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Subject: Possible memory leak via tty_ldisc_try_get
From: Catalin Marinas <catalin.marinas@arm.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: linux-kernel <linux-kernel@vger.kernel.org>
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Organization: ARM Ltd
Date: Fri, 12 Jun 2009 10:21:48 +0100
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Hi Alan,

I noticed you pushed some changes to drivers/char/tty_ldisc.c recently.
I now get about 12 kmemleak reports like below (on an ARM platform):

kmemleak: unreferenced object 0xdfaffd60 (size 32):
  comm "init", pid 1, jiffies 4294937946
  backtrace:
    [<c007b8fc>] kmemleak_alloc+0x14c/0x260
    [<c0079624>] kmem_cache_alloc+0x90/0x98
    [<c0147428>] tty_ldisc_try_get+0x14/0xac
    [<c01475a4>] tty_ldisc_get+0x18/0x40
    [<c0147850>] tty_ldisc_reinit+0x28/0x5c
    [<c01478ac>] tty_ldisc_release+0x28/0x3c
    [<c0143450>] tty_release_dev+0x3cc/0x428
    [<c01434b8>] tty_release+0xc/0x14
    [<c007eb60>] __fput+0x104/0x1c4
    [<c007bb48>] filp_close+0x70/0x7c
    [<c007bbc8>] sys_close+0x74/0xa8
    [<c0022dc0>] ret_fast_syscall+0x0/0x2c
    [<ffffffff>] 0xffffffff

Could you please check whether the code is leaking memory? Let me know
if you need more information.

Thanks.

-- 
Catalin