netdev - [PATCH io_uring for-6.18 13/20] io

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <300922172efe71ba2323f3ce4fb77aa73887fe56.1758030357.git.asml.silence@gmail.com>
Date: Tue, 16 Sep 2025 15:27:56 +0100
From: Pavel Begunkov <asml.silence@...il.com>
To: io-uring@...r.kernel.org
Cc: asml.silence@...il.com,
	axboe@...nel.dk,
	netdev@...r.kernel.org
Subject: [PATCH io_uring for-6.18 13/20] io_uring/zcrx: rename dma lock

In preparation for reusing the lock for other purposes, rename it to
"pp_lock". As before, it can be taken deeper inside the networking stack
by page pool, and so the syscall io_uring must avoid holding it while
doing queue reconfiguration or anything that can result in immediate pp
init/destruction.

Signed-off-by: Pavel Begunkov <asml.silence@...il.com>
---
 io_uring/zcrx.c | 8 ++++----
 io_uring/zcrx.h | 7 ++++++-
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/io_uring/zcrx.c b/io_uring/zcrx.c
index 85832f60d68a..0deb41b74b7c 100644
--- a/io_uring/zcrx.c
+++ b/io_uring/zcrx.c
@@ -253,7 +253,7 @@ static void io_zcrx_unmap_area(struct io_zcrx_ifq *ifq,
 {
 	int i;
 
-	guard(mutex)(&ifq->dma_lock);
+	guard(mutex)(&ifq->pp_lock);
 	if (!area->is_mapped)
 		return;
 	area->is_mapped = false;
@@ -273,7 +273,7 @@ static int io_zcrx_map_area(struct io_zcrx_ifq *ifq, struct io_zcrx_area *area)
 {
 	int ret;
 
-	guard(mutex)(&ifq->dma_lock);
+	guard(mutex)(&ifq->pp_lock);
 	if (area->is_mapped)
 		return 0;
 
@@ -478,7 +478,7 @@ static struct io_zcrx_ifq *io_zcrx_ifq_alloc(struct io_ring_ctx *ctx)
 	ifq->ctx = ctx;
 	spin_lock_init(&ifq->lock);
 	spin_lock_init(&ifq->rq_lock);
-	mutex_init(&ifq->dma_lock);
+	mutex_init(&ifq->pp_lock);
 	return ifq;
 }
 
@@ -527,7 +527,7 @@ static void io_zcrx_ifq_free(struct io_zcrx_ifq *ifq)
 		put_device(ifq->dev);
 
 	io_free_rbuf_ring(ifq);
-	mutex_destroy(&ifq->dma_lock);
+	mutex_destroy(&ifq->pp_lock);
 	kfree(ifq);
 }
 
diff --git a/io_uring/zcrx.h b/io_uring/zcrx.h
index 7604f1f85ccb..3f89a34e5282 100644
--- a/io_uring/zcrx.h
+++ b/io_uring/zcrx.h
@@ -54,7 +54,12 @@ struct io_zcrx_ifq {
 	struct net_device		*netdev;
 	netdevice_tracker		netdev_tracker;
 	spinlock_t			lock;
-	struct mutex			dma_lock;
+
+	/*
+	 * Page pool and net configuration lock, can be taken deeper in the
+	 * net stack.
+	 */
+	struct mutex			pp_lock;
 	struct io_mapped_region		region;
 };
 
-- 
2.49.0