2008/3/6, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>: > On Thu, 6 Mar 2008, Pavel Machek wrote: > > > On Tue 2008-03-04 16:00:51, Alan Stern wrote: > > > On Tue, 4 Mar 2008, David Brownell wrote: > > > > > > > > What's wrong with a superfluous probe at resume time, besides the waste > > > > > of a few milliseconds? > > > > > > > > I'm more concerned with the undesirable removal of devices at suspend > > > > time ... ones with mounted filesystems etc. > > > > > > On that we can agree. The removal is done if the host doesn't define a > > > resume method. There doesn't seem to be any point to that, given that > > > the probing during resume will determine whether a card has in fact > > > been removed. > > > > Hmm, if the driver is sleeping too deeply, user might have removed the > > card and put in different one, without driver noticing. That would be > > _bad_. > > > Ironically, the very same problem now exists with the USB mass-storage > driver. I don't see any way for the driver itself to solve it, > especially during a hibernation (which can be a _very_ deep sleep). > > One thing that could be done is for filesystems to verify, after a > system sleep, that their superblocks haven't changed. There could > still be issues with non-mounted partitions, if they have live entries > in the block cache, but it would be an improvement. > > Do you know the right people to mention this to? Anybody in filesystem > development interested in suspend/hibernation issues? IMHO the way would be to try to unmount fs if it's possible - if not - user should be notified on suspend/hibernation that he must preserve media in its place after resume and it should be checked and user should be notified if different devices/fs were find... Zdenek _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
