Subject: Re: [PATCH SLUB 1/2] duplicate the cache name in saved_alias list

From: Li Zhong <[email-masked]>
Date: Tue, 26 Jun 2012 10:49:24 +0800

On Mon, 2012-06-25 at 18:54 +0800, Wanlong Gao wrote:
> On 06/25/2012 05:53 PM, Li Zhong wrote:
> > SLUB duplicates the cache name in kmem_cache_create(). However if the
> > cache could be merged to others during early booting, the name pointer
> > is saved in saved_alias list, and the string needs to be kept valid
> > before slab_sysfs_init() is called. 
> > 
> > This patch tries to duplicate the cache name in saved_alias list, so
> > that the cache name could be safely kfreed after calling
> > kmem_cache_create(), if that name is kmalloced. 
> > 
> > Signed-off-by: Li Zhong <[email-masked]>
> > ---
> >  mm/slub.c |    6 ++++++
> >  1 files changed, 6 insertions(+), 0 deletions(-)
> > 
> > diff --git a/mm/slub.c b/mm/slub.c
> > index 8c691fa..3dc8ed5 100644
> > --- a/mm/slub.c
> > +++ b/mm/slub.c
> > @@ -5373,6 +5373,11 @@ static int sysfs_slab_alias(struct kmem_cache *s,
> > const char *name)
> >  
> >  	al->s = s;
> >  	al->name = name;
> > +	al->name = kstrdup(name, GFP_KERNEL);
> 
> dup assigned the al->name ?
> 

Ah, yes, there should be a '-' before the line al->name = name;

Thank you, I will update it. 

> Thanks,
> Wanlong Gao
> 
> > +	if (!al->name) {
> > +		kfree(al);
> > +		return -ENOMEM;
> > +	}
> >  	al->next = alias_list;
> >  	alias_list = al;
> >  	return 0;
> > @@ -5409,6 +5414,7 @@ static int __init slab_sysfs_init(void)
> >  		if (err)
> >  			printk(KERN_ERR "SLUB: Unable to add boot slab alias"
> >  					" %s to sysfs\n", s->name);
> > +		kfree(al->name);
> >  		kfree(al);
> >  	}
> >  
> > 
> 
> 
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