metropolis: prevent printk console pollution
This implements two separate approaches to limit printk pollution of the
new tconsole:
1. Sets the minimum printk level to EMERG. Everything lower than this
level will not get blasted to tty0.
2. Jut in case something does a spurious EMERG printk (or something
just writes to tty0), we redraw the console. This makes it
self-healing.
Change-Id: I69370ebf6c3cb3cacc8b6ea1ad3703e758bbf50c
Reviewed-on: https://review.monogon.dev/c/monogon/+/3398
Tested-by: Jenkins CI
Reviewed-by: Lorenz Brun <lorenz@monogon.tech>
diff --git a/metropolis/node/core/tconsole/tconsole.go b/metropolis/node/core/tconsole/tconsole.go
index bbdca82..bd4bd08 100644
--- a/metropolis/node/core/tconsole/tconsole.go
+++ b/metropolis/node/core/tconsole/tconsole.go
@@ -159,8 +159,13 @@
// Ticker used to maintain redraws at minimum 10Hz, to eg. update the clock in
// the status bar.
- ticker := time.NewTicker(time.Second / 10)
- defer ticker.Stop()
+ tickerDraw := time.NewTicker(time.Second / 10)
+ defer tickerDraw.Stop()
+
+ // Ticker used to fully resync the screen every 10 seconds, in case something
+ // scribbled over the TTY.
+ tickerSync := time.NewTicker(time.Second * 10)
+ defer tickerSync.Stop()
for {
// Draw active page.
@@ -174,7 +179,9 @@
c.screen.Show()
select {
- case <-ticker.C:
+ case <-tickerDraw.C:
+ case <-tickerSync.C:
+ c.screen.Sync()
case <-ctx.Done():
return ctx.Err()
case ev := <-evC: