Ubuntu
lvm2 package

  1. Bug #802626
  2. Comment #5

Comment 5 for bug 802626

Revision history for this message
Eduard Hasenleithner (eduard-hasenleithner) wrote : Re: boot hangs at initrd

I managed to obtain a logfile from the lvm command when it hangs:

libdm-deptree.c:941 Resuming phenom-data2 (253:0)
libdm-common.c:1153 Udev cookie 0xd4d0511 (semid 0) created
libdm-common.c:1166 Udev cookie 0xd4d0511 (semid 0) incremented
libdm-common.c:1054 Udev cookie 0xd4d0511 (semid 0) incremented
libdm-common.c:1226 Udev cookie 0xd4d0511 (semid 0) assigned to dm_task type 5 with flags 0x0
ioctl/libdm-iface.c:1821 dm resume (253:0) NF [16384]
libdm-common.c:828 phenom-data2: Stacking NODE_READ_AHEAD 256 (flags=1)
libdm-common.c:1081 Udev cookie 0xd4d0511 (semid 0) decremented
libdm-common.c:1276 Udev cookie 0xd4d0511 (semid 0): Waiting for zero

Obviously, lvm waits for udev to decrement the device-mapper task semaphore. A strange observation is that when looking at "ps ax" the PID(s) of udevd (437,829,839) suggest that udevd was started after the lvm tool (pid 355). Maybe there is a small time window when udevd is not able to perform the semaphore decrementation.