Red Hat Bugzilla – Bug 135171
Access to /proc/bus/usb/devices hangs the kernel
Last modified: 2007-11-30 17:10:51 EST
Description of problem:
At any point after a USB timeout occurs (as they tend to do plugging
USB devices file access hang the system deadlocked on a semaphore.
This has horrible consequences
One test setup shows this during boot up so Anaconda hangs and you
A second shows it when the monitor (with USB hub) powers down. After
that anything touching the USB devices file hangs the box.
Thirdly you can cause it to order as a user by inserting and quickly
removing a device, killing the hal layer and rendering the box
unusable without even having login access to it.
This bug appears to have arrived between 2.6.6 and 2.6.7 somewhere.
This also btw seems to cause some of the kudzu hangs people see.
Can you reproduce with .603, or even BK head?
Its present in current 2.6.9-rc snapshots too. Came in between 2.6.6
and 2.6.7 somewhere.
Done some more digging
I cannot reproduce this with 18.104.22.168 vanilla, only various RH builds
so it looks like something that is specific to our tree. WIll test
.603 for completeness
*** Bug 134026 has been marked as a duplicate of this bug. ***
Propogating block from dup
541 has the buggy change - 624 is ok