Latest working kernel version: 2.6.24-1-686 (distro kernel) Earliest failing kernel version: 2.6.25-1-686 (distro kernel) Distribution: Debian Unstable/Sid Hardware Environment: Dell Latitude D420 Laptop (Core Duo, 1.5GB RAM) Software Environment: Debian Unstable/Sid Problem Description: Since Debian updated to kernel version 2.6.25 I have been experiencing long (5s, 10s, 30s) delays in the boot process. For a long time I kept booting the 2.6.24 distro kernel to avoid the problem. The problem continued with Debian's 2.6.26 distro kernel, so I decided to try upstream 2.6.28 kernel as well. This has the same problem. Steps to reproduce: Boot any kernel >= 2.6.25 on a (my?) Dell Latitude D420 laptop e.g. there seems to be a 4 second delay where nothing else happens before the usb-mass storage scan completes: [ 4.004967] hub 2-2.3:1.0: USB hub found [ 4.006877] hub 2-2.3:1.0: 3 ports detected [ 4.012076] usb 2-2.3: New USB device found, idVendor=0b97, idProduct=7761 [ 4.012153] usb 2-2.3: New USB device strings: Mfr=0, Product=0, SerialNumber=0 [ 4.285965] usb 2-2.3.2: new full speed USB device using uhci_hcd and address 4 [ 4.401140] usb 2-2.3.2: configuration #1 chosen from 1 choice [ 4.404341] usb 2-2.3.2: New USB device found, idVendor=0b97, idProduct=7762 [ 4.404423] usb 2-2.3.2: New USB device strings: Mfr=1, Product=2, SerialNumber=0 [ 4.404515] usb 2-2.3.2: Product: O2Micro CCID SC Reader [ 4.404584] usb 2-2.3.2: Manufacturer: O2 [ 8.308340] usb-storage: device scan complete Then, shortly after there is huge (38s?) delay before filesystems get mounted. [ 8.311116] scsi 2:0:0:0: CD-ROM HL-DT-ST DVD+-RW GWA4083N B105 PQ: 0 ANSI: 0 [ 8.324642] sr0: scsi3-mmc drive: 24x/24x writer cd/rw xa/form2 cdda tray [ 8.324721] Uniform CD-ROM driver Revision: 3.20 [ 8.324972] sr 2:0:0:0: Attached scsi CD-ROM sr0 [ 8.325125] sr 2:0:0:0: Attached scsi generic sg1 type 5 [ 46.153440] PM: Starting manual resume from disk [ 46.189837] kjournald starting. Commit interval 5 seconds [ 46.189927] EXT3-fs: mounted filesystem with ordered data mode. [ 49.372377] udevd version 125 started I'll attach the full syslog from a boot of 2.6.28, with CONFIG_USB_STORAGE_DEBUG enabled and me hitting alt-sysrq-t during the delay periods. Hopefully that contains some clue as to what everything is waiting on.
Created attachment 19503 [details] Kernel config used for 2.6.28
Created attachment 19504 [details] syslog from boot of 2.6.28 Here is the syslog extract from a full boot of 2.6.28. Note the delays at 4.404584s and 8.349727s. I hit alt-sysrq-t during both these delays, hoping that something useful would show up. There is another ~30s delay at 52.761617s, but I didn't get the sysrq output for that one this time.
hm, init is waiting for some process, but which? Perhaps something udev-related. That sysrq output is useful.
Some recent update to Debian userspace seems to have fixed this. Unfortunately I can't point to exactly what, except to say boot times are back to normal now with a kernel.org 2.6.28 or 2.6.29 kernel and current Debian (Sid/unstable) userspace.