From: Lad Prabhakar Date: Wed, 1 Jul 2020 15:41:40 +0000 (+0100) Subject: serial: sh-sci: Initialize spinlock for uart console X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=f38278e9b810b06aff2981d505267be984423ba3;p=linux.git serial: sh-sci: Initialize spinlock for uart console 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: /-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 Reviewed-by: Biju Das Fixes: a3cb39d258ef ("serial: core: Allow detach and attach serial device for console") Cc: stable Link: https://lore.kernel.org/r/1593618100-2151-1-git-send-email-prabhakar.mahadev-lad.rj@bp.renesas.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index e1179e74a2b89..204bb68ce3ca9 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -3301,6 +3301,9 @@ 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);