Messages in this thread | | | Date | Sun, 12 Feb 2012 01:02:11 +0000 | From | Al Viro <> | Subject | Re: your mail |
| |
On Sun, Feb 12, 2012 at 01:21:10AM +0100, Richard Weinberger wrote:
Not a full review by any means, but...
> +++ b/arch/um/drivers/line.c > @@ -19,19 +19,29 @@ static irqreturn_t line_interrupt(int irq, void *data) > { > struct chan *chan = data; > struct line *line = chan->line; > + struct tty_struct *tty; > + > + if (line) { > + tty = tty_port_tty_get(&line->port); > + chan_interrupt(&line->chan_list, &line->task, tty, irq); > + tty_kref_put(tty); > + } > > - if (line) > - chan_interrupt(&line->chan_list, &line->task, line->tty, irq); > return IRQ_HANDLED; > }
Is tty_kref_put() safe in interrupt? Here it seems to be OK, but in other callers... More or less at random: drivers/tty/serial/lantiq.c has it called from lqasc_rx_int(). It seems to be possible to have it end up calling ->ops->shutdown() and in this case that'd be lqasc_shutdown(). Which does a bunch of free_irq(), including the ->rx_irq, i.e. the one we have it called from. Alan?
> @@ -495,13 +413,6 @@ static int setup_one_line(struct line *lines, int n, char *init, int init_prio, > struct line *line = &lines[n]; > int err = -EINVAL; > > - spin_lock(&line->count_lock); > - > - if (line->count) { > - *error_out = "Device is already open"; > - goto out; > - }
... and similar in line_open() - just what happens if you try to reconfigure an opened one?
> @@ -612,13 +523,15 @@ int line_get_config(char *name, struct line *lines, unsigned int num, char *str, > > line = &lines[dev]; > > - spin_lock(&line->count_lock); > + tty = tty_port_tty_get(&line->port); > + > if (!line->valid) > CONFIG_CHUNK(str, size, n, "none", 1); > - else if (line->tty == NULL) > + else if (tty == NULL) > CONFIG_CHUNK(str, size, n, line->init_str, 1); > else n = chan_config_string(&line->chan_list, str, size, error_out); > - spin_unlock(&line->count_lock); > + > + tty_kref_put(tty);
again, where's the exclusion with config changes?
| |