[PATCH net v1] net: io_uring/zcrx: call netdev_queue_get_dma_dev() under instance lock
From: David Wei <hidden>
Date: 2025-10-28 21:26:42
Also in:
io-uring
Subsystem:
io_uring, io_uring zcrx, the rest · Maintainers:
Jens Axboe, Pavel Begunkov, Linus Torvalds
netdev ops must be called under instance lock or rtnl_lock, but io_register_zcrx_ifq() isn't doing this for netdev_queue_get_dma_dev(). Fix this by taking the instance lock. Opted to do this by hand instead of netdev_get_by_index_lock(), which is an older helper that doesn't take netdev tracker. Signed-off-by: David Wei <redacted> --- io_uring/zcrx.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/io_uring/zcrx.c b/io_uring/zcrx.c
index a816f5902091..55010c0aa7b9 100644
--- a/io_uring/zcrx.c
+++ b/io_uring/zcrx.c@@ -606,11 +606,13 @@ int io_register_zcrx_ifq(struct io_ring_ctx *ctx, goto err; } + netdev_lock(ifq->netdev); ifq->dev = netdev_queue_get_dma_dev(ifq->netdev, reg.if_rxq); if (!ifq->dev) { ret = -EOPNOTSUPP; - goto err; + goto netdev_unlock; } + netdev_unlock(ifq->netdev); get_device(ifq->dev); ret = io_zcrx_create_area(ifq, &area);
@@ -640,6 +642,8 @@ int io_register_zcrx_ifq(struct io_ring_ctx *ctx, goto err; } return 0; +netdev_unlock: + netdev_unlock(ifq->netdev); err: scoped_guard(mutex, &ctx->mmap_lock) xa_erase(&ctx->zcrx_ctxs, id);
--
2.47.3