On 05/11/2017 11:41 AM, Sergey Senozhatsky wrote:
On (05/11/17 17:24), Sergey Senozhatsky wrote:
On (05/09/17 10:29), Sabrina Dubroca wrote:
[..]
That's caused a change of behavior in my qemu setup, with this cmdline
root=/dev/sda1 console=ttyS1 console=ttyS0
Before, the kernel logs appeared on ttyS1, and I logged in with ttyS0
(with my setup, ttyS1 is a file and ttyS0 is unix socket). Now, the
kernel logs go to ttyS0. I need to swap the two console= parameters to
restore behavior.
There might be some other problem (in qemu?) though, because adding
console=tty0 anywhere on that cmdline makes the logs appear on both
tty0 and one ttyS* (but only one of them, and the ordering of the
ttyS* matters).
thanks for the report.
so we have ttyS1 first and ttyS0 last.
after commit in question, register_console() iterates console_cmdline
in reverse order so we see ttyS0 first, then we hit `if (newcon->index < 0)'
condition, set newcon to ttyS0, because we iterate in reverse order now, and
break out. so we enable ttyS0, instead of ttyS1.
previously, we iterated console_cmdline from index 0 and saw ttyS1 first.
so the same `if (newcon->index < 0)' condition would set newcone to ttyS1,
and, thus, we would enable ttyS1, not ttyS0.
Alexey,
can we have preferred console at offset 0 (not at console_cmdline_cnt - 1)
and restore the previous register_console() iteration order?
I don't quite understand what is the problem. Give me more time please.
I hope I will be able to look at this on the weekend.
Thank you
Aleksey Makarov
