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[v2,0/3] mm: kmemleak: Improve vmalloc() false positives for thread stack allocation

Message ID 1495726937-23557-1-git-send-email-catalin.marinas@arm.com
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Series mm: kmemleak: Improve vmalloc() false positives for thread stack allocation | expand

Message

Catalin Marinas May 25, 2017, 3:42 p.m. UTC 
Hi,

This is a follow up from [1] (mm: kmemleak: Treat vm_struct as
alternative reference to vmalloc'ed objects).

The first two patches are just clean-up and refactoring. The third
introduces the kmemleak_vmalloc() API which allows a vmalloc() caller to
keep either the returned pointer or a pointer to vm_struct as a
reference (see the patch description for the implementation details).
The false positives were noticed with alloc_thread_stack_node(),
free_thread_stack() and CONFIG_VMAP_STACK where a per-CPU array is used
to cache the freed thread stacks as vm_struct pointers.

Changes since v1:

- Split the patch into three for easier review
- Only call update_refs() if !color_gray() on the found object, it
  avoids an unnecessary function call

[1] http://lkml.kernel.org/r/1495474514-24425-1-git-send-email-catalin.marinas@arm.com

Catalin Marinas (3):
  mm: kmemleak: Slightly reduce the size of some structures on 64-bit
    architectures
  mm: kmemleak: Factor object reference updating out of scan_block()
  mm: kmemleak: Treat vm_struct as alternative reference to vmalloc'ed
    objects

 Documentation/dev-tools/kmemleak.rst |   1 +
 include/linux/kmemleak.h             |   7 ++
 mm/kmemleak.c                        | 136 +++++++++++++++++++++++++++++------
 mm/vmalloc.c                         |   7 +-
 4 files changed, 123 insertions(+), 28 deletions(-)