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author | Jan Kiszka <jan.kiszka@siemens.com> | 2015-05-05 06:26:27 (GMT) |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-05-10 17:10:07 (GMT) |
commit | 59cfc45f17d6d1dda2990e6f5a94df24a18330b8 (patch) | |
tree | 37c05b196a9f91f8c28a9c1a4e585ec5973650e4 /drivers/tty/serial/8250 | |
parent | 24ee4df12216a0b1c9a0c22f83fbf366eb216d33 (diff) | |
download | linux-59cfc45f17d6d1dda2990e6f5a94df24a18330b8.tar.xz |
serial: 8250: Do nothing if nr_uarts=0
When nr_uarts was set to 0 (via config or 8250_core.nr_uarts), we crash
early on x86 because serial8250_isa_init_ports dereferences base_ops
which remains NULL. In fact, there is nothing to do for all the callers
of serial8250_isa_init_ports if there are no uarts.
Based on suggestions by Peter Hurley.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/8250')
-rw-r--r-- | drivers/tty/serial/8250/8250_core.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index 01cecd5..5521ff8 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -3535,6 +3535,9 @@ static struct console univ8250_console = { static int __init univ8250_console_init(void) { + if (nr_uarts == 0) + return -ENODEV; + serial8250_isa_init_ports(); register_console(&univ8250_console); return 0; @@ -3565,7 +3568,7 @@ int __init early_serial_setup(struct uart_port *port) { struct uart_port *p; - if (port->line >= ARRAY_SIZE(serial8250_ports)) + if (port->line >= ARRAY_SIZE(serial8250_ports) || nr_uarts == 0) return -ENODEV; serial8250_isa_init_ports(); @@ -3932,6 +3935,9 @@ static int __init serial8250_init(void) { int ret; + if (nr_uarts == 0) + return -ENODEV; + serial8250_isa_init_ports(); printk(KERN_INFO "Serial: 8250/16550 driver, " |