1
0
Fork 0
Fork of alistair23 Linux kernel for reMarkable from https://github.com/alistair23/linux
 
 
 
 
 
 
Go to file
Chintan Pandya 86609d3319 mm/slub.c: use jitter-free reference while printing age
When SLUB_DEBUG catches some issues, it prints all the required debug
info.  However, in a few cases where allocation and free of the object
has happened in a very short time, 'age' might be misleading.  See the
example below:

  =============================================================================
  BUG kmalloc-256 (Tainted: G        W  O   ): Poison overwritten
  -----------------------------------------------------------------------------
  ...
  INFO: Allocated in binder_transaction+0x4b0/0x2448 age=731 cpu=3 pid=5314
  ...
  INFO: Freed in binder_free_transaction+0x2c/0x58 age=735 cpu=6 pid=2079
  ...
  Object fffffff14956a870: 6b 6b 6b 6b 6b 6b 6b 6b 67 6b 6b 6b 6b 6b 6b a5  kkkkkkkkgkkkk

In this case, object got freed later but 'age' shows otherwise.  This
could be because, while printing this info, we print allocation traces
first and free traces thereafter.  In between, if we get schedule out or
jiffies increment, (jiffies - t->when) could become meaningless.

Use the jitter free reference to calculate age.

New output will exactly be same.  'age' is still staying with single
jiffies ref in both prints.

Change-Id: I0846565807a4229748649bbecb1ffb743d71fcd8
Link: http://lkml.kernel.org/r/1520492010-19389-1-git-send-email-cpandya@codeaurora.org
Signed-off-by: Chintan Pandya <cpandya@codeaurora.org>
Acked-by: Christoph Lameter <cl@linux.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 21:36:23 -07:00
Documentation Char/Misc patches for 4.17-rc1 2018-04-04 20:07:20 -07:00
LICENSES LICENSES: Add MPL-1.1 license 2018-01-06 10:59:44 -07:00
arch zboot: fix stack protector in compressed boot phase 2018-04-05 21:36:21 -07:00
block Char/Misc patches for 4.17-rc1 2018-04-04 20:07:20 -07:00
certs certs/blacklist_nohashes.c: fix const confusion in certs blacklist 2018-02-21 15:35:43 -08:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2018-04-04 17:11:08 -07:00
drivers Char/Misc patches for 4.17-rc1 2018-04-04 20:07:20 -07:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs fs: don't flush pagecache when expanding block device 2018-04-05 21:36:23 -07:00
include Char/Misc patches for 4.17-rc1 2018-04-04 20:07:20 -07:00
init Merge branch 'syscalls-next' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux 2018-04-02 21:22:12 -07:00
ipc Merge branch 'userns-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2018-04-03 19:15:32 -07:00
kernel Driver core patches for 4.17-rc1 2018-04-04 19:41:45 -07:00
lib lib: fix stall in __bitmap_parselist() 2018-04-05 21:36:21 -07:00
mm mm/slub.c: use jitter-free reference while printing age 2018-04-05 21:36:23 -07:00
net net/9p/client.c: fix potential refcnt problem of trans module 2018-04-05 21:36:23 -07:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-04-03 14:04:18 -07:00
scripts scripts/faddr2line: show the code context 2018-04-05 21:36:21 -07:00
security Merge branch 'userns-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2018-04-03 19:15:32 -07:00
sound Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-04-03 14:04:18 -07:00
tools Char/Misc patches for 4.17-rc1 2018-04-04 20:07:20 -07:00
usr kbuild: rename built-in.o to built-in.a 2018-03-26 02:01:19 +09:00
virt kvm/arm fixes for 4.16, take 2 2018-03-15 21:45:37 +01:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: move include/config/ksym/* to include/ksym/* 2018-03-26 02:01:23 +09:00
.mailmap Merge remote-tracking branch 'spi/topic/samsung' into spi-next 2018-04-02 15:56:32 +01:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS/CREDITS: Drop METAG ARCHITECTURE 2018-03-05 16:34:24 +00:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
MAINTAINERS Char/Misc patches for 4.17-rc1 2018-04-04 20:07:20 -07:00
Makefile Kconfig updates for v4.17 2018-04-03 16:28:01 -07:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.