"missing data block" when converting ext4 to btrfs

"missing data block" when converting ext4 to btrfs

[Christian Zangl]

I am on a test VM where I am trying to convert a second disk to btrfs.

The conversion fails with the error missing data block for bytenr 
1048576 (see below).

I couldn't find any information about the error. What can I do to fix this?

$ fsck -f /dev/sdb1
fsck from util-linux 2.35.2
e2fsck 1.45.6 (20-Mar-2020)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
/dev/sdb1: 150510/4194304 files (0.5% non-contiguous), 2726652/16777216 
blocks

$ btrfs-convert /dev/sdb1
create btrfs filesystem:
         blocksize: 4096
         nodesize:  16384
         features:  extref, skinny-metadata (default)
         checksum:  crc32c
creating ext2 image file
ERROR: missing data block for bytenr 1048576
ERROR: failed to create ext2_saved/image: -2
WARNING: an error occurred during conversion, filesystem is partially 
created but not finalized and not mountable

$ uname -a
Linux t-arch 5.7.7-arch1-1 #1 SMP PREEMPT Wed, 01 Jul 2020 14:53:16 
+0000 x86_64 GNU/Linux

$ btrfs --version
btrfs-progs v5.7

Re: "missing data block" when converting ext4 to btrfs

[Qu Wenruo]

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On 2020/7/14 上午3:46, Christian Zangl wrote:
> I am on a test VM where I am trying to convert a second disk to btrfs.
> 
> The conversion fails with the error missing data block for bytenr
> 1048576 (see below).
> 
> I couldn't find any information about the error. What can I do to fix this?
> 
> $ fsck -f /dev/sdb1
> fsck from util-linux 2.35.2
> e2fsck 1.45.6 (20-Mar-2020)
> Pass 1: Checking inodes, blocks, and sizes
> Pass 2: Checking directory structure
> Pass 3: Checking directory connectivity
> Pass 4: Checking reference counts
> Pass 5: Checking group summary information
> /dev/sdb1: 150510/4194304 files (0.5% non-contiguous), 2726652/16777216
> blocks
> 
> $ btrfs-convert /dev/sdb1
> create btrfs filesystem:
>         blocksize: 4096
>         nodesize:  16384
>         features:  extref, skinny-metadata (default)
>         checksum:  crc32c
> creating ext2 image file
> ERROR: missing data block for bytenr 1048576
> ERROR: failed to create ext2_saved/image: -2
> WARNING: an error occurred during conversion, filesystem is partially
> created but not finalized and not mountable

Can btrfs-convert -r rollback the fs?

If you can rollback, would you provide the ext4 fs image?

Thanks,
Qu

> 
> $ uname -a
> Linux t-arch 5.7.7-arch1-1 #1 SMP PREEMPT Wed, 01 Jul 2020 14:53:16
> +0000 x86_64 GNU/Linux
> 
> $ btrfs --version
> btrfs-progs v5.7


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Re: "missing data block" when converting ext4 to btrfs

[Christian Zangl]

On 2020-07-14 08:10, Qu Wenruo wrote:
> 
> 
> On 2020/7/14 上午3:46, Christian Zangl wrote:
>> I am on a test VM where I am trying to convert a second disk to btrfs.
>>
>> The conversion fails with the error missing data block for bytenr
>> 1048576 (see below).
>>
>> I couldn't find any information about the error. What can I do to fix this?
>>
>> $ fsck -f /dev/sdb1
>> fsck from util-linux 2.35.2
>> e2fsck 1.45.6 (20-Mar-2020)
>> Pass 1: Checking inodes, blocks, and sizes
>> Pass 2: Checking directory structure
>> Pass 3: Checking directory connectivity
>> Pass 4: Checking reference counts
>> Pass 5: Checking group summary information
>> /dev/sdb1: 150510/4194304 files (0.5% non-contiguous), 2726652/16777216
>> blocks
>>
>> $ btrfs-convert /dev/sdb1
>> create btrfs filesystem:
>>          blocksize: 4096
>>          nodesize:  16384
>>          features:  extref, skinny-metadata (default)
>>          checksum:  crc32c
>> creating ext2 image file
>> ERROR: missing data block for bytenr 1048576
>> ERROR: failed to create ext2_saved/image: -2
>> WARNING: an error occurred during conversion, filesystem is partially
>> created but not finalized and not mountable
> 
> Can btrfs-convert -r rollback the fs?

No:

$ sudo btrfs-convert -r /dev/sdb1
No valid Btrfs found on /dev/sdb1
ERROR: unable to open ctree
ERROR: rollback failed

If I do `fsck -f /dev/sdb1` I get lots of errors:

t-arch:~$ sudo fsck -f /dev/sdb1
fsck from util-linux 2.35.2
e2fsck 1.45.6 (20-Mar-2020)
Resize inode not valid.  Recreate<y>? yes
Pass 1: Checking inodes, blocks, and sizes
Deleted inode 3681 has zero dtime.  Fix<y>? yes
Inodes that were part of a corrupted orphan linked list found.  Fix<y>? yes
Inode 3744 was part of the orphaned inode list.  FIXED.
Deleted inode 3745 has zero dtime.  Fix<y>? yes
Inode 3747 has INLINE_DATA_FL flag on filesystem without inline data 
support.
Clear<y>? yes
Inode 3748 was part of the orphaned inode list.  FIXED.
Inode 3748 has a extra size (6144) which is invalid
Fix<y>? yes
Inode 3751 is in use, but has dtime set.  Fix<y>? yes
Inode 3751 has imagic flag set.  Clear<y>? yes
Inode 3752 was part of the orphaned inode list.  FIXED.
Inode 3753 was part of the orphaned inode list.  FIXED.
Inode 3754 is in use, but has dtime set.  Fix<y>? yes
Inode 3755 was part of the orphaned inode list.  FIXED.
Inode 3755 has imagic flag set.  Clear ('a' enables 'yes' to all) <y>? yes
Deleted inode 3801 has zero dtime.  Fix ('a' enables 'yes' to all) <y>?
...

> If you can rollback, would you provide the ext4 fs image?

You mean the vmdk from VMware? I do have a backup.

Thanks!

Christian

> 
> Thanks,
> Qu
> 
>>
>> $ uname -a
>> Linux t-arch 5.7.7-arch1-1 #1 SMP PREEMPT Wed, 01 Jul 2020 14:53:16
>> +0000 x86_64 GNU/Linux
>>
>> $ btrfs --version
>> btrfs-progs v5.7
> 

Re: "missing data block" when converting ext4 to btrfs

[Qu Wenruo]

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On 2020/7/14 下午3:58, Christian Zangl wrote:
> On 2020-07-14 08:10, Qu Wenruo wrote:
>>
>>
>> On 2020/7/14 上午3:46, Christian Zangl wrote:
>>> I am on a test VM where I am trying to convert a second disk to btrfs.
>>>
>>> The conversion fails with the error missing data block for bytenr
>>> 1048576 (see below).
>>>
>>> I couldn't find any information about the error. What can I do to fix
>>> this?
>>>
>>> $ fsck -f /dev/sdb1
>>> fsck from util-linux 2.35.2
>>> e2fsck 1.45.6 (20-Mar-2020)
>>> Pass 1: Checking inodes, blocks, and sizes
>>> Pass 2: Checking directory structure
>>> Pass 3: Checking directory connectivity
>>> Pass 4: Checking reference counts
>>> Pass 5: Checking group summary information
>>> /dev/sdb1: 150510/4194304 files (0.5% non-contiguous), 2726652/16777216
>>> blocks
>>>
>>> $ btrfs-convert /dev/sdb1
>>> create btrfs filesystem:
>>>          blocksize: 4096
>>>          nodesize:  16384
>>>          features:  extref, skinny-metadata (default)
>>>          checksum:  crc32c
>>> creating ext2 image file
>>> ERROR: missing data block for bytenr 1048576
>>> ERROR: failed to create ext2_saved/image: -2
>>> WARNING: an error occurred during conversion, filesystem is partially
>>> created but not finalized and not mountable
>>
>> Can btrfs-convert -r rollback the fs?
> 
> No:
> 
> $ sudo btrfs-convert -r /dev/sdb1
> No valid Btrfs found on /dev/sdb1
> ERROR: unable to open ctree
> ERROR: rollback failed
> 
> If I do `fsck -f /dev/sdb1` I get lots of errors:
> 
> t-arch:~$ sudo fsck -f /dev/sdb1
> fsck from util-linux 2.35.2
> e2fsck 1.45.6 (20-Mar-2020)
> Resize inode not valid.  Recreate<y>? yes
> Pass 1: Checking inodes, blocks, and sizes
> Deleted inode 3681 has zero dtime.  Fix<y>? yes
> Inodes that were part of a corrupted orphan linked list found.  Fix<y>? yes
> Inode 3744 was part of the orphaned inode list.  FIXED.
> Deleted inode 3745 has zero dtime.  Fix<y>? yes
> Inode 3747 has INLINE_DATA_FL flag on filesystem without inline data
> support.
> Clear<y>? yes
> Inode 3748 was part of the orphaned inode list.  FIXED.
> Inode 3748 has a extra size (6144) which is invalid
> Fix<y>? yes
> Inode 3751 is in use, but has dtime set.  Fix<y>? yes
> Inode 3751 has imagic flag set.  Clear<y>? yes
> Inode 3752 was part of the orphaned inode list.  FIXED.
> Inode 3753 was part of the orphaned inode list.  FIXED.
> Inode 3754 is in use, but has dtime set.  Fix<y>? yes
> Inode 3755 was part of the orphaned inode list.  FIXED.
> Inode 3755 has imagic flag set.  Clear ('a' enables 'yes' to all) <y>? yes
> Deleted inode 3801 has zero dtime.  Fix ('a' enables 'yes' to all) <y>?
> ...

This sounds like the cause.

As btrfs completely rely on the used space reported from ext*, and if
the fs is corrupted, then a lot of things can go wrong.

> 
>> If you can rollback, would you provide the ext4 fs image?
> 
> You mean the vmdk from VMware? I do have a backup.

Would you mind to run e2fsck on the backup first to see if that's the
problem?

If the fixed fs can not pass btrfs-convert still, would you mind to send
the fs image?

Thanks,
Qu

> 
> Thanks!
> 
> Christian
> 
>>
>> Thanks,
>> Qu
>>
>>>
>>> $ uname -a
>>> Linux t-arch 5.7.7-arch1-1 #1 SMP PREEMPT Wed, 01 Jul 2020 14:53:16
>>> +0000 x86_64 GNU/Linux
>>>
>>> $ btrfs --version
>>> btrfs-progs v5.7
>>
> 


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Re: "missing data block" when converting ext4 to btrfs

[Christian Zangl]

On 2020-07-14 10:09, Qu Wenruo wrote:
> 
> 
> On 2020/7/14 下午3:58, Christian Zangl wrote:
>> On 2020-07-14 08:10, Qu Wenruo wrote:
>>>
>>>
>>> On 2020/7/14 上午3:46, Christian Zangl wrote:
>>>> I am on a test VM where I am trying to convert a second disk to btrfs.
>>>>
>>>> The conversion fails with the error missing data block for bytenr
>>>> 1048576 (see below).
>>>>
>>>> I couldn't find any information about the error. What can I do to fix
>>>> this?
>>>>
>>>> $ fsck -f /dev/sdb1
>>>> fsck from util-linux 2.35.2
>>>> e2fsck 1.45.6 (20-Mar-2020)
>>>> Pass 1: Checking inodes, blocks, and sizes
>>>> Pass 2: Checking directory structure
>>>> Pass 3: Checking directory connectivity
>>>> Pass 4: Checking reference counts
>>>> Pass 5: Checking group summary information
>>>> /dev/sdb1: 150510/4194304 files (0.5% non-contiguous), 2726652/16777216
>>>> blocks
>>>>
>>>> $ btrfs-convert /dev/sdb1
>>>> create btrfs filesystem:
>>>>           blocksize: 4096
>>>>           nodesize:  16384
>>>>           features:  extref, skinny-metadata (default)
>>>>           checksum:  crc32c
>>>> creating ext2 image file
>>>> ERROR: missing data block for bytenr 1048576
>>>> ERROR: failed to create ext2_saved/image: -2
>>>> WARNING: an error occurred during conversion, filesystem is partially
>>>> created but not finalized and not mountable
>>>
>>> Can btrfs-convert -r rollback the fs?
>>
>> No:
>>
>> $ sudo btrfs-convert -r /dev/sdb1
>> No valid Btrfs found on /dev/sdb1
>> ERROR: unable to open ctree
>> ERROR: rollback failed
>>
>> If I do `fsck -f /dev/sdb1` I get lots of errors:
>>
>> t-arch:~$ sudo fsck -f /dev/sdb1
>> fsck from util-linux 2.35.2
>> e2fsck 1.45.6 (20-Mar-2020)
>> Resize inode not valid.  Recreate<y>? yes
>> Pass 1: Checking inodes, blocks, and sizes
>> Deleted inode 3681 has zero dtime.  Fix<y>? yes
>> Inodes that were part of a corrupted orphan linked list found.  Fix<y>? yes
>> Inode 3744 was part of the orphaned inode list.  FIXED.
>> Deleted inode 3745 has zero dtime.  Fix<y>? yes
>> Inode 3747 has INLINE_DATA_FL flag on filesystem without inline data
>> support.
>> Clear<y>? yes
>> Inode 3748 was part of the orphaned inode list.  FIXED.
>> Inode 3748 has a extra size (6144) which is invalid
>> Fix<y>? yes
>> Inode 3751 is in use, but has dtime set.  Fix<y>? yes
>> Inode 3751 has imagic flag set.  Clear<y>? yes
>> Inode 3752 was part of the orphaned inode list.  FIXED.
>> Inode 3753 was part of the orphaned inode list.  FIXED.
>> Inode 3754 is in use, but has dtime set.  Fix<y>? yes
>> Inode 3755 was part of the orphaned inode list.  FIXED.
>> Inode 3755 has imagic flag set.  Clear ('a' enables 'yes' to all) <y>? yes
>> Deleted inode 3801 has zero dtime.  Fix ('a' enables 'yes' to all) <y>?
>> ...
> 
> This sounds like the cause.
> 
> As btrfs completely rely on the used space reported from ext*, and if
> the fs is corrupted, then a lot of things can go wrong.

No, maybe you missed it but I did a fsck before the convert (see above). 
It reported no errors.

Only after the failed btrfs-convert I get the errors.


>>
>>> If you can rollback, would you provide the ext4 fs image?
>>
>> You mean the vmdk from VMware? I do have a backup.
> 
> Would you mind to run e2fsck on the backup first to see if that's the
> problem?

The backup has no fsck issues.

> If the fixed fs can not pass btrfs-convert still, would you mind to send
> the fs image?

How/where would you like me to send it?

Thanks, Christian

> 
> Thanks,
> Qu
> 
>>
>> Thanks!
>>
>> Christian
>>
>>>
>>> Thanks,
>>> Qu
>>>
>>>>
>>>> $ uname -a
>>>> Linux t-arch 5.7.7-arch1-1 #1 SMP PREEMPT Wed, 01 Jul 2020 14:53:16
>>>> +0000 x86_64 GNU/Linux
>>>>
>>>> $ btrfs --version
>>>> btrfs-progs v5.7
>>>
>>
> 

Re: "missing data block" when converting ext4 to btrfs

[Qu Wenruo]

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On 2020/7/14 下午5:33, Christian Zangl wrote:
> On 2020-07-14 10:09, Qu Wenruo wrote:
>>
>>
>> On 2020/7/14 下午3:58, Christian Zangl wrote:
>>> On 2020-07-14 08:10, Qu Wenruo wrote:
>>>>
>>>>
>>>> On 2020/7/14 上午3:46, Christian Zangl wrote:
>>>>> I am on a test VM where I am trying to convert a second disk to btrfs.
>>>>>
>>>>> The conversion fails with the error missing data block for bytenr
>>>>> 1048576 (see below).
>>>>>
>>>>> I couldn't find any information about the error. What can I do to fix
>>>>> this?
>>>>>
>>>>> $ fsck -f /dev/sdb1
>>>>> fsck from util-linux 2.35.2
>>>>> e2fsck 1.45.6 (20-Mar-2020)
>>>>> Pass 1: Checking inodes, blocks, and sizes
>>>>> Pass 2: Checking directory structure
>>>>> Pass 3: Checking directory connectivity
>>>>> Pass 4: Checking reference counts
>>>>> Pass 5: Checking group summary information
>>>>> /dev/sdb1: 150510/4194304 files (0.5% non-contiguous),
>>>>> 2726652/16777216
>>>>> blocks
>>>>>
>>>>> $ btrfs-convert /dev/sdb1
>>>>> create btrfs filesystem:
>>>>>           blocksize: 4096
>>>>>           nodesize:  16384
>>>>>           features:  extref, skinny-metadata (default)
>>>>>           checksum:  crc32c
>>>>> creating ext2 image file
>>>>> ERROR: missing data block for bytenr 1048576
>>>>> ERROR: failed to create ext2_saved/image: -2
>>>>> WARNING: an error occurred during conversion, filesystem is partially
>>>>> created but not finalized and not mountable
>>>>
>>>> Can btrfs-convert -r rollback the fs?
>>>
>>> No:
>>>
>>> $ sudo btrfs-convert -r /dev/sdb1
>>> No valid Btrfs found on /dev/sdb1
>>> ERROR: unable to open ctree
>>> ERROR: rollback failed
>>>
>>> If I do `fsck -f /dev/sdb1` I get lots of errors:
>>>
>>> t-arch:~$ sudo fsck -f /dev/sdb1
>>> fsck from util-linux 2.35.2
>>> e2fsck 1.45.6 (20-Mar-2020)
>>> Resize inode not valid.  Recreate<y>? yes
>>> Pass 1: Checking inodes, blocks, and sizes
>>> Deleted inode 3681 has zero dtime.  Fix<y>? yes
>>> Inodes that were part of a corrupted orphan linked list found. 
>>> Fix<y>? yes
>>> Inode 3744 was part of the orphaned inode list.  FIXED.
>>> Deleted inode 3745 has zero dtime.  Fix<y>? yes
>>> Inode 3747 has INLINE_DATA_FL flag on filesystem without inline data
>>> support.
>>> Clear<y>? yes
>>> Inode 3748 was part of the orphaned inode list.  FIXED.
>>> Inode 3748 has a extra size (6144) which is invalid
>>> Fix<y>? yes
>>> Inode 3751 is in use, but has dtime set.  Fix<y>? yes
>>> Inode 3751 has imagic flag set.  Clear<y>? yes
>>> Inode 3752 was part of the orphaned inode list.  FIXED.
>>> Inode 3753 was part of the orphaned inode list.  FIXED.
>>> Inode 3754 is in use, but has dtime set.  Fix<y>? yes
>>> Inode 3755 was part of the orphaned inode list.  FIXED.
>>> Inode 3755 has imagic flag set.  Clear ('a' enables 'yes' to all)
>>> <y>? yes
>>> Deleted inode 3801 has zero dtime.  Fix ('a' enables 'yes' to all) <y>?
>>> ...
>>
>> This sounds like the cause.
>>
>> As btrfs completely rely on the used space reported from ext*, and if
>> the fs is corrupted, then a lot of things can go wrong.
> 
> No, maybe you missed it but I did a fsck before the convert (see above).
> It reported no errors.
> 
> Only after the failed btrfs-convert I get the errors.
> 
> 
>>>
>>>> If you can rollback, would you provide the ext4 fs image?
>>>
>>> You mean the vmdk from VMware? I do have a backup.
>>
>> Would you mind to run e2fsck on the backup first to see if that's the
>> problem?
> 
> The backup has no fsck issues.
> 
>> If the fixed fs can not pass btrfs-convert still, would you mind to send
>> the fs image?
> 
> How/where would you like me to send it?

Does Google driver work for you?

Thanks,
Qu
> 
> Thanks, Christian
> 
>>
>> Thanks,
>> Qu
>>
>>>
>>> Thanks!
>>>
>>> Christian
>>>
>>>>
>>>> Thanks,
>>>> Qu
>>>>
>>>>>
>>>>> $ uname -a
>>>>> Linux t-arch 5.7.7-arch1-1 #1 SMP PREEMPT Wed, 01 Jul 2020 14:53:16
>>>>> +0000 x86_64 GNU/Linux
>>>>>
>>>>> $ btrfs --version
>>>>> btrfs-progs v5.7
>>>>
>>>
>>
> 


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Re: "missing data block" when converting ext4 to btrfs

[Christian Zangl]

On 2020-07-14 12:10, Qu Wenruo wrote:
> 
> 
> On 2020/7/14 下午5:33, Christian Zangl wrote:
>> On 2020-07-14 10:09, Qu Wenruo wrote:
>>>
>>>
>>> On 2020/7/14 下午3:58, Christian Zangl wrote:
>>>> On 2020-07-14 08:10, Qu Wenruo wrote:
>>>>>
>>>>>
>>>>> On 2020/7/14 上午3:46, Christian Zangl wrote:
>>>>>> I am on a test VM where I am trying to convert a second disk to btrfs.
>>>>>>
>>>>>> The conversion fails with the error missing data block for bytenr
>>>>>> 1048576 (see below).
>>>>>>
>>>>>> I couldn't find any information about the error. What can I do to fix
>>>>>> this?
>>>>>>
>>>>>> $ fsck -f /dev/sdb1
>>>>>> fsck from util-linux 2.35.2
>>>>>> e2fsck 1.45.6 (20-Mar-2020)
>>>>>> Pass 1: Checking inodes, blocks, and sizes
>>>>>> Pass 2: Checking directory structure
>>>>>> Pass 3: Checking directory connectivity
>>>>>> Pass 4: Checking reference counts
>>>>>> Pass 5: Checking group summary information
>>>>>> /dev/sdb1: 150510/4194304 files (0.5% non-contiguous),
>>>>>> 2726652/16777216
>>>>>> blocks
>>>>>>
>>>>>> $ btrfs-convert /dev/sdb1
>>>>>> create btrfs filesystem:
>>>>>>            blocksize: 4096
>>>>>>            nodesize:  16384
>>>>>>            features:  extref, skinny-metadata (default)
>>>>>>            checksum:  crc32c
>>>>>> creating ext2 image file
>>>>>> ERROR: missing data block for bytenr 1048576
>>>>>> ERROR: failed to create ext2_saved/image: -2
>>>>>> WARNING: an error occurred during conversion, filesystem is partially
>>>>>> created but not finalized and not mountable
>>>>>
>>>>> Can btrfs-convert -r rollback the fs?
>>>>
>>>> No:
>>>>
>>>> $ sudo btrfs-convert -r /dev/sdb1
>>>> No valid Btrfs found on /dev/sdb1
>>>> ERROR: unable to open ctree
>>>> ERROR: rollback failed
>>>>
>>>> If I do `fsck -f /dev/sdb1` I get lots of errors:
>>>>
>>>> t-arch:~$ sudo fsck -f /dev/sdb1
>>>> fsck from util-linux 2.35.2
>>>> e2fsck 1.45.6 (20-Mar-2020)
>>>> Resize inode not valid.  Recreate<y>? yes
>>>> Pass 1: Checking inodes, blocks, and sizes
>>>> Deleted inode 3681 has zero dtime.  Fix<y>? yes
>>>> Inodes that were part of a corrupted orphan linked list found.
>>>> Fix<y>? yes
>>>> Inode 3744 was part of the orphaned inode list.  FIXED.
>>>> Deleted inode 3745 has zero dtime.  Fix<y>? yes
>>>> Inode 3747 has INLINE_DATA_FL flag on filesystem without inline data
>>>> support.
>>>> Clear<y>? yes
>>>> Inode 3748 was part of the orphaned inode list.  FIXED.
>>>> Inode 3748 has a extra size (6144) which is invalid
>>>> Fix<y>? yes
>>>> Inode 3751 is in use, but has dtime set.  Fix<y>? yes
>>>> Inode 3751 has imagic flag set.  Clear<y>? yes
>>>> Inode 3752 was part of the orphaned inode list.  FIXED.
>>>> Inode 3753 was part of the orphaned inode list.  FIXED.
>>>> Inode 3754 is in use, but has dtime set.  Fix<y>? yes
>>>> Inode 3755 was part of the orphaned inode list.  FIXED.
>>>> Inode 3755 has imagic flag set.  Clear ('a' enables 'yes' to all)
>>>> <y>? yes
>>>> Deleted inode 3801 has zero dtime.  Fix ('a' enables 'yes' to all) <y>?
>>>> ...
>>>
>>> This sounds like the cause.
>>>
>>> As btrfs completely rely on the used space reported from ext*, and if
>>> the fs is corrupted, then a lot of things can go wrong.
>>
>> No, maybe you missed it but I did a fsck before the convert (see above).
>> It reported no errors.
>>
>> Only after the failed btrfs-convert I get the errors.
>>
>>
>>>>
>>>>> If you can rollback, would you provide the ext4 fs image?
>>>>
>>>> You mean the vmdk from VMware? I do have a backup.
>>>
>>> Would you mind to run e2fsck on the backup first to see if that's the
>>> problem?
>>
>> The backup has no fsck issues.
>>
>>> If the fixed fs can not pass btrfs-convert still, would you mind to send
>>> the fs image?
>>
>> How/where would you like me to send it?
> 
> Does Google driver work for you?

I sent it to you.

Thanks, Christian

> Thanks,
> Qu
>>
>> Thanks, Christian
>>
>>>
>>> Thanks,
>>> Qu
>>>
>>>>
>>>> Thanks!
>>>>
>>>> Christian
>>>>
>>>>>
>>>>> Thanks,
>>>>> Qu
>>>>>
>>>>>>
>>>>>> $ uname -a
>>>>>> Linux t-arch 5.7.7-arch1-1 #1 SMP PREEMPT Wed, 01 Jul 2020 14:53:16
>>>>>> +0000 x86_64 GNU/Linux
>>>>>>
>>>>>> $ btrfs --version
>>>>>> btrfs-progs v5.7
>>>>>
>>>>
>>>
>>
> 

Re: "missing data block" when converting ext4 to btrfs

[Qu Wenruo]

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Hi Christian,

Thanks for your detailed report.

Now we have pinned down the bug, it's a bit overflow for multiplying
unsigned int.

At least not some fundamental design defeat of btrfs-convert.

The fix has been Cced to you, and passed my local test.
Test case has also been submitted.

Thanks again for your help!
Qu


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Re: "missing data block" when converting ext4 to btrfs

[Christian Zangl]

Great! Thanks for finding and fixing the bug!

Christian

On 2020-07-20 14:56, Qu Wenruo wrote:
> Hi Christian,
> 
> Thanks for your detailed report.
> 
> Now we have pinned down the bug, it's a bit overflow for multiplying
> unsigned int.
> 
> At least not some fundamental design defeat of btrfs-convert.
> 
> The fix has been Cced to you, and passed my local test.
> Test case has also been submitted.
> 
> Thanks again for your help!
> Qu
>