Hi folks.

I spent some time on the problem in $subj and found some solution that seems to be working but i'm not sure about it's architectural correctness because libc was changed little bit ;)

here it is:

# diff -u -r lib lib.patched diff -u -r lib/libc/stdlib/malloc.c lib.patched/libc/stdlib/malloc.c --- lib/libc/stdlib/malloc.c Sun Feb 27 22:46:16 2005 +++ lib.patched/libc/stdlib/malloc.c Wed Mar 2 19:55:24 2005 @@ -74,7 +74,7 @@ */ # include "libc_private.h" # include "spinlock.h" - static spinlock_t thread_lock = _SPINLOCK_INITIALIZER; + spinlock_t thread_lock = _SPINLOCK_INITIALIZER; spinlock_t *__malloc_lock = &thread_lock; # define _MALLOC_LOCK() if (__isthreaded)
_SPINLOCK(&thread_lock); # define _MALLOC_UNLOCK() if (__isthreaded)
_SPINUNLOCK(&thread_lock); diff -u -r lib/libc_r/uthread/uthread_fork.c
lib.patched/libc_r/uthread/uthread_fork.c --- lib/libc_r/uthread/uthread_fork.c Fri Dec 10 09:06:45 2004 +++ lib.patched/libc_r/uthread/uthread_fork.c Wed Mar 2 20:10:49 2005 @@ -61,6 +61,8 @@ _thread_kern_sig_defer();

_pthread_mutex_lock(&_atfork_mutex); + extern spinlock_t thread_lock; + _SPINLOCK(&thread_lock);

/* Run down atfork prepare handlers. */ TAILQ_FOREACH_REVERSE(af, &_atfork_list, atfork_head, qe) { @@ -70,6 +72,8 @@

/* Fork a new process: */ if ((ret = __sys_fork()) != 0) { + _SPINUNLOCK(&thread_lock); + /* Run down atfork parent handlers. */ TAILQ_FOREACH(af, &_atfork_list, qe) { if (af->parent != NULL) @@ -78,6 +82,8 @@ _pthread_mutex_unlock(&_atfork_mutex);

} else { + _SPINUNLOCK(&thread_lock); + /* Close the pthread kernel pipe: */ __sys_close(_thread_kern_pipe[0]); __sys_close(_thread_kern_pipe[1]);

The main problem with it is that after fork child inherits from the parent inconsist heap. So the obvious solution is to synchronyze the fork and heap manipulations. I didn't find the easyest way how to get the lock variable from malloc lib as to open this variable deleting static spec.

So what do you think guys about this patch?