On Wed, 13 Dec 2017 15:05:55 +0100 Sebastian Andrzej Siewior <bige...@linutronix.de> wrote:
> Under certain circumstances we could leak elements which were moved to > the local "to_free" list. The damage is limited since I can't find any > users here. > > Cc: stable...@vger.kernel.org > Signed-off-by: Sebastian Andrzej Siewior <bige...@linutronix.de> > --- > Jesper: There are no users of kmem_cache_alloc_bulk() and kfree_bulk(). > Only kmem_cache_free_bulk() is used since it was introduced. Do you > think that it would make sense to remove those? I would like to keep them. Rao Shoaib (Cc'ed) is/was working on a patchset for RCU-bulk-free that used the kfree_bulk() API. I plan to use kmem_cache_alloc_bulk() in the bpf-map "cpumap", for bulk allocating SKBs during dequeue of XDP frames. (My original bulk alloc SKBs use-case during NAPI/softirq was never merged). > mm/slub.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/mm/slub.c b/mm/slub.c > index ffd2fa0f415e..9053e929ce9d 100644 > --- a/mm/slub.c > +++ b/mm/slub.c > @@ -3240,6 +3240,7 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t > flags, size_t size, > return i; > error: > local_irq_enable(); > + free_delayed(&to_free); > slab_post_alloc_hook(s, flags, i, p); > __kmem_cache_free_bulk(s, i, p); > return 0; I've not seen free_delayed() before... and my cscope cannot find it... -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer
