Michal Hocko <mhocko@xxxxxxxxxx> wrote: > Hmm, I do not see this neither in linux-mm nor LKML. Strange > > On Wed 23-08-17 14:41:21, Andrew Morton wrote: >> From: Eric Biggers <ebiggers@xxxxxxxxxx> >> Subject: mm/madvise.c: fix freeing of locked page with MADV_FREE >> >> If madvise(..., MADV_FREE) split a transparent hugepage, it called >> put_page() before unlock_page(). This was wrong because put_page() can >> free the page, e.g. if a concurrent madvise(..., MADV_DONTNEED) has >> removed it from the memory mapping. put_page() then rightfully complained >> about freeing a locked page. >> >> Fix this by moving the unlock_page() before put_page(). Quick grep shows that a similar flow (put_page() followed by an unlock_page() ) also happens in hugetlbfs_fallocate(). Isn’t it a problem as well?