From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Friesen Date: Wed, 18 Apr 2012 22:13:08 +0000 Subject: Re: "udevadm info --attribute-walk --path=/block/sda" doesn't show parents Message-Id: <4F8F3C74.7040000@genband.com> List-Id: References: <4F8F3563.9020701@genband.com> In-Reply-To: <4F8F3563.9020701@genband.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: LKML , linux-hotplug@vger.kernel.org On 04/18/2012 03:42 PM, Chris Friesen wrote: > > I have a 2.6.34.10-based kernel with udev-161 (also tested with udevadm from udev-173). > > When I run "udevadm info --attribute-walk --path=/block/sda" it just shows the device > itself, and doesn't walk the whole chain showing the parents. > > Is there anything I can do, or am I caught with a kernel that isn't properly supported? > I'm not subscribed to the hotplug list, so cc'ing me would be appreciated. > > > I don't know what's causing the problem, but I find it suspicious that /sys/block/sda > is a directory rather than a symlink like it is on my 2.6.35.14 laptop. I'm poking > around in the udevadm code now. Looking at the udevadm code led me to the following: On the problematic 2.6.34 machine: root@typhoon-base-unit0:/root> ls -l /sys/dev/block/ lrwxrwxrwx 1 root root 0 Apr 18 14:34 8:0 -> ../../block/sda On my 2.6.35 machine: [cfriesen@blah udev-173]$ ls -l /sys/dev/block/ lrwxrwxrwx. 1 root root 0 Apr 18 15:54 8:0 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda So where do I go from here? Is there a simple kernel change to make my 2.6.34 kernel behave more like the more recent one? Would an older version of udev be able to parse my 2.6.34 /sys directory properly, or do I need to figure out a way to parse /sys manually? Thanks, Chris -- Chris Friesen Software Developer GENBAND chris.friesen@genband.com www.genband.com