I'm trying to understand Linux better, specifically driver registration and such so I'm trying to follow what happens when I insert modules and drivers. From what I thought I understood, kernel events such as module insertion and removal are logged in /var/log/messages, but I'm finding inconsistent results depending on the module. For instance, if I load the usb-storage module, the kernel logs the process to /var/log/messages, as demonstrated below:
[root@lily frank]# modprobe -v usb-storage insmod /lib/modules/2.6.32-573.26.1.el6.i686/kernel/drivers/usb/storage/usb-storage.ko [root@lily dev]# cat /var/log/messages | tail Jun 16 10:03:29 lily kernel: Initializing USB Mass Storage driver... Jun 16 10:03:29 lily kernel: usbcore: registered new interface driver usb-storage Jun 16 10:03:29 lily kernel: USB Mass Storage support registered.
But is when I try the same thing with some other modules, the kernel doesn't log the operation, as demonstrated below with the fcoe driver:
[root@lily dev]# modprobe -v fcoe insmod /lib/modules/2.6.32-573.26.1.el6.i686/kernel/drivers/scsi/scsi_tgt.ko insmod /lib/modules/2.6.32-573.26.1.el6.i686/kernel/drivers/scsi/scsi_transport_fc.ko insmod /lib/modules/2.6.32-573.26.1.el6.i686/kernel/drivers/scsi/libfc/libfc.ko insmod /lib/modules/2.6.32-573.26.1.el6.i686/kernel/drivers/scsi/fcoe/libfcoe.ko insmod /lib/modules/2.6.32-573.26.1.el6.i686/kernel/drivers/scsi/fcoe/fcoe.ko [root@lily dev]# cat /var/log/messages | tail Jun 16 10:03:29 lily kernel: Initializing USB Mass Storage driver... Jun 16 10:03:29 lily kernel: usbcore: registered new interface driver usb-storage Jun 16 10:03:29 lily kernel: USB Mass Storage support registered.
As you can see the kernel hasn't log anything in /var/log/messages since logging the insertion of the usb-storage module. I find it doesn't log the insertion of a lot of modules.
Can somebody tell me the reason for this behavior? Does it have to do with logging levels or something?