On Fri, 4 Jun 2010, Maxim Levitsky wrote: > On Fri, 2010-06-04 at 10:59 -0400, Alan Stern wrote: > > On Fri, 4 Jun 2010, Maxim Levitsky wrote: > > > > > On Thu, 2010-03-04 at 14:53 +0100, Pavel Machek wrote: > > > > Hi! > > > > > > > > > > journalling assumptions broken: commit block is there, but previous > > > > > > blocks are not intact. Data loss. > > > > > > > > > > > > ...and that was the first I could think about. Lets not do > > > > > > this. Barriers were invented for a reason. > > > > > > > > > > Very well. Then we still need a solution to the original problem: > > > > > Devices sometimes need to be unregistered during resume, but > > > > > del_gendisk() blocks on the writeback thread, which is frozen until > > > > > after the resume finishes. How do you suggest this be fixed? > > > > > > > > Avoid unregistering device during resume. Instead, return errors until > > > > resume is done and you can call del_gendisk? > > > > > > This won't help ether. The same driver needs to unregister perfectly > > > working device on suspend, because the user might replace the card > > > during suspend and fool the os. > > > There is a setting, CONFIG_MMC_UNSAFE_RESUME and I use it, but it isn't > > > default. > > > > People have generally agreed that the best answer is to have > > del_gendisk always thaw the writeback thread. > Now the question is how to do that? :-) Here's a start: http://marc.info/?l=linux-kernel&m=127378922620074&w=2 It's not quite right, because it needs to make the writeback thread unfreezable before thawing it. Alan Stern _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
