Re: [RFC PATCH kernel] Revert "fbcon: use the cursor blink interval provided by vt"

On 29/06/16 18:31, Benjamin Herrenschmidt wrote:

On Wed, 2016-06-29 at 18:29 +1000, Benjamin Herrenschmidt wrote:

quoted

On Wed, 2016-06-29 at 18:19 +1000, Alexey Kardashevskiy wrote:

quoted

This is rather a bugreport than actual revert but nevertheless.

Since 27a4c827c34a I started noticing weird traces and quite often
I could not boot my test machine which is POWER8 box with AST video
or ATI video (video adapter type does not matter much although
is happens lot more often with the OpenPOWER machine which got
AST).
The system console is IPMI, not the actual video adapter.

I bisected it to this:

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/com
mi
t/?id'a4c827c34ac4256a190cc9d24607f953c1c459

For some reason which I do not understand, in
cursor_timer_handler(),
ops->cur_blink_jiffies is zero. Why can this happen? What is a
proper
fix? Thanks.

Rings a bell... do you have fbcon: initialize blink interval before
calling fb_set_par (f235f664a8afabccf863a5dee4777d2d7b676fda) ?

Also check if you have:

"fbcon: set a default value to blink interval"
(upstream ID a1e533ec07d583d01349ef13c0c965b8633e1b91).

Yes, both. The problem I see appears from v4.4 till the very recent
upstream kernel which I am debugging now and which is v4.7-rc5.


-- 
Alexey