rxrpc_new_incoming_peer() can't use spin_lock_bh() whilst its caller has
interrupts disabled.
WARNING: CPU: 0 PID: 1550 at kernel/softirq.c:369 __local_bh_enable_ip+0x46/0xd0
...
Call Trace:
rxrpc_alloc_incoming_call+0x1b0/0x400
rxrpc_new_incoming_call+0x1dd/0x5e0
rxrpc_input_packet+0x84a/0x920
rxrpc_io_thread+0x40d/0xb40
kthread+0x2ec/0x300
ret_from_fork+0x24/0x40
ret_from_fork_asm+0x1a/0x30
</TASK>
irq event stamp: 1811
hardirqs last enabled at (1809): _raw_spin_unlock_irq+0x24/0x50
hardirqs last disabled at (1810): _raw_read_lock_irq+0x17/0x70
softirqs last enabled at (1182): handle_softirqs+0x3ee/0x430
softirqs last disabled at (1811): rxrpc_new_incoming_peer+0x56/0x120
Fix this by using a plain spin_lock() instead. IRQs are held, so softirqs
can't happen.
Fixes: a2ea9a9072 ("rxrpc: Use irq-disabling spinlocks between app and I/O thread")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
Link: https://patch.msgid.link/20250218192250.296870-4-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
71f5409176