Re: [PATCH] fbcon: use default if cursor blink interval is not valid

Pavel Machek
2016-05-19T09:01:39Z

Hi!

> Two current [1] and three previous [2] systems locked during boot
> because the cursor flash timer was set using an ops->cur_blink_jiffies
> value of 0. Previous patches attempted to solve the problem by moving
> variable initialization earlier in the setup sequence [2].
>
> Use the normal cursor blink default interval of 200 ms if
> ops->cur_blink_jiffies is not in the range specified in commit
> bd63364caa8d. Since invalid values are not used, specific system
> initialization timings should not cause lockups.
>
> [1] https://bugs.launchpad.net/bugs/1574814
> [2] see commits: 2a17d7e80f1d, f235f664a8af, a1e533ec07d5

Acked-by: Pavel Machek <pavel@ucw.cz>

> static void cursor_timer_handler(unsigned long dev_addr)
> {
> struct fb_info *info = (struct fb_info *) dev_addr;
> struct fbcon_ops *ops = info->fbcon_par;
>
> queue_work(system_power_efficient_wq, &info->queue);
> - mod_timer(&ops->cursor_timer, jiffies + ops->cur_blink_jiffies);
> + mod_timer(&ops->cursor_timer, jiffies +
> + cursor_blink_jiffies(ops->cur_blink_jiffies));
> }
>
> static void fbcon_add_cursor_timer(struct fb_info *info)

And actually... perhaps mod_timer should have some check for too low
timeouts..?

WARN_ON?
Pavel

--
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