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* [PATCH] serial: sh-sci: Initialize spinlock for uart console
@ 2020-07-01 15:41 Lad Prabhakar
  2020-07-01 16:40 ` Greg Kroah-Hartman
  2020-07-01 17:17 ` Geert Uytterhoeven
  0 siblings, 2 replies; 11+ messages in thread
From: Lad Prabhakar @ 2020-07-01 15:41 UTC (permalink / raw)
  To: Geert Uytterhoeven, Greg Kroah-Hartman, Jiri Slaby
  Cc: linux-renesas-soc, linux-serial, linux-kernel, Prabhakar,
	Biju Das, Lad Prabhakar

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.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@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


^ permalink raw reply related	[flat|nested] 11+ messages in thread
end of thread, other threads:[~2020-07-02 18:32 UTC | newest]

Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-07-01 15:41 [PATCH] serial: sh-sci: Initialize spinlock for uart console Lad Prabhakar
2020-07-01 16:40 ` Greg Kroah-Hartman
2020-07-01 17:17 ` Geert Uytterhoeven
2020-07-01 17:28   ` Lad, Prabhakar
2020-07-02  9:23     ` Geert Uytterhoeven
2020-07-02 10:49       ` Lad, Prabhakar
2020-07-02 11:42         ` Lad, Prabhakar
2020-07-02 12:52           ` Geert Uytterhoeven
2020-07-02 14:05             ` Lad, Prabhakar
2020-07-02 14:39               ` Geert Uytterhoeven
2020-07-02 18:32                 ` Lad, Prabhakar

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