Re: f2fs bug: Unable to mount big volumes in kernel 4.5

[Jaegeuk Kim <jaegeuk@kernel.org>]

On Mon, Mar 21, 2016 at 10:58:49AM +0100, Matthias Prager wrote:
> Am 21.03.2016 um 04:18 schrieb Chao Yu:
> > Hi all,
> > 
> >> -----Original Message-----
> >> From: Jaegeuk Kim [mailto:jaegeuk@kernel.org]
> >> Sent: Monday, March 21, 2016 6:47 AM
> >> To: David Gnedt
> >> Cc: Chao Yu
> >> Subject: Re: f2fs bug: Unable to mount big volumes in kernel 4.5
> >>
> >> Hello,
> >>
> >> As you pointed out, it seems there is a bug in sanity check routine, which
> >> doesn't cover the large section case.
> > 
> > Actually, there is a bug in f2fs-tools 1.6.0, it will trigger sanity check failure
> > in f2fs kernel module since in mkfs.f2fs we will align segment_count and
> > segment_count_main with different size if parameter -s or -z is configured larger
> > than 1.
> > 
> > Following commit in dev branch of f2fs-tools has fixed this issue, could you test this
> > patch firstly?
> > ("mkfs.f2fs: set segment_count in super block correctly")
> I just did (with an unpatched 4.5.0 kernel) and with this f2f2-tools
> patch applied a newly created fs with '-s 9' does mount without errors.
> 
> There seem to be quite a few interesting commits in the f2fs-tools dev
> tree. Is a new release of f2fs-tools planned soon?

Hope to release v1.7.0 in the next month, which will introduce resize.f2fs and
sload.f2fs.
I'm waiting for rolling out products shipped by the tools.

Thanks,

> 
> > 
> > Thanks,
> > 
> >>
> >> Could you test the attached patch?
> >>
> >> Thanks,
> >>
> >> On Sun, Mar 20, 2016 at 04:53:10PM +0100, David Gnedt wrote:
> >>> Hello,
> >>>
> >>> I have a problem with mounting a very big f2fs volume (8TB Seagate SMR drive) in
> >>> kernel 4.5. It works without any problems in 4.4.6, but with 4.5 I get errors
> >>> during mount (see attached file smr_log.txt).
> >>>
> >>> I have created the volume with f2fs-tools 1.6.0 and also a fsck works without
> >>> any problems (see attached file smr_fsck.txt).
> >>>
> >>> I suspect the following commit to be the cause:
> >>>
> >>> commit 9a59b62fd88196844cee5fff851bee2cfd7afb6e
> >>> f2fs: do more integrity verification for superblock
> >>>
> >>>
> >> https://git.kernel.org/cgit/linux/kernel/git/jaegeuk/f2fs.git/commit/fs/f2fs/super.c?id=9a
> >> 59b62fd88196844cee5fff851bee2cfd7afb6e
> >>>
> >>> I haven't had time to dig deeper, but my guess is that the volume is too big, so
> >>> that the 32bit integers overflow during the new check routine
> >>> sanity_check_area_boundary().
> >>>
> >>> Please let me know, if you need any more information. F2fs is currently the only
> >>> filesystem that really works on those SMR drives, therefore it is an important
> >>> issue to me.
> >>>
> >>> Best regards,
> >>> David Gnedt
> >>
> >>> [437136.843299] F2FS-fs (dm-7): Wrong MAIN_AREA boundary, start(4063232) end(1953505792)
> >> blocks(1949433856)
> >>> [437136.843302] F2FS-fs (dm-7): Can't find valid F2FS filesystem in 1th superblock
> >>> [437136.843418] F2FS-fs (dm-7): Wrong MAIN_AREA boundary, start(4063232) end(1953505792)
> >> blocks(1949433856)
> >>> [437136.843419] F2FS-fs (dm-7): Can't find valid F2FS filesystem in 2th superblock
> >>> [437136.843420] F2FS-fs (dm-7): Wrong MAIN_AREA boundary, start(4063232) end(1953505792)
> >> blocks(1949433856)
> >>> [437136.843421] F2FS-fs (dm-7): Can't find valid F2FS filesystem in 1th superblock
> >>> [437136.843422] F2FS-fs (dm-7): Wrong MAIN_AREA boundary, start(4063232) end(1953505792)
> >> blocks(1949433856)
> >>> [437136.843422] F2FS-fs (dm-7): Can't find valid F2FS filesystem in 2th superblock
> >>
> >>> Info: sector size = 512
> >>> Info: total sectors = 15628046336 (7630882 MB)
> >>> Info: MKFS version
> >>>   "Linux version 4.4.0-040400-generic (kernel@gomeisa) (gcc version 5.2.1 20151010 (Ubuntu
> >> 5.2.1-22ubuntu2) ) #201601101930 SMP Mon Jan 11 00:32:41 UTC 2016"
> >>> Info: FSCK version
> >>>   from "Linux version 4.4.0-040400-generic (kernel@gomeisa) (gcc version 5.2.1 20151010
> >> (Ubuntu 5.2.1-22ubuntu2) ) #201601101930 SMP Mon Jan 11 00:32:41 UTC 2016"
> >>>     to "Linux version 4.5.0-040500-generic (kernel@tangerine) (gcc version 5.2.1 20151010
> >> (Ubuntu 5.2.1-22ubuntu2) ) #201603140130 SMP Mon Mar 14 05:32:22 UTC 2016"
> >>> Info: superblock features = 0 :
> >>> Info: superblock encrypt level = 0, salt = 00000000000000000000000000000000
> >>> Info: total FS sectors = 15628046336 (7630882 MB)
> >>> Info: CKPT version = 122a
> >>> Info: checkpoint state = 1 :  unmount
> >>>
> >>> [FSCK] Unreachable nat entries                        [Ok..] [0x0]
> >>> [FSCK] SIT valid block bitmap checking                [Ok..]
> >>> [FSCK] Hard link checking for regular file            [Ok..] [0x0]
> >>> [FSCK] valid_block_count matching with CP             [Ok..] [0x57cea239]
> >>> [FSCK] valid_node_count matcing with CP (de lookup)   [Ok..] [0x61b3bd]
> >>> [FSCK] valid_node_count matcing with CP (nat lookup)  [Ok..] [0x61b3bd]
> >>> [FSCK] valid_inode_count matched with CP              [Ok..] [0x4c0a61]
> >>> [FSCK] free segment_count matched with CP             [Ok..] [0xe31ac]
> >>> [FSCK] next block offset is free                      [Ok..]
> >>> [FSCK] fixing SIT types
> >>> [FSCK] other corrupted bugs                           [Ok..]
> >>>
> >>> Done.
> > 

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