[lkp] [ksm] 40e318e509: ltp.ksm01.fail

[lkp] [ksm] 40e318e509: ltp.ksm01.fail

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 1522 bytes --]

FYI, we noticed the below changes on

https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
commit 40e318e509d2c9f3cdb00ef32d2c14b9868af16b ("ksm: introduce ksm_max_page_sharing per page deduplication limit")

We found LKP KSM test case failed for your patch.

=========================================================================================
compiler/kconfig/rootfs/tbox_group/test/testcase:
  gcc-5/x86_64-nfsroot/debian-x86_64-2015-02-07.cgz/vm-lkp-wsx03-4G/mm_functional_positive/otc_kernel_qa-ts_ltp_ddt

commit: 
  77505a33e539477f1fbe5e6136df5b265f39cccf
  40e318e509d2c9f3cdb00ef32d2c14b9868af16b

77505a33e539477f 40e318e509d2c9f3cdb00ef32d 
---------------- -------------------------- 
       fail:runs  %reproduction    fail:runs
           |             |             |    
           :4          100%           4:4     otc_kernel_qa-ts_ltp_ddt.ksm01.fail
           :4          100%           4:4     otc_kernel_qa-ts_ltp_ddt.ksm01_1.fail


vm-lkp-wsx03-4G: qemu-system-x86_64 -enable-kvm -cpu host
Memory: 4G

To reproduce:

        git clone git://git.kernel.org/pub/scm/linux/kernel/git/wfg/lkp-tests.git
        cd lkp-tests
        bin/lkp install job.yaml  # job file is attached in this email
        bin/lkp run     job.yaml


Disclaimer:
Results have been estimated based on internal Intel analysis and are provided
for informational purposes only. Any difference in system hardware or software
design or configuration may affect actual performance.


Thanks,
Ying Huang

[-- Attachment #2: job.yaml --]
[-- Type: text/plain, Size: 3060 bytes --]

---
LKP_SERVER: inn
LKP_CGI_PORT: 80
LKP_CIFS_PORT: 139
testcase: otc_kernel_qa-ts_ltp_ddt
default-monitors:
  wait: activate-monitor
  kmsg: 
  vmstat:
    interval: 10
default-watchdogs:
  oom-killer: 
  watchdog: 
cpufreq_governor: 
model: qemu-system-x86_64 -enable-kvm -cpu host
nr_vm: 4
nr_cpu: 2
memory: 4G
rootfs: debian-x86_64-2015-02-07.cgz
hdd_partitions: "/dev/vda"
swap_partitions: "/dev/vdb"
ssh_base_port: 23640
category: functional
platform: 
cyclic_branch: internal-eywa/master
otc_kernel_qa-ts_ltp_ddt:
  test: mm_functional_positive
enqueue_time: 2016-01-22 21:45:37.423526851 +08:00
branch: linux-devel/devel-catchup-201601221452
commit: 40e318e509d2c9f3cdb00ef32d2c14b9868af16b
queue: bisect
compiler: gcc-5
testbox: vm-lkp-wsx03-4G-2
tbox_group: vm-lkp-wsx03-4G
kconfig: x86_64-nfsroot
id: b5f46bc5f86f783ccc11fabc5847bf6ebf5a03ff
user: lkp
result_root: "/result/otc_kernel_qa-ts_ltp_ddt/mm_functional_positive/vm-lkp-wsx03-4G/debian-x86_64-2015-02-07.cgz/x86_64-nfsroot/gcc-5/40e318e509d2c9f3cdb00ef32d2c14b9868af16b/1"
job_file: "/lkp/scheduled/vm-lkp-wsx03-4G-2/bisect_otc_kernel_qa-ts_ltp_ddt-mm_functional_positive-debian-x86_64-2015-02-07.cgz-x86_64-nfsroot-40e318e509d2c9f3cdb00ef32d2c14b9868af16b-20160122-58016-vbdb3u-1.yaml"
max_uptime: 3600
initrd: "/osimage/debian/debian-x86_64-2015-02-07.cgz"
bootloader_append:
- root=/dev/ram0
- user=lkp
- job=/lkp/scheduled/vm-lkp-wsx03-4G-2/bisect_otc_kernel_qa-ts_ltp_ddt-mm_functional_positive-debian-x86_64-2015-02-07.cgz-x86_64-nfsroot-40e318e509d2c9f3cdb00ef32d2c14b9868af16b-20160122-58016-vbdb3u-1.yaml
- ARCH=x86_64
- kconfig=x86_64-nfsroot
- branch=linux-devel/devel-catchup-201601221452
- commit=40e318e509d2c9f3cdb00ef32d2c14b9868af16b
- BOOT_IMAGE=/pkg/linux/x86_64-nfsroot/gcc-5/40e318e509d2c9f3cdb00ef32d2c14b9868af16b/vmlinuz-4.4.0-09132-g40e318e
- max_uptime=3600
- RESULT_ROOT=/result/otc_kernel_qa-ts_ltp_ddt/mm_functional_positive/vm-lkp-wsx03-4G/debian-x86_64-2015-02-07.cgz/x86_64-nfsroot/gcc-5/40e318e509d2c9f3cdb00ef32d2c14b9868af16b/1
- LKP_SERVER=inn
- |2-


  earlyprintk=ttyS0,115200 systemd.log_level=err
  debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100
  panic=-1 softlockup_panic=1 nmi_watchdog=panic oops=panic load_ramdisk=2 prompt_ramdisk=0
  console=ttyS0,115200 console=tty0 vga=normal

  rw
lkp_initrd: "/lkp/lkp/lkp-x86_64.cgz"
modules_initrd: "/pkg/linux/x86_64-nfsroot/gcc-5/40e318e509d2c9f3cdb00ef32d2c14b9868af16b/modules.cgz"
bm_initrd: "/osimage/deps/debian-x86_64-2015-02-07.cgz/lkp.cgz,/osimage/deps/debian-x86_64-2015-02-07.cgz/run-ipconfig.cgz,/lkp/benchmarks/otc_kernel_qa-ts_ltp_ddt.cgz"
linux_headers_initrd: "/pkg/linux/x86_64-nfsroot/gcc-5/40e318e509d2c9f3cdb00ef32d2c14b9868af16b/linux-headers.cgz"
kernel: "/pkg/linux/x86_64-nfsroot/gcc-5/40e318e509d2c9f3cdb00ef32d2c14b9868af16b/vmlinuz-4.4.0-09132-g40e318e"
dequeue_time: 2016-01-22 21:51:32.350285504 +08:00
job_state: finished
loadavg: 1.91 1.12 0.51 1/113 12484
start_time: '1453470760'
end_time: '1453471194'
version: "/lkp/lkp/.src-20160122-180809"

[-- Attachment #3: reproduce.sh --]
[-- Type: application/x-sh, Size: 63 bytes --]

Re: [lkp] [ksm] 40e318e509: ltp.ksm01.fail

[Andrea Arcangeli]

Hello,

On Mon, Jan 25, 2016 at 11:04:18AM +0800, kernel test robot wrote:
> FYI, we noticed the below changes on
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> commit 40e318e509d2c9f3cdb00ef32d2c14b9868af16b ("ksm: introduce ksm_max_page_sharing per page deduplication limit")
> 
> We found LKP KSM test case failed for your patch.
> 
> =========================================================================================
> compiler/kconfig/rootfs/tbox_group/test/testcase:
>   gcc-5/x86_64-nfsroot/debian-x86_64-2015-02-07.cgz/vm-lkp-wsx03-4G/mm_functional_positive/otc_kernel_qa-ts_ltp_ddt
> 
> commit: 
>   77505a33e539477f1fbe5e6136df5b265f39cccf
>   40e318e509d2c9f3cdb00ef32d2c14b9868af16b
> 
> 77505a33e539477f 40e318e509d2c9f3cdb00ef32d 
> ---------------- -------------------------- 
>        fail:runs  %reproduction    fail:runs
>            |             |             |    
>            :4          100%           4:4     otc_kernel_qa-ts_ltp_ddt.ksm01.fail
>            :4          100%           4:4     otc_kernel_qa-ts_ltp_ddt.ksm01_1.fail

In this case it's one rare case of false positive. The change in the
merging levels is a "feature" not a "bug".

LTP validation math on ksm sysfs levels shall be updated to account
for the runtime value of /sys/kernel/mm/ksm/max_page_sharing which in
turn affects pages_sharing/pages_shared. In fact you could add
validation for the new fields like stable_node_dups and
stable_node_chains on top of the existing verifications on pages_shar*.

For now you should re-run the test after:

    echo 2 >/sys/kernel/mm/ksm/run
    echo 10000000 > /sys/kernel/mm/ksm/max_page_sharing
    echo 1 >/sys/kernel/mm/ksm/run

And then LTP will pass as usual.

Thanks for the greatly valuable regression testing work,
Andrea