mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-08-20 14:16:02 +00:00
Code Issues Releases Wiki Activity

powerpc/hvc_udbg: Don't crash when udbg_putc is NULL

Browse source 
Also while at it, add some help text indicating why you shouldn't
enable that driver under normal circumstances

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Benjamin Herrenschmidt 2012-03-14 18:37:04 +11:00
parent ba7a4822b4
commit 7d3d897a46
2 changed files with 11 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
drivers/tty/hvc/Kconfig
View file

@ -71,6 +71,10 @@ config HVC_UDBG
depends on PPC && EXPERIMENTAL
select HVC_DRIVER
default n
help
This is meant to be used during HW bring up or debugging when
no other console mechanism exist but udbg, to get you a quick
console for userspace. Do NOT enable in production kernels.
config HVC_DCC
bool "ARM JTAG DCC console"

8
drivers/tty/hvc/hvc_udbg.c
View file

@ -36,7 +36,7 @@ static int hvc_udbg_put(uint32_t vtermno, const char *buf, int count)
{
int i;
for (i = 0; i < count; i++)
for (i = 0; i < count && udbg_putc; i++)
udbg_putc(buf[i]);
return i;
@ -67,6 +67,9 @@ static int __init hvc_udbg_init(void)
{
struct hvc_struct *hp;
if (!udbg_putc)
return -ENODEV;
BUG_ON(hvc_udbg_dev);
hp = hvc_alloc(0, NO_IRQ, &hvc_udbg_ops, 16);
@ -88,6 +91,9 @@ module_exit(hvc_udbg_exit);
static int __init hvc_udbg_console_init(void)
{
if (!udbg_putc)
return -ENODEV;
hvc_instantiate(0, 0, &hvc_udbg_ops);
add_preferred_console("hvc", 0, NULL);