On Wednesday, 21 March 2007 23:21, Pavel Machek wrote: > Hi! > > > Starting with 2.6.21-rc1 suspend to ram and disk doesn't work anymore on my > > system. > > > > I did a git-bisect and found that those commits break it: > > > > e3c7db621bed4afb8e231cb005057f2feb5db557 - [PATCH] [PATCH] PM: Change code > > ordering in main.c > > ed746e3b18f4df18afa3763155972c5835f284c5 - [PATCH] [PATCH] swsusp: Change > > code ordering in disk.c > > 259130526c267550bc365d3015917d90667732f1 - [PATCH] [PATCH] swsusp: Change > > code ordering in user.c > > > > (Yep, it was in my "to analyze" queue). > > > I already reported about it, but now i know the reason why suspend breaks. > > > > The problem is that both cpu_up/cpu_down were allowed to sleep until now, > > and it did work because those functions could be called only in process > > context > > (the one that writes to /sys/devices/system/cpu/cpu*/online) or idle > > thread that does smp_init()). > > > > But now they are called _after_ all tasks were suspended, so if cpu_down > > tries for example to take a lock > > that is taken by different process, it can't since the different proccess > > is frozen and can't release the lock. > > > > Thanks for detailed explanation. > > ...but, on my machine suspend works ok in -rc4. I'm not seeing this. > > ...by design, "frozen" tasks must not hold any locks. If frozen task > holds a lock, that's a bug. > > > Or, it is also possible to revert this change. > > Are you using xfs?
Well, this is the only case that can trigger it. There are no other freezable workqueues. Greetings, Rafael - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
