LinuxCon: A tale of two bootcharts
Posted Aug 27, 2010 20:13 UTC (Fri) by BenHutchings
In reply to: LinuxCon: A tale of two bootcharts
Parent article: LinuxCon: A tale of two bootcharts
It strikes me, however, that the basic problem *here* is finding out what hardware is present and not present.
I think you're confused about how hardware probing is done. Back in the 90s PCs would have a load of ISA devices that each had to be probed in their own way. Today almost every device is described by ACPI tables or the standard PCI or USB configuration mechanisms. The kernel uses these to find which devices are present and only invokes the drivers associated with them. It also sends events out to udev, which loads modules if needed. The 'probing' I refer to involves drivers checking which variant is present and then initialising it appropriately; drivers that you don't need will never be invoked. (There are exceptions, e.g. 8139cp and 8139too handle different devices with overlapping sets of device IDs. Normally they will both be loaded and may both probe the same device.)
This could be mitigated by means of a table of "known to be present" hardware information supplied to a bulk-loaded module set (something along the lines of putting all the .ko's into a single .ko with tables specifying that it's a bulk module and where everybody's at in it, as outlined above.)
That might be worth a try.
to post comments)