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| author | Geert Uytterhoeven <geert@linux-m68k.org> | 2013-11-22 16:47:26 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-01-08 09:42:10 -0800 |
| commit | 34ee0e8ad09ec1e58858bd3c8756a31a2b3c46bf (patch) | |
| tree | 962747d78c55486a8daaec2191a5154214650c02 | |
| parent | 7898047084bed6716bbc2c08b969ddf364ca36fd (diff) | |
| download | lwn-34ee0e8ad09ec1e58858bd3c8756a31a2b3c46bf.tar.gz lwn-34ee0e8ad09ec1e58858bd3c8756a31a2b3c46bf.zip | |
TTY: pmac_zilog, check existence of ports in pmz_console_init()
commit dc1dc2f8a5dd863bf2e79f338fc3ae29e99c683a upstream.
When booting a multi-platform m68k kernel on a non-Mac with "console=ttyS0"
on the kernel command line, it crashes with:
Unable to handle kernel NULL pointer dereference at virtual address (null)
Oops: 00000000
PC: [<0013ad28>] __pmz_startup+0x32/0x2a0
...
Call Trace: [<002c5d3e>] pmz_console_setup+0x64/0xe4
The normal tty driver doesn't crash, because init_pmz() checks
pmz_ports_count again after calling pmz_probe().
In the serial console initialization path, pmz_console_init() doesn't do
this, causing the driver to crash later.
Add a check for pmz_ports_count to fix this.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Finn Thain <fthain@telegraphics.com.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/serial/pmac_zilog.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/tty/serial/pmac_zilog.c b/drivers/tty/serial/pmac_zilog.c index 333c8d012b0e..3f93c47d50bb 100644 --- a/drivers/tty/serial/pmac_zilog.c +++ b/drivers/tty/serial/pmac_zilog.c @@ -2051,6 +2051,9 @@ static int __init pmz_console_init(void) /* Probe ports */ pmz_probe(); + if (pmz_ports_count == 0) + return -ENODEV; + /* TODO: Autoprobe console based on OF */ /* pmz_console.index = i; */ register_console(&pmz_console); |