Re: [linux-pm] Re: [PATCH] Remove process freezer from suspend to RAM pathway

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Am Donnerstag, 5. Juli 2007 schrieb Miklos Szeredi:
> > > > I have discussed the benefits elsewhere.  As for the deadlocks -- do 
> > > > you still observe them if you use the version of the freezer which 
> > > > doesn't freeze kernel threads?
> > > 
> > > In general the only way to guarantee there are no deadlocks is to
> > > construct the graph of dependencies between tasks.  Those dependencies
> > > are not in practice observable from outside the tasks, so it is
> > > virtually impossible to construct the graph.
> > 
> > In which way can user space tasks depend on each other in a way that
> > allows a them members of that cycle to be in uninterruptible sleep?
> 
>  - process A calls rename() on a fuse fs
>  - process B, the fuse server, starts to process the rename request
>  - process B is frozen before it can reply
> 
> Now process A is unfreezable.  We cannot make rename() restartable,
> hence it cannot be interruptible.

Then this is a problem specific to fuse. You should teach fuse to block
suspension while such operations are being performed.

	Regards
		Oliver

-
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/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux