Re: Patch "percpu: fix a memory leak in pcpu_extend_area_map()" has been added to the 2.6.35-stable tree

[Greg KH <gregkh@suse.de>]

On Thu, Sep 16, 2010 at 11:39:02PM +0200, Stefan Lippers-Hollmann wrote:
> Hi
> 
> On Thursday 16 September 2010, gregkh@suse.de wrote:
> > This is a note to let you know that I've just added the patch titled
> >     percpu: fix a memory leak in pcpu_extend_area_map()
> > to the 2.6.35-stable tree which can be found at:
> >     http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> [...]
> > From a002d148426f40bc2b7dc066982eb177cdebeaaa Mon Sep 17 00:00:00 2001
> > From: Huang Shijie <shijie8@gmail.com>
> > Date: Sun, 8 Aug 2010 14:39:07 +0200
> > Subject: percpu: fix a memory leak in pcpu_extend_area_map()
> > 
> > From: Huang Shijie <shijie8@gmail.com>
> > 
> > commit a002d148426f40bc2b7dc066982eb177cdebeaaa upstream.
> > 
> > The original code did not free the old map.  This patch fixes it.
> > 
> > tj: use @old as memcpy source instead of @chunk->map, and indentation
> >     and description update
> 
> This patch, as part of the current -stable queue-2.6.35, breaks booting for
> me on nforce4/ AMD64 X2. Unfortunately it fails even before the serial 
> console is initialized and the only messages shown on screen are:
> 
> Decompressing Linux... Parsing ELF... done.
> Booting kernel.
> 
> [...]
> > --- a/mm/percpu.c
> > +++ b/mm/percpu.c
> > @@ -390,7 +390,9 @@ static int pcpu_extend_area_map(struct p
> >  		goto out_unlock;
> >  
> >  	old_size = chunk->map_alloc * sizeof(chunk->map[0]);
> > -	memcpy(new, chunk->map, old_size);
> > +	old = chunk->map;
> > +
> > +	memcpy(new, old, old_size);
> >  
> >  	/*
> >  	 * map_alloc < PCPU_DFL_MAP_ALLOC indicates that the chunk is
> 
> Reverting just this patch from the current queue-2.6.35 fixes the issue for
> me; gzipped kernel config (amd64) attached.

Does Linus's tree also cause the same problems for you?

thanks,

greg k-h