From 53c6dbe11903e053d2f947f8baaef535fd54fbd0 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Wed, 25 Sep 2002 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 2002-09-25

---
 port/dev.c     | 2 +-
 port/devcons.c | 3 ++-
 port/proc.c    | 6 ++++--
 port/taslock.c | 2 ++
 4 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/port/dev.c b/port/dev.c
index 9d33988a28a1a46ab8904570fb2dbe6fdb1090b5..3fda0aad34ea256bcbe7e6823a652c7ba56b0560 100644
--- a/port/dev.c
+++ b/port/dev.c
@@ -283,7 +283,7 @@ devdirread(Chan *c, char *d, long n, Dirtab *tab, int ntab, Devgen *gen)
 			dsz = convD2M(&dir, (uchar*)d, n-m);
 			if(dsz <= BIT16SZ){	/* <= not < because this isn't stat; read is stuck */
 				if(m == 0)
-					return -1;
+					error(Eshort);
 				return m;
 			}
 			m += dsz;
diff --git a/port/devcons.c b/port/devcons.c
index f0506ed6b243b0d5813862a4abf848f7715195ff..42005352572f9c5b16304733ef3aab89e44f178f 100644
--- a/port/devcons.c
+++ b/port/devcons.c
@@ -17,6 +17,8 @@ Queue*	kprintoq;		/* console output, for /dev/kprint */
 ulong	kprintinuse;		/* test and set whether /dev/kprint is open */
 int		iprintscreenputs = 1;
 
+int		panicking;
+
 static struct
 {
 	QLock;
@@ -198,7 +200,6 @@ panic(char *fmt, ...)
 	int n;
 	va_list arg;
 	char buf[PRINTSIZE];
-	static int panicking;
 
 	kprintoq = nil;	/* don't try to write to /dev/kprint */
 
diff --git a/port/proc.c b/port/proc.c
index 81cd1c86b40bd1258cd810a8bd12edef8ff8a829..93ee7fa139a80ade0bfea4d1287db225ca34f90d 100644
--- a/port/proc.c
+++ b/port/proc.c
@@ -91,10 +91,12 @@ schedinit(void)		/* never returns */
 void
 sched(void)
 {
+	int x[1];
+
 	if(m->ilockdepth)
-		panic("ilockdepth %d, last lock 0x%p at 0x%lux",
+		panic("ilockdepth %d, last lock 0x%p at 0x%lux, sched called from 0x%lux",
 			m->ilockdepth, up?up->lastilock:nil,
-			(up && up->lastilock)?up->lastilock->pc:0);
+			(up && up->lastilock)?up->lastilock->pc:0, getcallerpc(x+3));
 
 	if(up){
 		if(up->nlocks && up->state != Moribund){
diff --git a/port/taslock.c b/port/taslock.c
index f6a69ccccddfb1203f1bdd9666d17a695ccc88c4..fd70e120f46d15f406fe0f7eea75549e4fec3c00 100644
--- a/port/taslock.c
+++ b/port/taslock.c
@@ -185,5 +185,7 @@ iunlock(Lock *l)
 
 	m->splpc = getcallerpc(&l);
 	m->ilockdepth--;
+	if(up)
+		up->lastilock = nil;
 	splxpc(sr);
 }