ref: acd3ec2e4f218453e36bdabd891215624d9432cc
parent: 74b601a550dacfdcaa78c052fb7c14dbd2b7babb
author: cinap_lenrek <cinap_lenrek@felloff.net>
date: Sat Oct 27 16:00:12 EDT 2018
devuart: don't sleep in uartdrainoutput() when called splhi or without a process uartdrainoutput() might be called in early initialization from uartctl() without a process.
--- a/sys/src/9/port/devuart.c
+++ b/sys/src/9/port/devuart.c
@@ -318,9 +318,8 @@
static void
uartdrainoutput(Uart *p)
{- if(!p->enabled)
+ if(!p->enabled || up == nil || !islo())
return;
-
p->drain = 1;
if(waserror()){p->drain = 0;
--
⑨