Created attachment 350934 [details] emerge --info The following message is displayed after emerging qemu-1.4.1. * Could not set caps on '/usr/libexec/qemu-bridge-helper' due to missing filesystem support. * Make sure you enable XATTR support for 'ext2/ext3' in your kernel. * You might also have to enable the relevant FS_SECURITY option. I have gentoo-sources-3.8.13 with 'CONFIG_EXT4_FS' and 'CONFIG_EXT4_USE_FOR_EXT23' but there is no XATTR option available. It was removed in Linux 3.8 and is now always enabled. Refer to bug URL. qemu-bridge-helper attributes: ls -l /usr/libexec/qemu-bridge-helper -rws--x--x 1 root root 14176 Jun 14 16:05 /usr/libexec/qemu-bridge-helper I have no idea if these attributes are correct. I do use qemu-bridge-helper so I would like to know if this is a real issue.
You want user_xattr as a mount option, I guess. This isn't something you set at kernel compile time.
(In reply to Jeroen Roovers from comment #1) Mounting with user_xattr and re-emerging qemu suppressed the message. Thanks for the tip. The qemu-bridge-helper attributes have changed slightly. I assume they are correct now? getfattr doesn't return anything. ls -l /usr/libexec/qemu-bridge-helper -rwx--x--x 1 root root 14176 Jun 16 01:01 /usr/libexec/qemu-bridge-helper I think the elog message should be suppressed for >=linux-3.8 to avoid confusion. The relevant FS_SECURITY option is still required. Also a message indicating that mounting with user_xattr is needed. This is my first time using extended attributes and I just assumed from the elog message that this was automatic.
I would like to add that in my case mounting with user_xattr is not needed. Only the relevant FS_SECURITY kernel option is required. qemu-bridge-helper now has the correct file mode of 0711. This is confirmed by the fcaps.eclass entry in the dev manual. A file mode of 4711 results when the system is unable to set capabilities.
Looks fine to me. With missing filesystem support, it degrades gracefully.
sounds like the system is working just fine and we just want to add the user_xattr mount tip. default mke2fs includes that, but i guess if you disable it yourself, you'll need to manually re-add it.
I can see now that it does work as intended. What threw me off was the elog message about missing XATTR support which isn't available in >=linux-3.8. I kept thinking that was the reason why fcaps was failing but it was because I didn't have FS_SECURITY enabled. Sorry about that.
http://sources.gentoo.org/eclass/fcaps.eclass?r1=1.7&r2=1.8
