Re: kmemleak false positive?

Dave Jones
2009-06-25T19:32:18Z

On Thu, Jun 25, 2009 at 06:00:02PM +0100, Catalin Marinas wrote:
> On Thu, 2009-06-25 at 11:40 -0400, Dave Jones wrote:
> > Here's another case (with stack scanning on btw) which looks odd..
> >
> > kmemleak: unreferenced object 0xd86ba000 (size 16):
> > kmemleak: comm "init", pid 1, jiffies 4294683556
> > kmemleak: backtrace:
> > kmemleak: [<c04fd8b3>] kmemleak_alloc+0x193/0x2b8
> > kmemleak: [<c04f5e73>] kmem_cache_alloc+0x11e/0x174
> > kmemleak: [<c05cdfdc>] avtab_insertf+0xd6/0x140
> > kmemleak: [<c05ce3d7>] avtab_read_item+0x26a/0x284
> > kmemleak: [<c05ce5a5>] avtab_read+0x82/0xe5
> > kmemleak: [<c05d0618>] policydb_read+0x40c/0x1028
> > kmemleak: [<c05d459d>] security_load_policy+0x57/0x37c
> > kmemleak: [<c05c9995>] sel_write_load+0xb2/0x54a
> > kmemleak: [<c0500186>] vfs_write+0x9f/0x10f
> > kmemleak: [<c05002e1>] sys_write+0x58/0x8d
> > kmemleak: [<c040a8eb>] sysenter_do_call+0x12/0x38
> > kmemleak: [<ffffffff>] 0xffffffff
> >
> > I looked over the SELinux code, and couldn't see an obvious leak.
> > Eric Paris came to the same conclusion.
>
> How long does a memory scanning take (i.e. time cat debug/kmemleak) on
> your platform? Another tweak is to increase MSECS_MIN_AGE to something
> like 1 minute or more. Especially on SMP, some newly allocated objects
> may be in registers and reported as leaks.

0.00user 16.15system 0:33.38elapsed 48%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+158minor)pagefaults 0swaps

This is a VIA C3 with 512MB of RAM.

Dave