Trying to setup the pppd server to use ipoctal's serial ports, it says the ports
are busy the first time. If the operation is repeated, a kernel bug due to a
dereference of a NULL pointer appears.
Removing the one-access-only setup from the driver, removes this kernel bug.
Signed-off-by: Samuel Iglesias Gonsalvez <siglesias@xxxxxxxxxx>
---
drivers/ipack/devices/ipoctal.c | 21 ++-------------------
1 file changed, 2 insertions(+), 19 deletions(-)
diff --git a/drivers/ipack/devices/ipoctal.c b/drivers/ipack/devices/ipoctal.c
index 8f699b0..241db2f 100644
--- a/drivers/ipack/devices/ipoctal.c
+++ b/drivers/ipack/devices/ipoctal.c
@@ -38,7 +38,6 @@ struct ipoctal_channel {
spinlock_t lock;
unsigned int pointer_read;
unsigned int pointer_write;
- atomic_t open;
struct tty_port tty_port;
union scc2698_channel __iomem *regs;
union scc2698_block __iomem *block_regs;
@@ -70,22 +69,12 @@ static int ipoctal_port_activate(struct tty_port *port, struct tty_struct *tty)
static int ipoctal_open(struct tty_struct *tty, struct file *file)
{
- int res;
struct ipoctal_channel *channel;
channel = dev_get_drvdata(tty->dev);
-
- if (atomic_read(&channel->open))
- return -EBUSY;
-
tty->driver_data = channel;
- res = tty_port_open(&channel->tty_port, tty, file);
- if (res)
- return res;
-
- atomic_inc(&channel->open);
- return 0;
+ return tty_port_open(&channel->tty_port, tty, file);
}
static void ipoctal_reset_stats(struct ipoctal_stats *stats)
@@ -111,9 +100,7 @@ static void ipoctal_close(struct tty_struct *tty, struct file *filp)
struct ipoctal_channel *channel = tty->driver_data;
tty_port_close(&channel->tty_port, tty, filp);
-
- if (atomic_dec_and_test(&channel->open))
- ipoctal_free_channel(channel);
+ ipoctal_free_channel(channel);
}
static int ipoctal_get_icount(struct tty_struct *tty,
@@ -205,10 +192,6 @@ static void ipoctal_irq_channel(struct ipoctal_channel *channel)
u8 isr, sr;
struct tty_struct *tty;
- /* If there is no client, skip the check */
- if (!atomic_read(&channel->open))
- return;
-
tty = tty_port_tty_get(&channel->tty_port);
if (!tty)
return;
--
1.7.10.4
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