armbian/linux-rockchip
0
0
Fork 0
mirror of https://github.com/armbian/linux-rockchip.git synced 2026-01-06 11:08:10 -08:00
Code Issues Packages Projects Releases Wiki Activity

serial: 8250_port: Check IRQ data before use

Browse Source 
commit cce7fc8b29961b64fadb1ce398dc5ff32a79643b upstream.

In case the leaf driver wants to use IRQ polling (irq = 0) and
IIR register shows that an interrupt happened in the 8250 hardware
the IRQ data can be NULL. In such a case we need to skip the wake
event as we came to this path from the timer interrupt and quite
likely system is already awake.

Without this fix we have got an Oops:

    serial8250: ttyS0 at I/O 0x3f8 (irq = 0, base_baud = 115200) is a 16550A
    ...
    BUG: kernel NULL pointer dereference, address: 0000000000000010
    RIP: 0010:serial8250_handle_irq+0x7c/0x240
    Call Trace:
     ? serial8250_handle_irq+0x7c/0x240
     ? __pfx_serial8250_timeout+0x10/0x10

Fixes: 0ba9e3a13c6a ("serial: 8250: Add missing wakeup event reporting")
Cc: stable <stable@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20230831222555.614426-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Andy Shevchenko
2023-09-01 01:25:55 +03:00
committed by Greg Kroah-Hartman
parent 6d5c886293
commit e14afa4450
1 changed files with 4 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
drivers/tty/serial/8250/8250_port.c
View File

@@ -1914,7 +1914,10 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir)
skip_rx = true;
if (status & (UART_LSR_DR | UART_LSR_BI) && !skip_rx) {
if (irqd_is_wakeup_set(irq_get_irq_data(port->irq)))
struct irq_data *d;
d = irq_get_irq_data(port->irq);
if (d && irqd_is_wakeup_set(d))
pm_wakeup_event(tport->tty->dev, 0);
if (!up->dma || handle_rx_dma(up, iir))
status = serial8250_rx_chars(up, status);