On Fri, 3 Dec 2010 00:40:36 +0100 "Rafael J. Wysocki" <rjw@xxxxxxx> wrote: > From: Rafael J. Wysocki <rjw@xxxxxxx> > > There is a problem that swap pages allocated before the creation of > a hibernation image can be released and used for storing the contents > of different memory pages while the image is being saved. Since the > kernel stored in the image doesn't know of that, it causes memory > corruption to occur after resume from hibernation, especially on > systems with relatively small RAM that need to swap often. > > This issue can be addressed by keeping the GFP_IOFS bits clear > in gfp_allowed_mask during the entire hibernation, including the > saving of the image, until the system is finally turned off or > the hibernation is aborted. Unfortunately, for this purpose > it's necessary to rework the way in which the hibernate and > suspend code manipulates gfp_allowed_mask. > > This change is based on an earlier patch from Hugh Dickins. > > Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx> > Reported-by: Ondrej Zary <linux@xxxxxxxxxxxxxxxxxxxx> > Acked-by: Hugh Dickins <hughd@xxxxxxxxxx> > --- > > Hi, > > This patch is a fix for a regression and nasty memory corruption, so I'd like > to push it to Linus for 2.6.37 if there are no objections. > It looks OK to me for 2.6.37 but for 2.6.38 please let's make everything here a 100% no-op for CONFIG_PM_SLEEP=n builds. Specifically the slight overhead in __alloc_pages_nodemask. Because given the global nature of saved_gfp_mask and the unlocked way in which it is accessed, this facility won't be at all useful for anything other than suspend. _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
