On Fri, 11 Jul 2008, Eric W. Biederman wrote: > > Forcing the second set of requests to filter through an extra software > > layer is a clumsy way of accomplishing this. There ought to be a > > better approach. > > The point was something different. The reasons we can not store the > state of the system with the hardware devices logically hot unplugged > (and thus reuse all of the find device hotplug methods) is because > things like the filesystem layer don't know how to cope with their > block devices going away an coming back. This is not how the procedure works. During hibernation, block devices are not logically hot-unplugged. (If they were then they couldn't be used for writing the memory image.) Instead, they are quiesced or suspended and their input queues are plugged. > That is the problem inserting an virtual software device in the middle > can solve. If that works should there be a better way? Certainly but > to prove it out starting with a block device wrapper is a trivial way to > go. This sounds like a solution to a non-existent problem. Alan Stern
