Re: [gentoo-user] Kernel 3.7.9: Lots of devices are root root rw-------.

[Alan McKinnon]

On 24/02/2013 13:02, Alan Mackenzie wrote:
> On Sun, Feb 24, 2013 at 10:44:19AM +0200, Alan McKinnon wrote:
>> On 23/02/2013 19:18, Alan Mackenzie wrote:
>>> Hi, Gentoo!
>
>>> Just built the new kernel 3.7.9 last night, and it's one of these
>>> "nothing works" situations.
>
> Sorry, I was exaggerating here.  I can work normally as long as I don't
> try to use a peripheral, such as printer, audio, or scanner.  My network
> connection is working OK.
>
>>> It seems the problems are with the device files, whose ownership is set
>>> to "root root" (rather than, e.g., "root audio") and whose permissions
>>> are set to crw------- (rather than the expected crw-rw----).
>
>>> I'm still running udev-171-r10.  This might well make a difference.
>
>>> Needless to say, everything works under kernel 3.6.11.  It would be nice
>>> if there were some mistake in my kernel config.
>
>>> Could somebody help me get this fixed, please.
>
>
>> udev sets ownership and permissions on devices nodes, not the kernel.
>
>> I'd guess your udev setup is incompatible with 3.7.* so let's start with
>> the usual:
>
>> What is your kernel config for the various TMPFS settings in the kernel?
>> (grep TMPFS in .config)
>
> CONFIG_DEVTMPFS=y
> CONFIG_DEVTMPFS_MOUNT=y
> CONFIG_TMPFS=y
> CONFIG_TMPFS_POSIX_ACL=y
> CONFIG_TMPFS_XATTR=y
>
>> What mount options apply to /dev?
>
> On my (working) 3.6.11:
> devtmpfs on /dev type devtmpfs (rw,relatime,size=1988792k,nr_inodes=497198,mode=755)
>
> On my (non-working) 3.7.9:
> devtmpfs on /dev type devtmpfs (rw,relatime,size=1988680k,nr_inodes=497170,mode=755)
>
>> Contents of /etc/fstab?
>
> (Leading comments have been removed.)
>
> #/dev/BOOT              /boot           ext2            noauto,noatime  1 2
> /dev/md6                /               ext3            noatime         0 1
> /dev/sda2               none            swap            sw              0 0
> /dev/sdb2               none            swap            sw              0 0
>
> #/dev/mapper/vg-usr     /usr            ext3            noatime         1 2
> /dev/mapper/vg-usrportage       /usr/portage    ext2            noatime         1 2
> /dev/mapper/vg-usrportagedistfiles /usr/portage/distfiles ext2  noatime         1 2
> /dev/mapper/vg-usrsrc   /usr/src        ext3            noatime         1 2
>
> /dev/mapper/vg-home     /home           ext3            noatime         1 2
> /dev/mapper/vg-opt      /opt            ext3            noatime         1 2
>
> /dev/mapper/vg-var      /var            ext3            noatime         1 2
> /dev/mapper/vg-varspoolmail     /var/spool/mail ext3            noatime         1 2
> /dev/mapper/vg-varspoolnews     /var/spool/news reiserfs        noatime         1 2
> /dev/mapper/vg-vardbpkg         /var/db/pkg     ext3            noatime         1 2
>
> /dev/mapper/vg-iso      /iso            ext2            noatime         1 2
> /dev/mapper/vg-old      /old            ext2            noatime         1 2
> /dev/mapper/vg-vg--backup       /backup         ext2            noatime         1 2
>
> /dev/cdrom              /mnt/cdrom      auto            noauto,ro       0 0
> /dev/fd0                /mnt/floppy     auto            noauto          0 0
>
> # glibc 2.2 and above expects tmpfs to be mounted at /dev/shm for
> # POSIX shared memory (shm_open, shm_unlink).
> # (tmpfs is a dynamically expandable/shrinkable ramdisk, and will
> #  use almost no memory if not populated with files)
> shm                     /dev/shm        tmpfs           nodev,nosuid,noexec     0 0
>
>
>> USE flags that apply to udev?
>
> [ebuild   R    ] sys-fs/udev-171-r10
>     USE="gudev hwdb introspection keymap rule_generator
>     -action_modeswitch -build -debug -edd (-extras) -floppy (-selinux) {-test}"

That all looks quite normal (or, nothing stands out as being unusual).

I suppose your next step is to examine udev's logs where it creates the
various devices.


-- 
Alan McKinnon
alan.mckinnon@×××××.com