Hi,
On Tue, Feb 1, 2022 at 12:28 AM Daniel Borkmann <daniel@xxxxxxxxxxxxx> wrote:
>
> On 1/31/22 12:46 PM, Hou Tao wrote:
> > Now the ringbuf area in /proc/vmallocinfo is showed as vmalloc,
> > but VM_ALLOC is only used for vmalloc(), and for the ringbuf area
> > it is created by mapping allocated pages, so use VM_MAP instead.
> >
> > After the change, ringbuf info in /proc/vmallocinfo will changed from:
> > [start]-[end] 24576 ringbuf_map_alloc+0x171/0x290 vmalloc user
> > to
> > [start]-[end] 24576 ringbuf_map_alloc+0x171/0x290 vmap user
>
> Could you elaborate in the commit msg if this also has some other internal
> effect aside from the /proc/vmallocinfo listing? Thanks!
>
For now, the VM_MAP flag only affects the output in /proc/vmallocinfo.
Thanks,
Tao
> > Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx>
> > ---
> > kernel/bpf/ringbuf.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/kernel/bpf/ringbuf.c b/kernel/bpf/ringbuf.c
> > index 638d7fd7b375..710ba9de12ce 100644
> > --- a/kernel/bpf/ringbuf.c
> > +++ b/kernel/bpf/ringbuf.c
> > @@ -104,7 +104,7 @@ static struct bpf_ringbuf *bpf_ringbuf_area_alloc(size_t data_sz, int numa_node)
> > }
> >
> > rb = vmap(pages, nr_meta_pages + 2 * nr_data_pages,
> > - VM_ALLOC | VM_USERMAP, PAGE_KERNEL);
> > + VM_MAP | VM_USERMAP, PAGE_KERNEL);
> > if (rb) {
> > kmemleak_not_leak(pages);
> > rb->pages = pages;
> >
>
