Red Hat Bugzilla – Bug 163302
md5sum hangs system on bad CD
Last modified: 2015-01-04 17:20:51 EST
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User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.8) Gecko/20050513 Epiphany/1.6.1
Description of problem:
I was testing burning CDs with GNOME Nautilus, a very unreliable process in my experience. To check if the resultant CD was good I ran "md5sum /dev/cdrom" and after 20s my system locked up completely!
After resetting I checked /var/log/messages which showed:
kernel: cdrom: This disc doesn't have any tracks I recognize!
kernel: scsi: unknown opcode 0x01
When I ran "md5sum /dev/cdrom" on FC3 on the same computer I got:
md5sum: /dev/cdrom Input/output error
which is what I'd expect for a bad CD.
Note that, althought burning through GNOME is unreliable I can burn fine with cdrecord. That and the fact that this check works OK on FC3 leads me to assert that there isn't a hardware problem.
I also think that, despite encountering this problem with one CD only so far (I've only tried to burn one with GNOME on FC4 so far) the fact that such md5sum ran as a user can take a system out indicates a serious problem.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Insert my bad CD into the CD drive.
2. Run "md5sum /dev/cdrom" from the GNOME terminal.
Actual Results: Some CD activity for about 20s after which the system has locked up.
Expected Results: Some form of I/O error from md5sum indicating a bad CD.
Please retry with todays 1398 kernel update, as there were a number of IDE layer
fixes including one involving CDs.
Retested with 2.6.12-1.1398_FC4.
I now get "md5sum: /dev/cdrom: Input/output error" as expected and no crash.