbfs: call VM_BUG_ON_PAGE earlier in free_huge_page()

A stack trace was triggered by VM_BUG_ON_PAGE(page_mapcount(page), page)
in free_huge_page().  Unfortunately, the page->mapping field was set to
NULL before this test.  This made it more difficult to determine the
root cause of the problem.

Move the VM_BUG_ON_PAGE tests earlier in the function so that if they do
trigger more information is present in the page struct.

Link: http://lkml.kernel.org/r/1543491843-23438-1-git-send-email-nic_w@163.com
Signed-off-by: Yongkai Wu <nic_w@163.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/hugetlb.c