[PATCH 5.4 089/111] tty: serial: add missing spin_lock_init for SiFive serial console

From: Greg Kroah-Hartman
Date: Tue May 26 2020 - 15:23:04 EST

From: Sagar Shrikant Kadam <sagar.kadam@xxxxxxxxxx>

commit 17b4efdf4e4867079012a48ca10d965fe9d68822 upstream.

An uninitialised spin lock for sifive serial console raises a bad
magic spin_lock error as reported and discussed here [1].
Initialising the spin lock resolves the issue.

The fix is tested on HiFive Unleashed A00 board with Linux 5.7-rc4
and OpenSBI v0.7

[1] https://lore.kernel.org/linux-riscv/b9fe49483a903f404e7acc15a6efbef756db28ae.camel@xxxxxxx

Fixes: 45c054d0815b ("tty: serial: add driver for the SiFive UART")
Reported-by: Atish Patra <Atish.Patra@xxxxxxx>
Signed-off-by: Sagar Shrikant Kadam <sagar.kadam@xxxxxxxxxx>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>
Acked-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/1589019852-21505-2-git-send-email-sagar.kadam@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

drivers/tty/serial/sifive.c | 1 +
1 file changed, 1 insertion(+)

--- a/drivers/tty/serial/sifive.c
+++ b/drivers/tty/serial/sifive.c
@@ -840,6 +840,7 @@ console_initcall(sifive_console_init);

static void __ssp_add_console_port(struct sifive_serial_port *ssp)
+ spin_lock_init(&ssp->port.lock);
sifive_serial_console_ports[ssp->port.line] = ssp;