Hi Greg, > -----Original Message----- > From: gregkh@xxxxxxxxxxxxxxxxxxx <gregkh@xxxxxxxxxxxxxxxxxxx> > Sent: 03 July 2020 09:41 > To: Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>; Biju Das <biju.das.jz@xxxxxxxxxxxxxx>; > gregkh@xxxxxxxxxxxxxxxxxxx; stable@xxxxxxxxxxxxxxx > Subject: patch "serial: sh-sci: Initialize spinlock for uart console" added to tty-linus > > > This is a note to let you know that I've just added the patch titled > > serial: sh-sci: Initialize spinlock for uart console > > to my tty git tree which can be found at > git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git > in the tty-linus branch. > > The patch will show up in the next release of the linux-next tree > (usually sometime within the next 24 hours during the week.) > > The patch will hopefully also be merged in Linus's tree for the > next -rc kernel release. > > If you have any questions about this process, please let me know. > It looks like it's a regression in serial_core.c [1] as Geert pointed out [2]. Please drop this patch until we come to a conclusion. [1] https://www.spinics.net/lists/linux-serial/msg37119.html [2] https://patchwork.kernel.org/patch/11636731/ Cheers, --Prabhakar > > From f38278e9b810b06aff2981d505267be984423ba3 Mon Sep 17 00:00:00 2001 > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx> > Date: Wed, 1 Jul 2020 16:41:40 +0100 > Subject: 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: <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@xxxxxxxxxxxxxx> > Reviewed-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx> > Fixes: a3cb39d258ef ("serial: core: Allow detach and attach serial device for console") > Cc: stable <stable@xxxxxxxxxxxxxxx> > Link: https://lore.kernel.org/r/1593618100-2151-1-git-send-email-prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > --- > 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 e1179e74a2b8..204bb68ce3ca 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); > -- > 2.27.0 > Renesas Electronics Europe GmbH, Geschaeftsfuehrer/President: Carsten Jauch, Sitz der Gesellschaft/Registered office: Duesseldorf, Arcadiastrasse 10, 40472 Duesseldorf, Germany, Handelsregister/Commercial Register: Duesseldorf, HRB 3708 USt-IDNr./Tax identification no.: DE 119353406 WEEE-Reg.-Nr./WEEE reg. no.: DE 14978647
