shithub: riscv

Info  •  Files  •  Log  •  Branches

fix race condition of the CCACHE flag by clearing the flag in
attachimage() instead of temporarily reseting in pio().

--- a/sys/src/9/port/fault.c

+++ b/sys/src/9/port/fault.c

@@ -200,7 +200,7 @@

 	Page *new;

 	KMap *k;

 	Chan *c;

-	int n, ask, cache;

+	int n, ask;

 	char *kaddr;

 	ulong daddr;

 	Page *loadrec;

@@ -238,9 +238,7 @@

 	k = kmap(new);

 	kaddr = (char*)VA(k);

-	cache = c->flag & CCACHE;

 	while(waserror()) {

-		c->flag |= cache;

 		if(strcmp(up->errstr, Eintr) == 0)

 			continue;

 		kunmap(k);

@@ -247,9 +245,7 @@

 		putpage(new);

 		faulterror(Eioload, c, 0);

 	}

-	c->flag &= ~CCACHE;

 	n = devtab[c->type]->read(c, kaddr, ask, daddr);

-	c->flag |= cache;

 	if(n != ask)

 		faulterror(Eioload, c, 0);

 	if(ask < BY2PG)

--- a/sys/src/9/port/segment.c

+++ b/sys/src/9/port/segment.c

@@ -287,6 +287,7 @@

 	lock(i);

 	incref(c);

+	c->flag &= ~CCACHE;

 	i->c = c;

 	i->type = c->type;

 	i->qid = c->qid;