On Mon, 04 Jan 2010, Carlos O'Donell wrote: > On Mon, Jan 4, 2010 at 12:32 PM, John David Anglin > <dave@xxxxxxxxxxxxxxxxxx> wrote: > >> e) Thus the child either crashes, overwrites memory of the parent or does other things wrong. > > > > I don't see how the forked child can affect the memory of the parent. > > It can close files and affect the parent that way (child should use > > _exit and not exit). > > > > If the forked child actually overwrites memory of the parent, this is > > a big bug in the linux fork code. > > We have two bugs that are getting mixed here. > > Your original post has to do with a futex wait failure, this is > possibly related to the hppa low level lock implementation. I am > updating the hppa implementation to see if I can fix this for you. > > Helge's comments relate only to the vfork crash, and the Qt thread > creation issue being seen by debian. I was talking about the debian thread creation bug in the above. I haven't been able to duplicate the vfork crash that you posted. The expect/tcl futex bug is likely related to the debian bug (this is what expect does in testsuite runs). Reduced minifail testcase is below. Dave -- J. David Anglin dave.anglin@xxxxxxxxxxxxxx National Research Council of Canada (613) 990-0752 (FAX: 952-6602) #include <pthread.h> #include <unistd.h> #include <stdio.h> #include <stdlib.h> /* http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=561203 clone(child_stack=0x4088d040, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, parent_tidptr=0x4108c4e8, tls=0x4108c900, child_tidptr=0x4108c4e8) = 14819 [pid 14819] set_robust_list(0x4108c4f0, 0xc) = 0 [pid 14818] clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x40002028) = 14820 g++ minifail.cpp -o minifail -O0 -pthread -g i=0; while true; do i=$(($i+1)); echo Run $i; ./minifail; done; */ void* thread_run(void* arg) { write(1,"Thread OK.\n",11); } int pure_test() { pthread_t thread; pthread_create(&thread, NULL, thread_run, NULL); switch (fork()) { case -1: perror("fork() failed"); case 0: write(1,"Child OK.\n",10); _exit(0); default: break; } pthread_join(thread, NULL); return 0; } int main(int argc, char** argv) { return pure_test(); } -- To unsubscribe from this list: send the line "unsubscribe linux-parisc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
