linux-kernel - [PATCH 0/4] Add free() function

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20180322195819.24271-1-willy@infradead.org>
Date:   Thu, 22 Mar 2018 12:58:15 -0700
From:   Matthew Wilcox <willy@...radead.org>
To:     linux-mm@...ck.org
Cc:     Kirill Tkhai <ktkhai@...tuozzo.com>,
        Matthew Wilcox <mawilcox@...rosoft.com>,
        linux-kernel@...r.kernel.org,
        "Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>
Subject: [PATCH 0/4] Add free() function

From: Matthew Wilcox <mawilcox@...rosoft.com>

Today, kfree_rcu() can only free objects allocated using kmalloc().
There have been attempts to extend that to kvfree(), but I think we
should take it even further and allow freeing as many different objects
as possible.

It turns out many different kinds of memory allocations can be detected
from the address.  vmalloc() and percpu_alloc() can be detected by being
in a particular range.  kmalloc() and kmem_cache_alloc() can be detected
from the struct page.  __get_free_pages() and page_frag_alloc() are both
freeable just by decrementing the refcount on the page.

This allows us to delete many dozens of tiny rcu callbacks throughout
the kernel, much as was done when kfree_rcu was added.

Matthew Wilcox (4):
  decompression: Rename malloc and free
  Rename 'free' functions
  mm: Add free()
  rcu: Switch to using free() instead of kfree()

 crypto/lrw.c                  |  4 ++--
 crypto/xts.c                  |  4 ++--
 include/linux/decompress/mm.h | 10 ++++++----
 include/linux/kernel.h        |  2 ++
 include/linux/rcupdate.h      | 40 +++++++++++++++++++---------------------
 include/linux/rcutiny.h       |  2 +-
 include/linux/rcutree.h       |  2 +-
 include/trace/events/rcu.h    |  8 ++++----
 kernel/rcu/rcu.h              |  8 +++-----
 kernel/rcu/tree.c             | 11 +++++------
 mm/util.c                     | 39 +++++++++++++++++++++++++++++++++++++++
 11 files changed, 84 insertions(+), 46 deletions(-)

-- 
2.16.2