empire/empserver
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Fix LWP's stack initialization for -s

Browse source 
With -s, LWP initializes thread stacks to track stack use.  It did
that after makecontext(), with disastrous results on systems where
makecontext() writes something to the stack that swapcontext() expects
to find there.  Makes FreeBSD 6.2 crash in swapcontext().

Factor stack allocation out of lwpNewContext() into lwpNewStack().
Move call of lwpStackCheckInit() into lwpNewStack().
This commit is contained in:
Markus Armbruster 2008-02-14 23:47:27 +01:00
parent 40eb78eb74
commit 5c2f7646e1
3 changed files with 33 additions and 27 deletions
Download patch file Download diff file Expand all files Collapse all files

32
src/lib/lwp/lwp.c
View file

@ -127,6 +127,32 @@ lwpEntryPoint(void)
lwpExit();
}
static int
lwpNewStack(struct lwpProc *newp, int stacksz)
{
char *s;
int size, redsize;
/* Make size a multiple of sizeof(long) to keep things aligned */
stacksz = (stacksz + sizeof(long) - 1) & -sizeof(long);
/* Add a red zone on each side of the stack for LWP_STACKCHECK */
redsize = newp->flags & LWP_STACKCHECK ? LWP_REDZONE : 0;
size = stacksz + 2 * redsize;
s = malloc(size);
if (!s)
return -1;
newp->sbtm = s;
newp->size = size;
newp->ustack = s + redsize;
newp->usize = stacksz;
if (newp->flags & LWP_STACKCHECK)
lwpStackCheckInit(newp);
return 0;
}
/*
* lwpCreate -- create a process.
*/
@ -147,19 +173,19 @@ lwpCreate(int priority, void (*entry)(void *), int stacksz,
newp->dead = 0;
newp->runtime = (time_t)-1;
newp->fd = -1;
newp->sbtm = NULL;
if (LWP_MAX_PRIO <= priority)
priority = LWP_MAX_PRIO - 1;
if (LwpMaxpri < (newp->pri = priority))
LwpMaxpri = priority;
if (lwpNewContext(newp, stacksz) < 0) {
if (lwpNewStack(newp, stacksz) < 0 || lwpNewContext(newp) < 0) {
free(newp->sbtm);
free(newp->name);
free(newp);
return NULL;
}
lwpStatus(newp, "creating process structure %p (sbtm %p)",
newp, newp->sbtm);
if (flags & LWP_STACKCHECK)
lwpStackCheckInit(newp);
lwpReady(newp);
lwpReady(LwpCurrent);
lwpReschedule();