• Chunyu Hu's avatar
    tracing: Fix kmemleak in tracing_map_array_free() · 475bb3c6
    Chunyu Hu authored
    kmemleak reported the below leak when I was doing clear of the hist
    trigger. With this patch, the kmeamleak is gone.
    
    unreferenced object 0xffff94322b63d760 (size 32):
      comm "bash", pid 1522, jiffies 4403687962 (age 2442.311s)
      hex dump (first 32 bytes):
        00 01 00 00 04 00 00 00 08 00 00 00 ff 00 00 00  ................
        10 00 00 00 00 00 00 00 80 a8 7a f2 31 94 ff ff  ..........z.1...
      backtrace:
        [<ffffffff9e96c27a>] kmemleak_alloc+0x4a/0xa0
        [<ffffffff9e424cba>] kmem_cache_alloc_trace+0xca/0x1d0
        [<ffffffff9e377736>] tracing_map_array_alloc+0x26/0x140
        [<ffffffff9e261be0>] kretprobe_trampoline+0x0/0x50
        [<ffffffff9e38b935>] create_hist_data+0x535/0x750
        [<ffffffff9e38bd47>] event_hist_trigger_func+0x1f7/0x420
        [<ffffffff9e38893d>] event_trigger_write+0xfd/0x1a0
        [<ffffffff9e44dfc7>] __vfs_write+0x37/0x170
        [<ffffffff9e44f552>] vfs_write+0xb2/0x1b0
        [<ffffffff9e450b85>] SyS_write+0x55/0xc0
        [<ffffffff9e203857>] do_syscall_64+0x67/0x150
        [<ffffffff9e977ce7>] return_from_SYSCALL_64+0x0/0x6a
        [<ffffffffffffffff>] 0xffffffffffffffff
    unreferenced object 0xffff9431f27aa880 (size 128):
      comm "bash", pid 1522, jiffies 4403687962 (age 2442.311s)
      hex dump (first 32 bytes):
        00 00 8c 2a 32 94 ff ff 00 f0 8b 2a 32 94 ff ff  ...*2......*2...
        00 e0 8b 2a 32 94 ff ff 00 d0 8b 2a 32 94 ff ff  ...*2......*2...
      backtrace:
        [<ffffffff9e96c27a>] kmemleak_alloc+0x4a/0xa0
        [<ffffffff9e425348>] __kmalloc+0xe8/0x220
        [<ffffffff9e3777c1>] tracing_map_array_alloc+0xb1/0x140
        [<ffffffff9e261be0>] kretprobe_trampoline+0x0/0x50
        [<ffffffff9e38b935>] create_hist_data+0x535/0x750
        [<ffffffff9e38bd47>] event_hist_trigger_func+0x1f7/0x420
        [<ffffffff9e38893d>] event_trigger_write+0xfd/0x1a0
        [<ffffffff9e44dfc7>] __vfs_write+0x37/0x170
        [<ffffffff9e44f552>] vfs_write+0xb2/0x1b0
        [<ffffffff9e450b85>] SyS_write+0x55/0xc0
        [<ffffffff9e203857>] do_syscall_64+0x67/0x150
        [<ffffffff9e977ce7>] return_from_SYSCALL_64+0x0/0x6a
        [<ffffffffffffffff>] 0xffffffffffffffff
    
    Link: http://lkml.kernel.org/r/1502705898-27571-1-git-send-email-chuhu@redhat.com
    
    Cc: stable@vger.kernel.org
    Fixes: 08d43a5f ("tracing: Add lock-free tracing_map")
    Signed-off-by: 's avatarChunyu Hu <chuhu@redhat.com>
    Signed-off-by: 's avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
    475bb3c6