[LU-692] error setting xattrs moving read-only files

• Status: Resolved
• Project: Lustre
• Affects Version/s: Lustre 1.8.6
• Type: Improvement
• Priority: Minor
• Reporter: Ned Bass
• Assignee: Andreas Dilger
• Resolution: Duplicate

Description

When moving (or cp'ing with --preserver=all) read-only files out of a lustre filesystem, errors are produced as follows

% touch /p/lscratcha/bass6/asdf
% chmod 400 /p/lscratcha/bass6/asdf
% mv /p/lscratcha/bass6/asdf /tmp
mv: setting attribute `lustre.lov' for `lustre.lov': Permission denied
mv: setting attribute `lustre.lov' for `lustre.lov': Permission denied

This isn't really a bug, but rather an unfortunate consequence of the design decision to use the 'lustre' namespace for extended attributes. If Lustre instead used the conventional 'system' namespace then the utilities wouldn't try to preserve them and the errors would be avoided. While harmless, the errors do cause some alarm to users who then wonder if their files have been corrupted. It would be nice to handle this more gracefully in future designs.

Comments

[Andreas Dilger]

The root of this issue is that /tmp has gained xattrs, but it isn't happy with the lustre.* attributes. Is this related to read-only files at all? If yes, then it would seem to be an error in the cp/mv utility to try and set the xattrs after the file is changed read-only.

Using the "system." namespace is troublesome, because it cannot be accessed from userspace at all, and this would make it impossible to backup/restore the file layout with tar --xattr. We originally just used the "trusted." namespace (which allows both userspace and kernel xattr access), but it is limited to root only so regular users could not use tar (in RHEL6 or lustre-patched to save/restore xattrs first) to backup/restore their files and maintain striping.

[Ned Bass]

> The root of this issue is that /tmp has gained xattrs, but it isn't happy with the lustre.* attributes.

I should have mentioned the same error occurs if read-only files are moved between different Lustre filesystems as well.

> Is this related to read-only files at all?

Yes, if the file is writeable the lsetxattr() call instead returns EOPNOTSUPP, but the error is not reported back to the user.

% strace -e lsetxattr mv /p/lscratcha/bass6/asdf /tmp
lsetxattr("/tmp/asdf", "lustre.lov", "\xd0\x0b\xd1\x0b\x01\x00\x00\x00\x89\x08\x01\x1b\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x10\x00\x02\x00\x00\x00\x95\x86\xdc\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00^\x00\x00\x00&\xf1\xd7\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xf9\x00\x00", 80, 0) = -1 EOPNOTSUPP (Operation not supported)

[Ned Bass]

Andreas, I noticed on our 2.1 test filesystem the following EAs are set

trusted.lma
trusted.link
trusted.lov
lustre.lov

whereas on 1.8 only lustre.lov is. Are the trusted attributes supposed to be there or is this a regression?

[Andreas Dilger]

I believe that this is a regression, as described in LU-532.

[Build Master (Inactive)]

Integrated in lustre-b1_8 » x86_64,client,el5,inkernel #149
LU-692 ptlrpc: don't LASSERT on larger ptlrpc_body

Johann Lombardi : 1cf716f1521a2beacafd0d24c4deac0c9d7af662
Files :

• lustre/include/lustre/lustre_idl.h
• lustre/utils/wirecheck.c
• lustre/utils/wiretest.c
• lustre/ptlrpc/pack_generic.c
• lustre/ptlrpc/wiretest.c

[Peter Jones]

http://review.whamcloud.com/#change,1584

[Build Master (Inactive)]

Integrated in lustre-b1_8 » x86_64,client,el5,ofa #149
LU-692 ptlrpc: don't LASSERT on larger ptlrpc_body

Johann Lombardi : 1cf716f1521a2beacafd0d24c4deac0c9d7af662
Files :

• lustre/ptlrpc/wiretest.c
• lustre/utils/wirecheck.c
• lustre/ptlrpc/pack_generic.c
• lustre/include/lustre/lustre_idl.h
• lustre/utils/wiretest.c

[Build Master (Inactive)]

Integrated in lustre-b1_8 » x86_64,client,el6,inkernel #149
LU-692 ptlrpc: don't LASSERT on larger ptlrpc_body

Johann Lombardi : 1cf716f1521a2beacafd0d24c4deac0c9d7af662
Files :

• lustre/utils/wirecheck.c
• lustre/ptlrpc/wiretest.c
• lustre/utils/wiretest.c
• lustre/include/lustre/lustre_idl.h
• lustre/ptlrpc/pack_generic.c

[Build Master (Inactive)]

Integrated in lustre-b1_8 » x86_64,server,el5,ofa #149
LU-692 ptlrpc: don't LASSERT on larger ptlrpc_body

Johann Lombardi : 1cf716f1521a2beacafd0d24c4deac0c9d7af662
Files :

• lustre/utils/wirecheck.c
• lustre/ptlrpc/wiretest.c
• lustre/utils/wiretest.c
• lustre/ptlrpc/pack_generic.c
• lustre/include/lustre/lustre_idl.h

[Build Master (Inactive)]

Integrated in lustre-b1_8 » i686,client,el5,inkernel #149
LU-692 ptlrpc: don't LASSERT on larger ptlrpc_body

Johann Lombardi : 1cf716f1521a2beacafd0d24c4deac0c9d7af662
Files :

• lustre/utils/wiretest.c
• lustre/utils/wirecheck.c
• lustre/ptlrpc/wiretest.c
• lustre/include/lustre/lustre_idl.h
• lustre/ptlrpc/pack_generic.c

[Build Master (Inactive)]

Integrated in lustre-b1_8 » i686,client,el5,ofa #149
LU-692 ptlrpc: don't LASSERT on larger ptlrpc_body

Johann Lombardi : 1cf716f1521a2beacafd0d24c4deac0c9d7af662
Files :

• lustre/ptlrpc/wiretest.c
• lustre/include/lustre/lustre_idl.h
• lustre/utils/wirecheck.c
• lustre/utils/wiretest.c
• lustre/ptlrpc/pack_generic.c

[Build Master (Inactive)]

Integrated in lustre-b1_8 » x86_64,server,el5,inkernel #149
LU-692 ptlrpc: don't LASSERT on larger ptlrpc_body

Johann Lombardi : 1cf716f1521a2beacafd0d24c4deac0c9d7af662
Files :

• lustre/utils/wiretest.c
• lustre/ptlrpc/wiretest.c
• lustre/include/lustre/lustre_idl.h
• lustre/ptlrpc/pack_generic.c
• lustre/utils/wirecheck.c

[Build Master (Inactive)]

Integrated in lustre-b1_8 » x86_64,client,ubuntu1004,inkernel #149
LU-692 ptlrpc: don't LASSERT on larger ptlrpc_body

Johann Lombardi : 1cf716f1521a2beacafd0d24c4deac0c9d7af662
Files :

• lustre/ptlrpc/wiretest.c
• lustre/utils/wiretest.c
• lustre/ptlrpc/pack_generic.c
• lustre/include/lustre/lustre_idl.h
• lustre/utils/wirecheck.c

[Build Master (Inactive)]

Integrated in lustre-b1_8 » i686,client,el6,inkernel #149
LU-692 ptlrpc: don't LASSERT on larger ptlrpc_body

Johann Lombardi : 1cf716f1521a2beacafd0d24c4deac0c9d7af662
Files :

• lustre/ptlrpc/pack_generic.c
• lustre/ptlrpc/wiretest.c
• lustre/include/lustre/lustre_idl.h
• lustre/utils/wiretest.c
• lustre/utils/wirecheck.c

[Build Master (Inactive)]

Integrated in lustre-b1_8 » i686,server,el5,ofa #149
LU-692 ptlrpc: don't LASSERT on larger ptlrpc_body

Johann Lombardi : 1cf716f1521a2beacafd0d24c4deac0c9d7af662
Files :

• lustre/ptlrpc/wiretest.c
• lustre/include/lustre/lustre_idl.h
• lustre/utils/wirecheck.c
• lustre/ptlrpc/pack_generic.c
• lustre/utils/wiretest.c

[Build Master (Inactive)]

Integrated in lustre-b1_8 » i686,server,el5,inkernel #149
LU-692 ptlrpc: don't LASSERT on larger ptlrpc_body

Johann Lombardi : 1cf716f1521a2beacafd0d24c4deac0c9d7af662
Files :

• lustre/utils/wirecheck.c
• lustre/utils/wiretest.c
• lustre/include/lustre/lustre_idl.h
• lustre/ptlrpc/pack_generic.c
• lustre/ptlrpc/wiretest.c

[Andreas Dilger]

My mistake - the above patch should have been attributed to LU-694 and not this bug.

[Peter Jones]

Duplicate of LU532