Messages in this thread | | | Subject | Re: [PATCH] perf/core: don't WARN for impossible rb sizes | From | "Jin, Yao" <> | Date | Wed, 13 Feb 2019 09:40:05 +0800 |
| |
On 2/12/2019 9:07 PM, Peter Zijlstra wrote: > On Tue, Feb 12, 2019 at 10:42:38AM +0800, Jin, Yao wrote: >>> diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c >>> index 4a9937076331..309ef5a64af5 100644 >>> --- a/kernel/events/ring_buffer.c >>> +++ b/kernel/events/ring_buffer.c >>> @@ -734,6 +734,9 @@ struct ring_buffer *rb_alloc(int nr_pages, long watermark, int cpu, int flags) >>> size = sizeof(struct ring_buffer); >>> size += nr_pages * sizeof(void *); >>> + if (order_base_2(size) >= MAX_ORDER) >>> + goto fail; >>> + >>> rb = kzalloc(size, GFP_KERNEL); > > Yes, Boris also send the entire morning bisecting this. > > The problem is that @size is in bytes and MAX_ORDER is in pages. > > That should be: > > if (order_base_2(size) >= PAGE_SHIFT+MAX_ORDER) > >
Thanks Peter! This fix works!
Thanks Jin Yao
| |