GRUB does not work when sb_meta_uuid is set on XFSv5

GRUB does not work when sb_meta_uuid is set on XFSv5

[Marcos Mello]

Background:

Kernel 4.3
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ce748eaa65f2e9392ba82726503c8d994ffd6393

xfsprogs 4.2.0
http://oss.sgi.com/cgi-bin/gitweb.cgi?p=xfs/cmds/xfsprogs.git;a=commit;h=9c4e12fb60c15dc9c5e54041c9679454b42cb23e

I am using Xubuntu 16.04, which has 2.02-beta2 plus XFSv5 patches (1570140,
a139188, d3ffeb9, b6e80c7, ff3c200, 049dcfa) backported.

grub-install verbose output before "xfs_admin -U generate <dev>":

https://paste.fedoraproject.org/388290/

And after:

https://paste.fedoraproject.org/388291/

("-U restore" undoes the change)

Re: GRUB does not work when sb_meta_uuid is set on XFSv5

[Andrei Borzenkov]

could you please file bug report on savannah as this needs attention
before 2.02 release. Thank you.

On Wed, Jul 6, 2016 at 2:36 PM, Marcos Mello <marcosfrm@outlook.com> wrote:
> Background:
>
> Kernel 4.3
> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ce748eaa65f2e9392ba82726503c8d994ffd6393
>
> xfsprogs 4.2.0
> http://oss.sgi.com/cgi-bin/gitweb.cgi?p=xfs/cmds/xfsprogs.git;a=commit;h=9c4e12fb60c15dc9c5e54041c9679454b42cb23e
>
> I am using Xubuntu 16.04, which has 2.02-beta2 plus XFSv5 patches (1570140,
> a139188, d3ffeb9, b6e80c7, ff3c200, 049dcfa) backported.
>
> grub-install verbose output before "xfs_admin -U generate <dev>":
>
> https://paste.fedoraproject.org/388290/
>
> And after:
>
> https://paste.fedoraproject.org/388291/
>
> ("-U restore" undoes the change)
>
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> https://lists.gnu.org/mailman/listinfo/grub-devel

Re: GRUB does not work when sb_meta_uuid is set on XFSv5

[Marcos Mello]

Done.

https://savannah.gnu.org/bugs/index.php?48422

Re: GRUB does not work when sb_meta_uuid is set on XFSv5

[Andrei Borzenkov]

06.07.2016 14:36, Marcos Mello пишет:
> Background:
> 
> Kernel 4.3
> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ce748eaa65f2e9392ba82726503c8d994ffd6393
> 
> xfsprogs 4.2.0
> http://oss.sgi.com/cgi-bin/gitweb.cgi?p=xfs/cmds/xfsprogs.git;a=commit;h=9c4e12fb60c15dc9c5e54041c9679454b42cb23e
> 
> I am using Xubuntu 16.04, which has 2.02-beta2 plus XFSv5 patches (1570140,
> a139188, d3ffeb9, b6e80c7, ff3c200, 049dcfa) backported.
> 
> grub-install verbose output before "xfs_admin -U generate <dev>":
> 

This is due to XFS_SB_FEAT_INCOMPAT_META_UUID bit set. Jan, is it enough
to add this bit to XFS_SB_FEAT_INCOMPAT_SUPPORTED or we need extra code
to support it?

Re: GRUB does not work when sb_meta_uuid is set on XFSv5

[Andrei Borzenkov]

[-- Attachment #1: Type: text/plain, Size: 945 bytes --]

08.07.2016 23:15, Andrei Borzenkov пишет:
> 06.07.2016 14:36, Marcos Mello пишет:
>> Background:
>>
>> Kernel 4.3
>> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ce748eaa65f2e9392ba82726503c8d994ffd6393
>>
>> xfsprogs 4.2.0
>> http://oss.sgi.com/cgi-bin/gitweb.cgi?p=xfs/cmds/xfsprogs.git;a=commit;h=9c4e12fb60c15dc9c5e54041c9679454b42cb23e
>>
>> I am using Xubuntu 16.04, which has 2.02-beta2 plus XFSv5 patches (1570140,
>> a139188, d3ffeb9, b6e80c7, ff3c200, 049dcfa) backported.
>>
>> grub-install verbose output before "xfs_admin -U generate <dev>":
>>
> 
> This is due to XFS_SB_FEAT_INCOMPAT_META_UUID bit set. Jan, is it enough
> to add this bit to XFS_SB_FEAT_INCOMPAT_SUPPORTED or we need extra code
> to support it?
> 
> 

As far as I can tell we do not need any extra support (until we start
actually check metadata UUID).

@Marcos could you test this patch? Works for me.

@Jan any comment?



[-- Attachment #2: xfs-meta_uuid.patch --]
[-- Type: text/x-patch, Size: 1300 bytes --]

From: Andrei Borzenkov <arvidjaar@gmail.com>
Subject: [PATCH] xfs: accept filesystem with meta_uuid

XFS V5 stores UUID in metadata and compares them with superblock UUID.
To allow changing of user-visible UUID it stores original value in new
superblock field (meta_uuid) and sets incompatible flag to indicate that
new field must be used to verify metadata. Our driver currently does not
check metadata UUID so simply accept such filesystem.

---
 grub-core/fs/xfs.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/grub-core/fs/xfs.c b/grub-core/fs/xfs.c
index ca9c0c3..9f66dd6 100644
--- a/grub-core/fs/xfs.c
+++ b/grub-core/fs/xfs.c
@@ -76,8 +76,13 @@ GRUB_MOD_LICENSE ("GPLv3+");
 
 /* incompat feature flags */
 #define XFS_SB_FEAT_INCOMPAT_FTYPE      (1 << 0)        /* filetype in dirent */
+#define XFS_SB_FEAT_INCOMPAT_SPINODES   (1 << 1)        /* sparse inode chunks */
+#define XFS_SB_FEAT_INCOMPAT_META_UUID  (1 << 2)        /* metadata UUID */
+
+/* We do not currently verify metadata UUID so it is safe to read such filesystem */
 #define XFS_SB_FEAT_INCOMPAT_SUPPORTED \
-	(XFS_SB_FEAT_INCOMPAT_FTYPE)
+	(XFS_SB_FEAT_INCOMPAT_FTYPE | \
+	 XFS_SB_FEAT_INCOMPAT_META_UUID)
 
 struct grub_xfs_sblock
 {
-- 
tg: (b524fa2..) u/xfs-meta_uuid (depends on: master)

Re: GRUB does not work when sb_meta_uuid is set on XFSv5

[Marcos Mello]

>  @Marcos could you test this patch? Works for me.

It works here too. Thanks.

https://paste.fedoraproject.org/389736/

Re: GRUB does not work when sb_meta_uuid is set on XFSv5

[Andrei Borzenkov]

10.07.2016 22:15, Marcos Mello пишет:
>>  @Marcos could you test this patch? Works for me.
> 
> It works here too. Thanks.
> 
> https://paste.fedoraproject.org/389736/
> 
Does it also works at boot time (i.e. any issues in accessing this
filesystem)?

Re: GRUB does not work when sb_meta_uuid is set on XFSv5

[Marcos Mello]

> Does it also works at boot time (i.e. any issues in accessing this
> filesystem)?

System boots normally. With and without meta_uuid.

Re: GRUB does not work when sb_meta_uuid is set on XFSv5

[Jan Kara]

On Sun 10-07-16 12:46:43, Andrei Borzenkov wrote:
> 08.07.2016 23:15, Andrei Borzenkov пишет:
> > 06.07.2016 14:36, Marcos Mello пишет:
> >> Background:
> >>
> >> Kernel 4.3
> >> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ce748eaa65f2e9392ba82726503c8d994ffd6393
> >>
> >> xfsprogs 4.2.0
> >> http://oss.sgi.com/cgi-bin/gitweb.cgi?p=xfs/cmds/xfsprogs.git;a=commit;h=9c4e12fb60c15dc9c5e54041c9679454b42cb23e
> >>
> >> I am using Xubuntu 16.04, which has 2.02-beta2 plus XFSv5 patches (1570140,
> >> a139188, d3ffeb9, b6e80c7, ff3c200, 049dcfa) backported.
> >>
> >> grub-install verbose output before "xfs_admin -U generate <dev>":
> >>
> > 
> > This is due to XFS_SB_FEAT_INCOMPAT_META_UUID bit set. Jan, is it enough
> > to add this bit to XFS_SB_FEAT_INCOMPAT_SUPPORTED or we need extra code
> > to support it?
> > 
> > 
> 
> As far as I can tell we do not need any extra support (until we start
> actually check metadata UUID).

Correct. The patch looks good to me.

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

Re: GRUB does not work when sb_meta_uuid is set on XFSv5

[Andrei Borzenkov]

11.07.2016 15:04, Jan Kara пишет:
> On Sun 10-07-16 12:46:43, Andrei Borzenkov wrote:
>> 08.07.2016 23:15, Andrei Borzenkov пишет:
>>> 06.07.2016 14:36, Marcos Mello пишет:
>>>> Background:
>>>>
>>>> Kernel 4.3
>>>> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ce748eaa65f2e9392ba82726503c8d994ffd6393
>>>>
>>>> xfsprogs 4.2.0
>>>> http://oss.sgi.com/cgi-bin/gitweb.cgi?p=xfs/cmds/xfsprogs.git;a=commit;h=9c4e12fb60c15dc9c5e54041c9679454b42cb23e
>>>>
>>>> I am using Xubuntu 16.04, which has 2.02-beta2 plus XFSv5 patches (1570140,
>>>> a139188, d3ffeb9, b6e80c7, ff3c200, 049dcfa) backported.
>>>>
>>>> grub-install verbose output before "xfs_admin -U generate <dev>":
>>>>
>>>
>>> This is due to XFS_SB_FEAT_INCOMPAT_META_UUID bit set. Jan, is it enough
>>> to add this bit to XFS_SB_FEAT_INCOMPAT_SUPPORTED or we need extra code
>>> to support it?
>>>
>>>
>>
>> As far as I can tell we do not need any extra support (until we start
>> actually check metadata UUID).
> 
> Correct. The patch looks good to me.
> 
> 								Honza
> 
Applied. Thank you for review!