FAILED: Patch "io_uring/zcrx: fix post open error handling" failed to apply to 6.18-stable tree

FAILED: Patch "io_uring/zcrx: fix post open error handling" failed to apply to 6.18-stable tree

[Sasha Levin]

The patch below does not apply to the 6.18-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

Thanks,
Sasha

------------------ original commit in Linus's tree ------------------

From 5d540e4508950c674d6feef1d95463d039bbf4f5 Mon Sep 17 00:00:00 2001
From: Pavel Begunkov <asml.silence@gmail.com>
Date: Sat, 14 Feb 2026 22:20:47 +0000
Subject: [PATCH] io_uring/zcrx: fix post open error handling

Closing a queue doesn't guarantee that all associated page pools are
terminated right away, let the refcounting do the work instead of
releasing the zcrx ctx directly.

Cc: stable@vger.kernel.org
Fixes: e0793de24a9f6 ("io_uring/zcrx: set pp memory provider for an rx queue")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 io_uring/zcrx.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/io_uring/zcrx.c b/io_uring/zcrx.c
index 006e1bfefa5f2..b24d1da2e1ca4 100644
--- a/io_uring/zcrx.c
+++ b/io_uring/zcrx.c
@@ -515,9 +515,6 @@ static void io_close_queue(struct io_zcrx_ifq *ifq)
 		.mp_priv = ifq,
 	};
 
-	if (ifq->if_rxq == -1)
-		return;
-
 	scoped_guard(mutex, &ifq->pp_lock) {
 		netdev = ifq->netdev;
 		netdev_tracker = ifq->netdev_tracker;
@@ -525,7 +522,8 @@ static void io_close_queue(struct io_zcrx_ifq *ifq)
 	}
 
 	if (netdev) {
-		net_mp_close_rxq(netdev, ifq->if_rxq, &p);
+		if (ifq->if_rxq != -1)
+			net_mp_close_rxq(netdev, ifq->if_rxq, &p);
 		netdev_put(netdev, &netdev_tracker);
 	}
 	ifq->if_rxq = -1;
@@ -833,13 +831,12 @@ int io_register_zcrx_ifq(struct io_ring_ctx *ctx,
 	}
 	return 0;
 netdev_put_unlock:
-	netdev_put(ifq->netdev, &ifq->netdev_tracker);
 	netdev_unlock(ifq->netdev);
 err:
 	scoped_guard(mutex, &ctx->mmap_lock)
 		xa_erase(&ctx->zcrx_ctxs, id);
 ifq_free:
-	io_zcrx_ifq_free(ifq);
+	zcrx_unregister(ifq);
 	return ret;
 }
 
-- 
2.51.0

Re: FAILED: Patch "io_uring/zcrx: fix post open error handling" failed to apply to 6.18-stable tree

[Jens Axboe]

On 2/28/26 6:17 PM, Sasha Levin wrote:
> The patch below does not apply to the 6.18-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@vger.kernel.org>.

Looks like this has dependencies on parts of this:

https://lore.kernel.org/io-uring/cover.1763029704.git.asml.silence@gmail.com/

series. But seems easier to just do a variant for the 6.18 base,
I'll leave that to Pavel.

-- 
Jens Axboe