diff options
| author | Jiri Slaby <jirislaby@gmail.com> | 2007-02-10 01:45:18 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-02-11 10:51:29 -0800 |
| commit | f574874bc861414bbae220b1fe623cbdd098243b (patch) | |
| tree | f905e9170338a295e897013c9ab01ca189f08dbe | |
| parent | 765d94c1b37d08be02eea6abbff70c0fda0ba984 (diff) | |
| download | linux-f574874bc861414bbae220b1fe623cbdd098243b.tar.bz2 | |
[PATCH] Char: 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 <osv@javad.com>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | drivers/char/mxser_new.c | 22 |
1 files changed, 9 insertions, 13 deletions
diff --git a/drivers/char/mxser_new.c b/drivers/char/mxser_new.c index 8da883340dd6..ec61cf81b7e6 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 */ |