Commit 7d4553b6 authored by Jun'ichi Nomura's avatar Jun'ichi Nomura Committed by Daniel Borkmann
Browse files

bpf, devmap: Use GFP_KERNEL for xdp bulk queue allocation 



The devmap bulk queue is allocated with GFP_ATOMIC and the allocation
may fail if there is no available space in existing percpu pool.

Since commit 75ccae62 ("xdp: Move devmap bulk queue into struct net_device")
moved the bulk queue allocation to NETDEV_REGISTER callback, whose context
is allowed to sleep, use GFP_KERNEL instead of GFP_ATOMIC to let percpu
allocator extend the pool when needed and avoid possible failure of netdev
registration.

As the required alignment is natural, we can simply use alloc_percpu().

Fixes: 75ccae62 ("xdp: Move devmap bulk queue into struct net_device")
Signed-off-by: default avatarJun'ichi Nomura <junichi.nomura@nec.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Cc: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210209082451.GA44021@jeru.linux.bs1.fc.nec.co.jp
parent 17d8beda

kernel/bpf/devmap.c

+1 −3
Original line number Diff line number Diff line
@@ -802,9 +802,7 @@ static int dev_map_notification(struct notifier_block *notifier, 
			break;



		/* will be freed in free_netdev() */

		netdev->xdp_bulkq =

			__alloc_percpu_gfp(sizeof(struct xdp_dev_bulk_queue),

					   sizeof(void *), GFP_ATOMIC);

		netdev->xdp_bulkq = alloc_percpu(struct xdp_dev_bulk_queue);

		if (!netdev->xdp_bulkq)

			return NOTIFY_BAD;