Newly allocated objects are more likely to be reported as false
positives. Kmemleak ignores the reporting of objects younger than 5
seconds. However, this age was calculated after the memory scanning
completed which usually takes longer than 5 seconds. This patch
make the minimum object age calculation in relation to the start of the
memory scanning.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Since there is a kernel thread for automatically scanning the memory, it
makes sense for the debug/kmemleak file to only show its findings. This
patch also adds support for "echo scan > debug/kmemleak" to trigger an
intermediate memory scan and eliminates the kmemleak_mutex (scan_mutex
covers all the cases now).
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Because of false positives, the memory scanning thread may print too
much information. This patch changes the scanning thread to only print
the number of newly suspected leaks. Further information can be read
from the /sys/kernel/debug/kmemleak file.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

This is to reduce the number of false positives reported.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

(feature suggested by Sergey Senozhatsky)

Kmemleak needs to track all the memory allocations but some of these
happen before kmemleak is initialised. These are stored in an internal
buffer which may be exceeded in some kernel configurations. This patch
adds a configuration option with a default value of 400 and also removes
the stack dump when the early log buffer is exceeded.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NSergey Senozhatsky <sergey.senozhatsky@mail.by>

Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

This is to avoid the confusion created by the "panic" word.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NPekka Enberg <penberg@cs.helsinki.fi>

Kmemleak allocates memory for pointer tracking and it tries to avoid
using GFP_ATOMIC if the caller doesn't require it. However other gfp
flags may be passed by the caller which aren't required by kmemleak.
This patch filters the gfp flags so that only GFP_KERNEL | GFP_ATOMIC
are used.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NPekka Enberg <penberg@cs.helsinki.fi>

This patch adds the base support for the kernel memory leak
detector. It traces the memory allocation/freeing in a way similar to
the Boehm's conservative garbage collector, the difference being that
the unreferenced objects are not freed but only shown in
/sys/kernel/debug/kmemleak. Enabling this feature introduces an
overhead to memory allocations.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: NPekka Enberg <penberg@cs.helsinki.fi>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>