• Nick Piggin's avatar
    hugetlb: fix lockdep error · 46478758
    Nick Piggin authored
    =============================================
    [ INFO: possible recursive locking detected ]
    2.6.26-rc4 #30
    ---------------------------------------------
    heap-overflow/2250 is trying to acquire lock:
     (&mm->page_table_lock){--..}, at: [<c0000000000cf2e8>] .copy_hugetlb_page_range+0x108/0x280
    
    but task is already holding lock:
     (&mm->page_table_lock){--..}, at: [<c0000000000cf2dc>] .copy_hugetlb_page_range+0xfc/0x280
    
    other info that might help us debug this:
    3 locks held by heap-overflow/2250:
     #0:  (&mm->mmap_sem){----}, at: [<c000000000050e44>] .dup_mm+0x134/0x410
     #1:  (&mm->mmap_sem/1){--..}, at: [<c000000000050e54>] .dup_mm+0x144/0x410
     #2:  (&mm->page_table_lock){--..}, at: [<c0000000000cf2dc>] .copy_hugetlb_page_range+0xfc/0x280
    
    stack backtrace:
    Call Trace:
    [c00000003b2774e0] [c000000000010ce4] .show_stack+0x74/0x1f0 (unreliable)
    [c00000003b2775a0] [c0000000003f10e0] .dump_stack+0x20/0x34
    [c00000003b277620] [c0000000000889bc] .__lock_acquire+0xaac/0x1080
    [c00000003b277740...
    46478758
hugetlb.c 33.6 KB