From: Indan Zupancic <Indan.Zupancic@xxxxxxxxxxxx>
[ Upstream commit 401fb66a355eb0f22096cf26864324f8e63c7d78 ]
If an irq is pending when devm_request_irq() is called, the irq
handler will cause a NULL pointer access because initialisation
is not done yet.
Fixes: 9d7ee0e28da59 ("tty: serial: lpuart: avoid report NULL interrupt")
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Indan Zupancic <Indan.Zupancic@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220505114750.45423-1-Indan.Zupancic@xxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
[5.10 did not have lpuart_global_reset or anything after
uart_add_one_port(), so add the remove call in cleanup manually]
Signed-off-by: Dominique Martinet <dominique.martinet@xxxxxxxxxxxxxxxxx>
---
This was originally intended as a prerequirement to backport the patch
submitted in [1] for 5.10, but even with that part of the patch gone it
makes sense as a fix on its own.
[1] https://lkml.kernel.org/r/20221222114414.1886632-1-linux@xxxxxxxxxxxxxxxxxx
drivers/tty/serial/fsl_lpuart.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 43aca5a2ef0f..223695947b65 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -2586,6 +2586,7 @@ static int lpuart_probe(struct platform_device *pdev)
struct device_node *np = pdev->dev.of_node;
struct lpuart_port *sport;
struct resource *res;
+ irq_handler_t handler;
int ret;
sport = devm_kzalloc(&pdev->dev, sizeof(*sport), GFP_KERNEL);
@@ -2658,17 +2659,12 @@ static int lpuart_probe(struct platform_device *pdev)
if (lpuart_is_32(sport)) {
lpuart_reg.cons = LPUART32_CONSOLE;
- ret = devm_request_irq(&pdev->dev, sport->port.irq, lpuart32_int, 0,
- DRIVER_NAME, sport);
+ handler = lpuart32_int;
} else {
lpuart_reg.cons = LPUART_CONSOLE;
- ret = devm_request_irq(&pdev->dev, sport->port.irq, lpuart_int, 0,
- DRIVER_NAME, sport);
+ handler = lpuart_int;
}
- if (ret)
- goto failed_irq_request;
-
ret = uart_get_rs485_mode(&sport->port);
if (ret)
goto failed_get_rs485;
@@ -2684,11 +2680,17 @@ static int lpuart_probe(struct platform_device *pdev)
if (ret)
goto failed_attach_port;
+ ret = devm_request_irq(&pdev->dev, sport->port.irq, handler, 0,
+ DRIVER_NAME, sport);
+ if (ret)
+ goto failed_irq_request;
+
return 0;
+failed_irq_request:
+ uart_remove_one_port(&lpuart_reg, &sport->port);
failed_get_rs485:
failed_attach_port:
-failed_irq_request:
lpuart_disable_clks(sport);
return ret;
}
--
2.35.1
