Re: [PATCH v2] check: Fix fs specfic imports when $FSTYPE!=$OLD_FSTYPE

["Nirjhar Roy (IBM)" <nirjhar.roy.lists@gmail.com>]

On 2/10/25 19:53, Zorro Lang wrote:
> On Thu, Feb 06, 2025 at 11:32:43PM +0530, Nirjhar Roy (IBM) wrote:
>> On 2/1/25 12:05, Zorro Lang wrote:
>>> On Fri, Jan 31, 2025 at 08:24:57AM -0800, Darrick J. Wong wrote:
>>>> On Fri, Jan 31, 2025 at 06:49:50PM +0530, Nirjhar Roy (IBM) wrote:
>>>>> On 1/29/25 21:32, Darrick J. Wong wrote:
>>>>>> On Wed, Jan 29, 2025 at 04:48:10PM +0530, Nirjhar Roy (IBM) wrote:
>>>>>>> On 1/28/25 23:39, Darrick J. Wong wrote:
>>>>>>>> On Tue, Jan 28, 2025 at 05:00:22AM +0000, Nirjhar Roy (IBM) wrote:
>>>>>>>>> Bug Description:
>>>>>>>>>
>>>>>>>>> _test_mount function is failing with the following error:
>>>>>>>>> ./common/rc: line 4716: _xfs_prepare_for_eio_shutdown: command not found
>>>>>>>>> check: failed to mount /dev/loop0 on /mnt1/test
>>>>>>>>>
>>>>>>>>> when the second section in local.config file is xfs and the first section
>>>>>>>>> is non-xfs.
>>>>>>>>>
>>>>>>>>> It can be easily reproduced with the following local.config file
>>>>>>>>>
>>>>>>>>> [s2]
>>>>>>>>> export FSTYP=ext4
>>>>>>>>> export TEST_DEV=/dev/loop0
>>>>>>>>> export TEST_DIR=/mnt1/test
>>>>>>>>> export SCRATCH_DEV=/dev/loop1
>>>>>>>>> export SCRATCH_MNT=/mnt1/scratch
>>>>>>>>>
>>>>>>>>> [s1]
>>>>>>>>> export FSTYP=xfs
>>>>>>>>> export TEST_DEV=/dev/loop0
>>>>>>>>> export TEST_DIR=/mnt1/test
>>>>>>>>> export SCRATCH_DEV=/dev/loop1
>>>>>>>>> export SCRATCH_MNT=/mnt1/scratch
>>>>>>>>>
>>>>>>>>> ./check selftest/001
>>>>>>>>>
>>>>>>>>> Root cause:
>>>>>>>>> When _test_mount() is executed for the second section, the FSTYPE has
>>>>>>>>> already changed but the new fs specific common/$FSTYP has not yet
>>>>>>>>> been done. Hence _xfs_prepare_for_eio_shutdown() is not found and
>>>>>>>>> the test run fails.
>>>>>>>>>
>>>>>>>>> Fix:
>>>>>>>>> Remove the additional _test_mount in check file just before ". commom/rc"
>>>>>>>>> since ". commom/rc" is already sourcing fs specific imports and doing a
>>>>>>>>> _test_mount.
>>>>>>>>>
>>>>>>>>> Fixes: 1a49022fab9b4 ("fstests: always use fail-at-unmount semantics for XFS")
>>>>>>>>> Signed-off-by: Nirjhar Roy (IBM) <nirjhar.roy.lists@gmail.com>
>>>>>>>>> ---
>>>>>>>>>      check | 12 +++---------
>>>>>>>>>      1 file changed, 3 insertions(+), 9 deletions(-)
>>>>>>>>>
>>>>>>>>> diff --git a/check b/check
>>>>>>>>> index 607d2456..5cb4e7eb 100755
>>>>>>>>> --- a/check
>>>>>>>>> +++ b/check
>>>>>>>>> @@ -784,15 +784,9 @@ function run_section()
>>>>>>>>>      			status=1
>>>>>>>>>      			exit
>>>>>>>>>      		fi
>>>>>>>>> -		if ! _test_mount
>>>>>>>> Don't we want to _test_mount the newly created filesystem still?  But
>>>>>>>> perhaps after sourcing common/rc ?
>>>>>>>>
>>>>>>>> --D
>>>>>>> common/rc calls init_rc() in the end and init_rc() already does a
>>>>>>> _test_mount. _test_mount after sourcing common/rc will fail, won't it? Does
>>>>>>> that make sense?
>>>>>>>
>>>>>>> init_rc()
>>>>>>> {
>>>>>>>        # make some further configuration checks here
>>>>>>>        if [ "$TEST_DEV" = ""  ]
>>>>>>>        then
>>>>>>>            echo "common/rc: Error: \$TEST_DEV is not set"
>>>>>>>            exit 1
>>>>>>>        fi
>>>>>>>
>>>>>>>        # if $TEST_DEV is not mounted, mount it now as XFS
>>>>>>>        if [ -z "`_fs_type $TEST_DEV`" ]
>>>>>>>        then
>>>>>>>            # $TEST_DEV is not mounted
>>>>>>>            if ! _test_mount
>>>>>>>            then
>>>>>>>                echo "common/rc: retrying test device mount with external set"
>>>>>>>                [ "$USE_EXTERNAL" != "yes" ] && export USE_EXTERNAL=yes
>>>>>>>                if ! _test_mount
>>>>>>>                then
>>>>>>>                    echo "common/rc: could not mount $TEST_DEV on $TEST_DIR"
>>>>>>>                    exit 1
>>>>>>>                fi
>>>>>>>            fi
>>>>>>>        fi
>>>>>>> ...
>>>>>> ahahahaha yes it does.
>>>>>>
>>>>>> /commit message reading comprehension fail, sorry about that.
>>>>>>
>>>>>> Though now that you point it out, should check elide the init_rc call
>>>>>> about 12 lines down if it re-sourced common/rc ?
>>>>> Yes, it should. init_rc() is getting called twice when common/rc is getting
>>>>> re-sourced. Maybe I can do like
>>>>>
>>>>>
>>>>> if $RECREATE_TEST_DEV || [ "$OLD_FSTYP" != "$FSTYP" ]; then
>>>>>
>>>>>       <...>
>>>>>
>>>>>       . common/rc # changes in this patch
>>>>>
>>>>>       <...>
>>>>>
>>>>> elif [ "$OLD_TEST_FS_MOUNT_OPTS" != "$TEST_FS_MOUNT_OPTS" ]; then
>>>>>
>>>>>       ...
>>>>>
>>>>>       init_rc() # explicitly adding an init_rc() for this condition
>>>>>
>>>>> else
>>>>>
>>>>>       init_rc() # # explicitly adding an init_rc() for all other conditions.
>>>>> This will prevent init_rc() from getting called twice during re-sourcing
>>>>> common/rc
>>>>>
>>>>> fi
>>>>>
>>>>> What do you think?
>>>> Sounds fine as a mechanical change, but I wonder, should calling init_rc
>>>> be explicit?  There are not so many places that source common/rc:
>>>>
>>>> $ git grep 'common/rc'
>>>> check:362:if ! . ./common/rc; then
>>>> check:836:              . common/rc
>>>> common/preamble:52:     . ./common/rc
>>>> soak:7:. ./common/rc
>>>> tests/generic/749:18:. ./common/rc
>>>>
>>>> (I filtered out the non-executable matches)
>>>>
>>>> I think the call in generic/749 is unnecessary and I don't know what
>>>> soak does.  But that means that one could insert an explicit call to
>>>> init_rc at line 366 and 837 in check and at line 53 in common/preamble,
>>>> and we can clean up one more of those places where sourcing a common/
>>>> file actually /does/ something quietly under the covers.
>>>>
>>>> (Unless the maintainer is ok with the status quo...?)
>>> I think people just hope to import the helpers in common/rc mostly, don't
>>> want to run init_rc again. Maybe we can make sure the init_rc is only run
>>> once each time?
>>>
>>> E.g.
>>>
>>>     if [ _INIT_RC != "done" ];then
>>> 	init_rc
>>> 	_INIT_RC="done"
>>>     fi
>>>
>>> Or any better idea.
>> Yes, this idea looks good too. However, after thinking a bit more, I like
>> Darrick's idea to remove the call to init_rc from common/rc and explicitly
>> calling them explicitly whenever necessary makes more sense. This also makes
>> the interface/reason to source common/rc more meaningful, and also not
>> making common/rc do something via init_rc silently. What do you think?
> Sorry I'm on a travel, reply you late. I don't like to run codes in include
> files either :) If we remove the init_rc calling from common/rc we might
> need to do 2 things:
> 1) xfstests/check needs to run init_rc, calls it in check properly.
> 2) Now each sub-cases run init_rc when they import common/rc, I think
> we can call init_rc in common/preamble:_begin_fstest().

Sorry for my delayed reply, I got caught up with some other work items. 
Thank you for your above suggestions. Let me go through them, look for 
some edge cases and I can come up with a patch after some proper testing.

Regards,

--NR

>
> If I miss other things, please feel free to remind me:)
>
> Thanks,
> Zorro
>
>> --NR
>>
>>> Thanks,
>>> Zorro
>>>
>>>> --D
>>>>
>>>>>> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
>>>>>>
>>>>>> --D
>>>>>>
>>>>>>> ...
>>>>>>>
>>>>>>> --NR
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>> -		then
>>>>>>>>> -			echo "check: failed to mount $TEST_DEV on $TEST_DIR"
>>>>>>>>> -			status=1
>>>>>>>>> -			exit
>>>>>>>>> -		fi
>>>>>>>>> -		# TEST_DEV has been recreated, previous FSTYP derived from
>>>>>>>>> -		# TEST_DEV could be changed, source common/rc again with
>>>>>>>>> -		# correct FSTYP to get FSTYP specific configs, e.g. common/xfs
>>>>>>>>> +		# Previous FSTYP derived from TEST_DEV could be changed, source
>>>>>>>>> +		# common/rc again with correct FSTYP to get FSTYP specific configs,
>>>>>>>>> +		# e.g. common/xfs
>>>>>>>>>      		. common/rc
>>>>>>>>>      		_prepare_test_list
>>>>>>>>>      	elif [ "$OLD_TEST_FS_MOUNT_OPTS" != "$TEST_FS_MOUNT_OPTS" ]; then
>>>>>>>>> -- 
>>>>>>>>> 2.34.1
>>>>>>>>>
>>>>>>>>>
>>>>>>> -- 
>>>>>>> Nirjhar Roy
>>>>>>> Linux Kernel Developer
>>>>>>> IBM, Bangalore
>>>>>>>
>>>>> -- 
>>>>> Nirjhar Roy
>>>>> Linux Kernel Developer
>>>>> IBM, Bangalore
>>>>>
>>>>>
>> -- 
>> Nirjhar Roy
>> Linux Kernel Developer
>> IBM, Bangalore
>>
-- 
Nirjhar Roy
Linux Kernel Developer
IBM, Bangalore