[PATCH net v12 08/15] rxrpc: Fix double IRQ enablement

[David Howells <dhowells@redhat.com>]

rxrpc_notify_socket() explicitly disables and then re-enables IRQs, but one
of its call chains (rxrpc_input_queue_data() -> rxrpc_end_rx_phase() ->
rxrpc_call_completed() -> rxrpc_set_call_completion()) has IRQs disabled
around it.

Fix this by making rxrpc_notify_socket() use irqsave spinlocks.

Fixes: a2ea9a907260 ("rxrpc: Use irq-disabling spinlocks between app and I/O thread")
Link: https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260812110129.979970-6-dhowells@redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
---
 net/rxrpc/recvmsg.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c
index efcba4b2e74f..56fa324d0962 100644
--- a/net/rxrpc/recvmsg.c
+++ b/net/rxrpc/recvmsg.c
@@ -24,6 +24,7 @@ void rxrpc_notify_socket(struct rxrpc_call *call)
 {
 	struct rxrpc_sock *rx;
 	struct sock *sk;
+	unsigned long flags;
 
 	_enter("%d", call->debug_id);
 
@@ -38,16 +39,16 @@ void rxrpc_notify_socket(struct rxrpc_call *call)
 	sk = &rx->sk;
 	if (rx && sk->sk_state < RXRPC_CLOSE) {
 		if (call->notify_rx) {
-			spin_lock_irq(&call->notify_lock);
+			spin_lock_irqsave(&call->notify_lock, flags);
 			call->notify_rx(sk, call, call->user_call_ID);
-			spin_unlock_irq(&call->notify_lock);
+			spin_unlock_irqrestore(&call->notify_lock, flags);
 		} else {
-			spin_lock_irq(&rx->recvmsg_lock);
+			spin_lock_irqsave(&rx->recvmsg_lock, flags);
 			if (list_empty(&call->recvmsg_link)) {
 				rxrpc_get_call(call, rxrpc_call_get_notify_socket);
 				list_add_tail(&call->recvmsg_link, &rx->recvmsg_q);
 			}
-			spin_unlock_irq(&rx->recvmsg_lock);
+			spin_unlock_irqrestore(&rx->recvmsg_lock, flags);
 
 			if (!sock_flag(sk, SOCK_DEAD)) {
 				_debug("call %ps", sk->sk_data_ready);