Red Hat Bugzilla – Bug 566581
blkid appears to break CD-R burning
Last modified: 2010-04-19 06:22:21 EDT
Running blkid on a CD/DVD recorder while burning a disc kills the burn.
Unfortunately udev runs blkid automatically when burning starts, this effectively makes it impossible to burn CD or DVDs.
+++ This bug was initially created as a clone of Bug #566535 +++
Description of problem:
By default, up-to-date F12 x86_64 installation can't burn on SATA burner. A new burner was purchased and same result.
Version-Release number of selected component (if applicable):
Also, killing udevd fixes the problem 100%
Steps to Reproduce:
1. Attempt to burn CD with brasero (may be sata specific)
from running wodim by hand:
Sending CUE sheet...
SAO startsec: -11607
Errno: 5 (Input/output error), write_g1 scsi sendcmd: no error
CDB: 2A 00 FF FF FB 49 00 02 8A 00
status: 0x2 (CHECK CONDITION)
Sense Bytes: 70 00 05 00 00 00 00 0A 2A 00 00 80 30 05 00 00
Sense Key: 0x5 Illegal Request, Segment 0
Sense Code: 0x30 Qual 0x05 (cannot write medium - incompatible format) Fru 0x0
Sense flags: Blk 0 (not valid)
cmd finished after 0.006s timeout 200s
write CD-Text data: error after 998400 bytes
wodim: Could not write Lead-in.
Writing time: 18.527s
wodim: fifo had 255 puts and 0 gets.
wodim: fifo was 0 times empty and 0 times full, min fill was 100%.
no sense errors
* `sudo killall udevd` and then repeating the command will succeed.
* commenting out all lines in 70-persistent-cd.rules
My theory is that udev is acting on the kernel uevent that happens when brasero starts to write, and somehow impacts the system
--- Additional comment from firstname.lastname@example.org on 2010-02-18 13:49:25 EST ---
Created an attachment (id=394964)
Run with udevd killed
--- Additional comment from email@example.com on 2010-02-18 14:00:13 EST ---
Created an attachment (id=394968)
commented log from udevadm monitor --udev --property --kernel
--- Additional comment from firstname.lastname@example.org on 2010-02-18 14:03:51 EST ---
Looking at udev rules I do see that everything gets passed to hal.
However, the issue still occurs after `service haldaemon stop`
--- Additional comment from email@example.com on 2010-02-18 14:12:54 EST ---
it has to do with 60-cdrom_id.rules.
It seems that cdrom_id runs against the cd burner at the point where burning starts in the udev log I attached.
I can burn CDs / DVDs by creating an empty file with this name in /etc/udev/rules.d
--- Additional comment from firstname.lastname@example.org on 2010-02-18 15:56:01 EST ---
digging around with systemtap it seems there are several things that open /dev/sr0 while wodim is burning.
I then disabled 60-persistent-storage.rules and ran them during burns to see what was causing the problem.
Things that come from udev which read from sr0 that don't honor O_EXCL:
blkid - kills burns instantly
devkit-disks-part-id - kills burns instantly
cdrom_id - doesn't kill burns
scsi_id - doesn't kill burns
hald-addon-storage opens sr0 every second or so but uses O_EXCL and thus doesn't interfere.
with recent udev versions, cdrom_id uses O_EXCL, and blkid will not run, if cdrom_id was blocked and does not report ID_CDROM_MEDIA=1
sry. of course: http://admin.fedoraproject.org/updates/udev-145-20.fc12