4.2.8-ckt6 -stable review patch. If anyone has any objections, please let me know.
---8<------------------------------------------------------------ From: Jean-Philippe Brucker <[email protected]> commit a1e533ec07d583d01349ef13c0c965b8633e1b91 upstream. Since commit 27a4c827c34ac4256a190cc9d24607f953c1c459 fbcon: use the cursor blink interval provided by vt two attempts have been made at fixing a possible hang caused by cursor_timer_handler. That function registers a timer to be triggered at "jiffies + fbcon_ops.cur_blink_jiffies". A new case had been encountered during initialisation of clcd-pl11x: fbcon_fb_registered do_fbcon_takeover -> do_register_con_driver fbcon_startup (A) add_cursor_timer (with cur_blink_jiffies = 0) -> do_bind_con_driver visual_init fbcon_init (B) cur_blink_jiffies = msecs_to_jiffies(vc->vc_cur_blink_ms); If we take an softirq anywhere between A and B (and we do), cursor_timer_handler executes indefinitely. Instead of patching all possible paths that lead to this case one at a time, fix the issue at the source and initialise cur_blink_jiffies to 200ms when allocating fbcon_ops. This was its default value before aforesaid commit. fbcon_cursor or fbcon_init will refine this value downstream. Signed-off-by: Jean-Philippe Brucker <[email protected]> Tested-by: Scot Doyle <[email protected]> Signed-off-by: Tomi Valkeinen <[email protected]> Signed-off-by: Kamal Mostafa <[email protected]> --- drivers/video/console/fbcon.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c index 92f3949..6e92917 100644 --- a/drivers/video/console/fbcon.c +++ b/drivers/video/console/fbcon.c @@ -709,6 +709,7 @@ static int con2fb_acquire_newinfo(struct vc_data *vc, struct fb_info *info, } if (!err) { + ops->cur_blink_jiffies = HZ / 5; info->fbcon_par = ops; if (vc) @@ -956,6 +957,7 @@ static const char *fbcon_startup(void) ops->currcon = -1; ops->graphics = 1; ops->cur_rotate = -1; + ops->cur_blink_jiffies = HZ / 5; info->fbcon_par = ops; p->con_rotate = initial_rotation; set_blitting_type(vc, info); -- 2.7.0
