2023-09-13 00:29:00

by Oliver Sang

[permalink] [raw]
Subject: Re: [PATCH] mm: as the same logic with queue_pages_range



Hello,

kernel test robot noticed "ltp.vma02.fail" on:

commit: 8dfdaf99160833af1a0a4ffef60c94627c77025b ("[PATCH] mm: as the same logic with queue_pages_range")
url: https://github.com/intel-lab-lkp/linux/commits/Edward-AD/mm-as-the-same-logic-with-queue_pages_range/20230906-142110
base: https://git.kernel.org/cgit/linux/kernel/git/akpm/mm.git mm-everything
patch link: https://lore.kernel.org/all/[email protected]/
patch subject: [PATCH] mm: as the same logic with queue_pages_range

in testcase: ltp
version: ltp-x86_64-14c1f76-1_20230715
with following parameters:

disk: 1HDD
test: mm-00/vma02



compiler: gcc-12
test machine: 8 threads 1 sockets Intel(R) Core(TM) i7-7700 CPU @ 3.60GHz (Kaby Lake) with 32G memory

(please refer to attached dmesg/kmsg for entire log/backtrace)




If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-lkp/[email protected]



Running tests.......
<<<test_start>>>
tag=vma02 stime=1694438526
cmdline="vma02"
contacts=""
analysis=exit
<<<test_output>>>
vma02 0 TINFO : pid = 3639 addr = 0x7f5202dd6000
vma02 0 TINFO : start = 0x7f5202dd6000, end = 0x7f5202dd7000
vma02 0 TINFO : start = 0x7f5202dd7000, end = 0x7f5202dd8000
vma02 0 TINFO : start = 0x7f5202dd8000, end = 0x7f5202dd9000
vma02 1 TFAIL : vma02.c:144: >1 unmerged VMAs.
incrementing stop
<<<execution_status>>>
initiation_status="ok"
duration=0 termination_type=exited termination_id=1 corefile=no
cutime=0 cstime=7
<<<test_end>>>
INFO: ltp-pan reported some tests FAIL
LTP Version: 20230516-75-g2e582e743

###############################################################

Done executing testcases.
LTP Version: 20230516-75-g2e582e743
###############################################################




The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20230912/[email protected]



--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki


2023-09-14 02:32:37

by Cyril Hrubis

[permalink] [raw]
Subject: Re: [LTP] [PATCH] mm: as the same logic with queue_pages_range

Hi!
> Running tests.......
> <<<test_start>>>
> tag=vma02 stime=1694438526
> cmdline="vma02"
> contacts=""
> analysis=exit
> <<<test_output>>>
> vma02 0 TINFO : pid = 3639 addr = 0x7f5202dd6000
> vma02 0 TINFO : start = 0x7f5202dd6000, end = 0x7f5202dd7000
> vma02 0 TINFO : start = 0x7f5202dd7000, end = 0x7f5202dd8000
> vma02 0 TINFO : start = 0x7f5202dd8000, end = 0x7f5202dd9000
> vma02 1 TFAIL : vma02.c:144: >1 unmerged VMAs.
> incrementing stop

So the test is reproducer for:

commit 9d8cebd4bcd7c3878462fdfda34bbcdeb4df7ef4
Author: KOSAKI Motohiro <[email protected]>
Date: Fri Mar 5 13:41:57 2010 -0800

mm: fix mbind vma merge problem

Strangely, current mbind() doesn't merge vma with neighbor vma although it's possible.
Unfortunately, many vma can reduce performance...


And what the test does is:

- map 3 continous pages
- popluate
- mbind() first page
- mbind() all three pages
- checks that there is only single VMA for the pages after second
mbind()

--
Cyril Hrubis
[email protected]