Re: [LTP] [PATCH V4 for-6.10/block] loop: Fix a race between loop detach and loop open

Re: [LTP] [PATCH V4 for-6.10/block] loop: Fix a race between loop detach and loop open

[kernel test robot]

Hello,

kernel test robot noticed "ltp.ioctl09.fail" on:

commit: 02ab74c165fb204557fe6cde80eda0633fbc4412 ("[PATCH V4 for-6.10/block] loop: Fix a race between loop detach and loop open")
url: https://github.com/intel-lab-lkp/linux/commits/Gulam-Mohamed/loop-Fix-a-race-between-loop-detach-and-loop-open/20240608-031123
base: https://git.kernel.org/cgit/linux/kernel/git/axboe/linux-block.git for-next
patch link: https://lore.kernel.org/all/20240607190607.17705-1-gulam.mohamed@oracle.com/
patch subject: [PATCH V4 for-6.10/block] loop: Fix a race between loop detach and loop open

in testcase: ltp
version: ltp-x86_64-14c1f76-1_20240608
with following parameters:

	disk: 1HDD
	fs: ext4
	test: syscalls-03/ioctl09



compiler: gcc-13
test machine: 4 threads 1 sockets Intel(R) Core(TM) i3-3220 CPU @ 3.30GHz (Ivy Bridge) with 8G 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 <oliver.sang@intel.com>
| Closes: https://lore.kernel.org/oe-lkp/202406112130.a572f72-oliver.sang@intel.com


Running tests.......
<<<test_start>>>
tag=ioctl09 stime=1717978971
cmdline="ioctl09"
contacts=""
analysis=exit
<<<test_output>>>
tst_test.c:1734: TINFO: LTP version: 20240524-32-ge2c52c5bb
tst_test.c:1618: TINFO: Timeout per run is 0h 02m 30s
tst_device.c:96: TINFO: Found free device 0 '/dev/loop0'
ioctl09.c:48: TPASS: access /sys/block/loop0/loop0p1 succeeds
ioctl09.c:56: TPASS: access /dev/loop0p1 succeeds
ioctl09.c:51: TPASS: access /sys/block/loop0/loop0p2 fails
ioctl09.c:59: TPASS: access /dev/loop0p2 fails
ioctl09.c:48: TPASS: access /sys/block/loop0/loop0p1 succeeds
ioctl09.c:56: TPASS: access /dev/loop0p1 succeeds
ioctl09.c:48: TPASS: access /sys/block/loop0/loop0p2 succeeds
ioctl09.c:56: TPASS: access /dev/loop0p2 succeeds
tst_device.c:263: TWARN: ioctl(/dev/loop0, LOOP_CLR_FD, 0) no ENXIO for too long

Summary:
passed   8
failed   0
broken   0
skipped  0
warnings 1
incrementing stop
<<<execution_status>>>
initiation_status="ok"
duration=3 termination_type=exited termination_id=4 corefile=no
cutime=3 cstime=42
<<<test_end>>>
INFO: ltp-pan reported some tests FAIL
LTP Version: 20240524-32-ge2c52c5bb

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

            Done executing testcases.
            LTP Version:  20240524-32-ge2c52c5bb
       ###############################################################




The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20240611/202406112130.a572f72-oliver.sang@intel.com



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


-- 
Mailing list info: https://lists.linux.it/listinfo/ltp

Re: [LTP] [PATCH V4 for-6.10/block] loop: Fix a race between loop detach and loop open

[Gulam Mohamed via ltp]

Hi,

> -----Original Message-----
> From: kernel test robot <oliver.sang@intel.com>
> Sent: Tuesday, June 11, 2024 8:28 PM
> To: Gulam Mohamed <gulam.mohamed@oracle.com>
> Cc: oe-lkp@lists.linux.dev; lkp@intel.com; linux-block@vger.kernel.org;
> ltp@lists.linux.it; linux-kernel@vger.kernel.org; yukuai1@huaweicloud.com;
> hch@lst.de; axboe@kernel.dk; oliver.sang@intel.com
> Subject: Re: [PATCH V4 for-6.10/block] loop: Fix a race between loop detach
> and loop open
> 
> 
> 
> Hello,
> 
> kernel test robot noticed "ltp.ioctl09.fail" on:
> 
> commit: 02ab74c165fb204557fe6cde80eda0633fbc4412 ("[PATCH V4 for-
> 6.10/block] loop: Fix a race between loop detach and loop open")
> url: https://urldefense.com/v3/__https://github.com/intel-lab-
> lkp/linux/commits/Gulam-Mohamed/loop-Fix-a-race-between-loop-detach-
> and-loop-open/20240608-
> 031123__;!!ACWV5N9M2RV99hQ!Niww5tWxpW_rqqBaG_-
> w8CbDvJjcC6AwSb4gYZL3tS7fUrBcYesefSCbVL8GrWLJ0R8W_jyMsgUDi0HVVA
> _7Fk4$
> base:
> https://urldefense.com/v3/__https://git.kernel.org/cgit/linux/kernel/git/axboe
> /linux-block.git__;!!ACWV5N9M2RV99hQ!Niww5tWxpW_rqqBaG_-
> w8CbDvJjcC6AwSb4gYZL3tS7fUrBcYesefSCbVL8GrWLJ0R8W_jyMsgUDi0HVSM
> 8EomQ$  for-next patch link:
> https://urldefense.com/v3/__https://lore.kernel.org/all/20240607190607.177
> 05-1-
> gulam.mohamed@oracle.com/__;!!ACWV5N9M2RV99hQ!Niww5tWxpW_rqq
> BaG_-
> w8CbDvJjcC6AwSb4gYZL3tS7fUrBcYesefSCbVL8GrWLJ0R8W_jyMsgUDi0HVEcY
> Yz3s$
> patch subject: [PATCH V4 for-6.10/block] loop: Fix a race between loop detach
> and loop open
> 
> in testcase: ltp
> version: ltp-x86_64-14c1f76-1_20240608
> with following parameters:
> 
> 	disk: 1HDD
> 	fs: ext4
> 	test: syscalls-03/ioctl09
> 
> 
> 
> compiler: gcc-13
> test machine: 4 threads 1 sockets Intel(R) Core(TM) i3-3220 CPU @ 3.30GHz
> (Ivy Bridge) with 8G 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 <oliver.sang@intel.com>
> | Closes:
> | https://urldefense.com/v3/__https://lore.kernel.org/oe-lkp/20240611213
> | 0.a572f72-
> oliver.sang@intel.com__;!!ACWV5N9M2RV99hQ!Niww5tWxpW_rqqBaG_
> | -
> w8CbDvJjcC6AwSb4gYZL3tS7fUrBcYesefSCbVL8GrWLJ0R8W_jyMsgUDi0HVDgL
> 6MVc$
> 
> 
> Running tests.......
> <<<test_start>>>
> tag=ioctl09 stime=1717978971
> cmdline="ioctl09"
> contacts=""
> analysis=exit
> <<<test_output>>>
> tst_test.c:1734: TINFO: LTP version: 20240524-32-ge2c52c5bb
> tst_test.c:1618: TINFO: Timeout per run is 0h 02m 30s
> tst_device.c:96: TINFO: Found free device 0 '/dev/loop0'
> ioctl09.c:48: TPASS: access /sys/block/loop0/loop0p1 succeeds
> ioctl09.c:56: TPASS: access /dev/loop0p1 succeeds
> ioctl09.c:51: TPASS: access /sys/block/loop0/loop0p2 fails
> ioctl09.c:59: TPASS: access /dev/loop0p2 fails
> ioctl09.c:48: TPASS: access /sys/block/loop0/loop0p1 succeeds
> ioctl09.c:56: TPASS: access /dev/loop0p1 succeeds
> ioctl09.c:48: TPASS: access /sys/block/loop0/loop0p2 succeeds
> ioctl09.c:56: TPASS: access /dev/loop0p2 succeeds
> tst_device.c:263: TWARN: ioctl(/dev/loop0, LOOP_CLR_FD, 0) no ENXIO for
> too long
> 
> Summary:
> passed   8
> failed   0
> broken   0
> skipped  0
> warnings 1
> incrementing stop
> <<<execution_status>>>
> initiation_status="ok"
> duration=3 termination_type=exited termination_id=4 corefile=no
> cutime=3 cstime=42
> <<<test_end>>>
> INFO: ltp-pan reported some tests FAIL
> LTP Version: 20240524-32-ge2c52c5bb
> 
> 
> ###############################################################
> 
>             Done executing testcases.
>             LTP Version:  20240524-32-ge2c52c5bb
> 
> ###############################################################
> 
> 
> 
> 
> The kernel config and materials to reproduce are available at:
> https://urldefense.com/v3/__https://download.01.org/0day-
> ci/archive/20240611/202406112130.a572f72-
> oliver.sang@intel.com__;!!ACWV5N9M2RV99hQ!Niww5tWxpW_rqqBaG_-
> w8CbDvJjcC6AwSb4gYZL3tS7fUrBcYesefSCbVL8GrWLJ0R8W_jyMsgUDi0HVsf4L
> rkk$
> 
> 
> 
> --
> 0-DAY CI Kernel Test Service
> https://urldefense.com/v3/__https://github.com/intel/lkp-
> tests/wiki__;!!ACWV5N9M2RV99hQ!Niww5tWxpW_rqqBaG_-
> w8CbDvJjcC6AwSb4gYZL3tS7fUrBcYesefSCbVL8GrWLJ0R8W_jyMsgUDi0HVQRs
> yTxc$

I looked at the LTP test case failure and also the function tst_detach_device_by_fd() which failed. Our kernel patch will defer all the attempts to detach a loop device to the last close, to fix an issue.
The tst_detach_device_by_fd() in LTP test case will open the loop device and repeatedly checks for error code ENXIO. As the new approach, as I mentioned above, will defer the detach to last close and the last close happens *only* when the LTP test function tst_detach_device_by_fd() returns, the test will obviously fail. So, Can you please modify the LTP test case to accommodate the new behaviour of kernel code for loop detach?
Please let us know your comments.

Regards,
Gulam Mohamed.

-- 
Mailing list info: https://lists.linux.it/listinfo/ltp

Re: [LTP] [PATCH V4 for-6.10/block] loop: Fix a race between loop detach and loop open

[hch]

On Thu, Jun 13, 2024 at 09:10:37PM +0000, Gulam Mohamed wrote:
> I looked at the LTP test case failure and also the function tst_detach_device_by_fd() which failed. Our kernel patch will defer all the attempts to detach a loop device to the last close, to fix an issue.
> The tst_detach_device_by_fd() in LTP test case will open the loop device and repeatedly checks for error code ENXIO. As the new approach, as I mentioned above, will defer the detach to last close and the last close happens *only* when the LTP test function tst_detach_device_by_fd() returns, the test will obviously fail. So, Can you please modify the LTP test case to accommodate the new behaviour of kernel code for loop detach?
> Please let us know your comments.

I still think simply setting the rundown state is the better approach..


-- 
Mailing list info: https://lists.linux.it/listinfo/ltp

Re: [LTP] [PATCH V4 for-6.10/block] loop: Fix a race between loop detach and loop open

[Gulam Mohamed via ltp]

Hi Christoph,

> -----Original Message-----
> From: hch@lst.de <hch@lst.de>
> Sent: Friday, June 14, 2024 11:16 AM
> To: Gulam Mohamed <gulam.mohamed@oracle.com>
> Cc: kernel test robot <oliver.sang@intel.com>; oe-lkp@lists.linux.dev;
> lkp@intel.com; linux-block@vger.kernel.org; ltp@lists.linux.it; linux-
> kernel@vger.kernel.org; yukuai1@huaweicloud.com; hch@lst.de;
> axboe@kernel.dk
> Subject: Re: [PATCH V4 for-6.10/block] loop: Fix a race between loop detach
> and loop open
> 
> On Thu, Jun 13, 2024 at 09:10:37PM +0000, Gulam Mohamed wrote:
> > I looked at the LTP test case failure and also the function
> tst_detach_device_by_fd() which failed. Our kernel patch will defer all the
> attempts to detach a loop device to the last close, to fix an issue.
> > The tst_detach_device_by_fd() in LTP test case will open the loop device
> and repeatedly checks for error code ENXIO. As the new approach, as I
> mentioned above, will defer the detach to last close and the last close
> happens *only* when the LTP test function tst_detach_device_by_fd()
> returns, the test will obviously fail. So, Can you please modify the LTP test case
> to accommodate the new behaviour of kernel code for loop detach?
> > Please let us know your comments.
> 
> I still think simply setting the rundown state is the better approach..

Thanks for the review Christoph. I am sending the V5 as you suggested.

Regards,
Gulam Mohamed.


-- 
Mailing list info: https://lists.linux.it/listinfo/ltp