kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-10-20 19:23:40 +00:00
Code Issues Releases Packages Activity
No description
1,068,873 commits 117 branches 5,799 tags 5.6 GiB
  • C 96.9%
  • Assembly 0.9%
  • Rust 0.6%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Dev Jain fdba4fbe5e selftests/mm: compaction_test: fix bogus test success on Aarch64 
[ Upstream commit d4202e66a4 ]

Patch series "Fixes for compaction_test", v2.

The compaction_test memory selftest introduces fragmentation in memory
and then tries to allocate as many hugepages as possible. This series
addresses some problems.

On Aarch64, if nr_hugepages == 0, then the test trivially succeeds since
compaction_index becomes 0, which is less than 3, due to no division by
zero exception being raised. We fix that by checking for division by
zero.

Secondly, correctly set the number of hugepages to zero before trying
to set a large number of them.

Now, consider a situation in which, at the start of the test, a non-zero
number of hugepages have been already set (while running the entire
selftests/mm suite, or manually by the admin). The test operates on 80%
of memory to avoid OOM-killer invocation, and because some memory is
already blocked by hugepages, it would increase the chance of OOM-killing.
Also, since mem_free used in check_compaction() is the value before we
set nr_hugepages to zero, the chance that the compaction_index will
be small is very high if the preset nr_hugepages was high, leading to a
bogus test success.

This patch (of 3):

Currently, if at runtime we are not able to allocate a huge page, the test
will trivially pass on Aarch64 due to no exception being raised on
division by zero while computing compaction_index.  Fix that by checking
for nr_hugepages == 0.  Anyways, in general, avoid a division by zero by
exiting the program beforehand.  While at it, fix a typo, and handle the
case where the number of hugepages may overflow an integer.

Link: https://lkml.kernel.org/r/20240521074358.675031-1-dev.jain@arm.com
Link: https://lkml.kernel.org/r/20240521074358.675031-2-dev.jain@arm.com
Fixes: bd67d5c15c ("Test compaction of mlocked memory")
Signed-off-by: Dev Jain <dev.jain@arm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Sri Jayaramappa <sjayaram@akamai.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
History 2024-07-05 09:14:13 +02:00
arch cma: factor out minimum alignment requirement 2024-07-05 09:14:13 +02:00
block blk-iocost: avoid out of bounds shift 2024-05-17 11:50:54 +02:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:22:01 +02:00
crypto crypto: ecrdsa - Fix module auto-load on add_key 2024-06-16 13:39:58 +02:00
Documentation net: ena: Add dynamic recycling mechanism for rx buffers 2024-06-16 13:39:52 +02:00
drivers cma: factor out minimum alignment requirement 2024-07-05 09:14:13 +02:00
fs NFS: Fix READ_PLUS when server doesn't support OP_READ_PLUS 2024-06-16 13:40:01 +02:00
include cma: factor out minimum alignment requirement 2024-07-05 09:14:13 +02:00
init init/main.c: Fix potential static_command_line memory overflow 2024-04-27 17:05:28 +02:00
io_uring io_uring: fail NOP if non-zero op flags is passed in 2024-06-16 13:39:53 +02:00
ipc ipc/sem: Fix dangling sem_array access in semtimedop race 2022-12-08 11:28:45 +01:00
kernel cma: factor out minimum alignment requirement 2024-07-05 09:14:13 +02:00
lib mm/slub, kunit: Use inverted data to corrupt kmem cache 2024-06-16 13:39:16 +02:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm mm/cma: drop incorrect alignment check in cma_init_reserved_mem 2024-07-05 09:14:13 +02:00
net skbuff: introduce skb_pull_data 2024-07-05 09:14:11 +02:00
samples samples/hw_breakpoint: fix building without module unloading 2023-09-23 11:10:01 +02:00
scripts scripts/gdb: fix SB_* constants parsing 2024-06-16 13:39:54 +02:00
security KEYS: trusted: Do not use WARN when encode fails 2024-05-25 16:20:18 +02:00
sound ALSA: timer: Set lower bound of start tick time 2024-06-16 13:39:52 +02:00
tools selftests/mm: compaction_test: fix bogus test success on Aarch64 2024-07-05 09:14:13 +02:00
usr usr/include/Makefile: add linux/nfc.h to the compile-test coverage 2022-02-01 17:27:15 +01:00
virt KVM: Always flush async #PF workqueue when vCPU is being destroyed 2024-04-10 16:18:34 +02:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap mailmap: add Andrej Shadura 2021-10-18 20:22:03 -10:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Daniel Drake to credits 2021-09-21 08:34:58 +03:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS trace: Relocate event helper files 2024-04-10 16:19:24 +02:00
Makefile Linux 5.15.161 2024-06-16 13:40:01 +02:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -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.

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.