serial core expects the spinlock to be initialized by the controller driver for serial console, this patch makes sure the spinlock is initialized, fixing the below issue:
[ 0.865928] BUG: spinlock bad magic on CPU#0, swapper/0/1 [ 0.865945] lock: sci_ports+0x0/0x4c80, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0 [ 0.865955] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc1+ #112 [ 0.865961] Hardware name: HopeRun HiHope RZ/G2H with sub board (DT) [ 0.865968] Call trace: [ 0.865979] dump_backtrace+0x0/0x1d8 [ 0.865985] show_stack+0x14/0x20 [ 0.865996] dump_stack+0xe8/0x130 [ 0.866006] spin_dump+0x6c/0x88 [ 0.866012] do_raw_spin_lock+0xb0/0xf8 [ 0.866023] _raw_spin_lock_irqsave+0x80/0xa0 [ 0.866032] uart_add_one_port+0x3a4/0x4e0 [ 0.866039] sci_probe+0x504/0x7c8 [ 0.866048] platform_drv_probe+0x50/0xa0 [ 0.866059] really_probe+0xdc/0x330 [ 0.866066] driver_probe_device+0x58/0xb8 [ 0.866072] device_driver_attach+0x6c/0x90 [ 0.866078] __driver_attach+0x88/0xd0 [ 0.866085] bus_for_each_dev+0x74/0xc8 [ 0.866091] driver_attach+0x20/0x28 [ 0.866098] bus_add_driver+0x14c/0x1f8 [ 0.866104] driver_register+0x60/0x110 [ 0.866109] __platform_driver_register+0x40/0x48 [ 0.866119] sci_init+0x2c/0x34 [ 0.866127] do_one_initcall+0x88/0x428 [ 0.866137] kernel_init_freeable+0x2c0/0x328 [ 0.866143] kernel_init+0x10/0x108 [ 0.866150] ret_from_fork+0x10/0x18 Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad...@bp.renesas.com> Reviewed-by: Biju Das <biju.das...@bp.renesas.com> --- drivers/tty/serial/sh-sci.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index ae8463a..2d3169f 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -3298,6 +3298,9 @@ static int sci_probe_single(struct platform_device *dev, sciport->port.flags |= UPF_HARD_FLOW; } + if (sci_uart_driver.cons->index == sciport->port.line) + spin_lock_init(&sciport->port.lock); + ret = uart_add_one_port(&sci_uart_driver, &sciport->port); if (ret) { sci_cleanup_single(sciport); -- 2.7.4