mxser_new, alter locking in isr
Avoid oopsing when stress-testing open/close -- port->tty is NULL
sometimes, but is expected to be non-NULL, since dereferencing.
Receive/transmit chars iff ASYNC_CLOSING is not set and ASYNC_INITIALIZED
is set. Thanks Sergei for pointing this out and testing.
Cc: Sergei Organov <[EMAIL PROTECTED]>
Signed-off-by: Jiri Slaby <[EMAIL PROTECTED]>
---
commit 15e7e157283a86bb819a0193a8cb137d7640d3a6
tree c0d4130f898c835c4e283af0e343ee504345d4c0
parent ab35af25a3d01f1e07fc8de5b96f484b93a8ad2a
author Jiri Slaby <[EMAIL PROTECTED]> Fri, 29 Dec 2006 20:00:21 +0059
committer Jiri Slaby <[EMAIL PROTECTED]> Fri, 29 Dec 2006 20:00:21 +0059
drivers/char/mxser_new.c | 22 +++++++++-------------
1 file changed, 9 insertions(+), 13 deletions(-)
diff --git a/drivers/char/mxser_new.c b/drivers/char/mxser_new.c
index 8da8833..ec61cf8 100644
--- a/drivers/char/mxser_new.c
+++ b/drivers/char/mxser_new.c
@@ -2073,9 +2073,6 @@ static void mxser_receive_chars(struct mxser_port *port,
int *status)
int cnt = 0;
int recv_room;
int max = 256;
- unsigned long flags;
-
- spin_lock_irqsave(&port->slock, flags);
recv_room = tty->receive_room;
if ((recv_room == 0) && (!port->ldisc_stop_rx))
@@ -2159,7 +2156,6 @@ end_intr:
mxvar_log.rxcnt[port->tty->index] += cnt;
port->mon_data.rxcnt += cnt;
port->mon_data.up_rxcnt += cnt;
- spin_unlock_irqrestore(&port->slock, flags);
tty_flip_buffer_push(tty);
}
@@ -2167,9 +2163,6 @@ end_intr:
static void mxser_transmit_chars(struct mxser_port *port)
{
int count, cnt;
- unsigned long flags;
-
- spin_lock_irqsave(&port->slock, flags);
if (port->x_char) {
outb(port->x_char, port->ioaddr + UART_TX);
@@ -2178,11 +2171,11 @@ static void mxser_transmit_chars(struct mxser_port
*port)
port->mon_data.txcnt++;
port->mon_data.up_txcnt++;
port->icount.tx++;
- goto unlock;
+ return;
}
if (port->xmit_buf == 0)
- goto unlock;
+ return;
if ((port->xmit_cnt <= 0) || port->tty->stopped ||
(port->tty->hw_stopped &&
@@ -2190,7 +2183,7 @@ static void mxser_transmit_chars(struct mxser_port *port)
(!port->board->chip_flag))) {
port->IER &= ~UART_IER_THRI;
outb(port->IER, port->ioaddr + UART_IER);
- goto unlock;
+ return;
}
cnt = port->xmit_cnt;
@@ -2215,8 +2208,6 @@ static void mxser_transmit_chars(struct mxser_port *port)
port->IER &= ~UART_IER_THRI;
outb(port->IER, port->ioaddr + UART_IER);
}
-unlock:
- spin_unlock_irqrestore(&port->slock, flags);
}
/*
@@ -2257,12 +2248,16 @@ static irqreturn_t mxser_interrupt(int irq, void
*dev_id)
port = &brd->ports[i];
int_cnt = 0;
+ spin_lock(&port->slock);
do {
iir = inb(port->ioaddr + UART_IIR);
if (iir & UART_IIR_NO_INT)
break;
iir &= MOXA_MUST_IIR_MASK;
- if (!port->tty) {
+ if (!port->tty ||
+ (port->flags & ASYNC_CLOSING) ||
+ !(port->flags &
+ ASYNC_INITIALIZED)) {
status = inb(port->ioaddr + UART_LSR);
outb(0x27, port->ioaddr + UART_FCR);
inb(port->ioaddr + UART_MSR);
@@ -2308,6 +2303,7 @@ static irqreturn_t mxser_interrupt(int irq, void *dev_id)
mxser_transmit_chars(port);
}
} while (int_cnt++ < MXSER_ISR_PASS_LIMIT);
+ spin_unlock(&port->slock);
}
if (pass_counter++ > MXSER_ISR_PASS_LIMIT)
break; /* Prevent infinite loops */
-
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