Commit bd673d2b authored by Abinash Singh's avatar Abinash Singh Committed by Greg Kroah-Hartman
Browse files

serial: 8250_platform: Reduce stack usage in serial8250_probe_platform() 



 The function serial8250_probe_platform() in 8250_platform.c triggered a
        frame size warning:
drivers/tty/serial/8250/8250_platform.c: In function ‘serial8250_probe_platform.isra’:
drivers/tty/serial/8250/8250_platform.c:201:1: warning: the frame size of 1184 bytes is larger than 1024 bytes [-Wframe-larger-than=]

This patch reduces the stack usage by dynamically allocating the
`uart` structure using kzalloc(), rather than placing it on
the stack. This eliminates the overflow warning and improves kernel
robustness.

Signed-off-by: default avatarAbinash Singh <abinashsinghlalotra@gmail.com>
Reviewed-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20250806215134.4921-3-abinashsinghlalotra@gmail.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent d9b76796

drivers/tty/serial/8250/8250_platform.c

+31 −30
Original line number Diff line number Diff line
@@ -157,43 +157,44 @@ static int serial8250_probe_acpi(struct platform_device *pdev) 


static int serial8250_probe_platform(struct platform_device *dev, struct plat_serial8250_port *p)

{

	struct uart_8250_port uart;

	int ret, i, irqflag = 0;



	memset(&uart, 0, sizeof(uart));

	struct uart_8250_port *uart __free(kfree) = kzalloc(sizeof(*uart), GFP_KERNEL);

	if (!uart)

		return -ENOMEM;



	if (share_irqs)

		irqflag = IRQF_SHARED;



	for (i = 0; p && p->flags != 0; p++, i++) {

		uart.port.iobase	= p->iobase;

		uart.port.membase	= p->membase;

		uart.port.irq		= p->irq;

		uart.port.irqflags	= p->irqflags;

		uart.port.uartclk	= p->uartclk;

		uart.port.regshift	= p->regshift;

		uart.port.iotype	= p->iotype;

		uart.port.flags		= p->flags;

		uart.port.mapbase	= p->mapbase;

		uart.port.mapsize	= p->mapsize;

		uart.port.hub6		= p->hub6;

		uart.port.has_sysrq	= p->has_sysrq;

		uart.port.private_data	= p->private_data;

		uart.port.type		= p->type;

		uart.bugs		= p->bugs;

		uart.port.serial_in	= p->serial_in;

		uart.port.serial_out	= p->serial_out;

		uart.dl_read		= p->dl_read;

		uart.dl_write		= p->dl_write;

		uart.port.handle_irq	= p->handle_irq;

		uart.port.handle_break	= p->handle_break;

		uart.port.set_termios	= p->set_termios;

		uart.port.set_ldisc	= p->set_ldisc;

		uart.port.get_mctrl	= p->get_mctrl;

		uart.port.pm		= p->pm;

		uart.port.dev		= &dev->dev;

		uart.port.irqflags	|= irqflag;

		ret = serial8250_register_8250_port(&uart);

		uart->port.iobase	= p->iobase;

		uart->port.membase	= p->membase;

		uart->port.irq		= p->irq;

		uart->port.irqflags	= p->irqflags;

		uart->port.uartclk	= p->uartclk;

		uart->port.regshift	= p->regshift;

		uart->port.iotype	= p->iotype;

		uart->port.flags		= p->flags;

		uart->port.mapbase	= p->mapbase;

		uart->port.mapsize	= p->mapsize;

		uart->port.hub6		= p->hub6;

		uart->port.has_sysrq	= p->has_sysrq;

		uart->port.private_data	= p->private_data;

		uart->port.type		= p->type;

		uart->bugs		= p->bugs;

		uart->port.serial_in	= p->serial_in;

		uart->port.serial_out	= p->serial_out;

		uart->dl_read		= p->dl_read;

		uart->dl_write		= p->dl_write;

		uart->port.handle_irq	= p->handle_irq;

		uart->port.handle_break	= p->handle_break;

		uart->port.set_termios	= p->set_termios;

		uart->port.set_ldisc	= p->set_ldisc;

		uart->port.get_mctrl	= p->get_mctrl;

		uart->port.pm		= p->pm;

		uart->port.dev		= &dev->dev;

		uart->port.irqflags	|= irqflag;

		ret = serial8250_register_8250_port(uart);

		if (ret < 0) {

			dev_err(&dev->dev, "unable to register port at index %d "

				"(IO%lx MEM%llx IRQ%d): %d\n", i,