On Tue, Jun 30, 2020 at 12:08:03PM +0200, Martin Pieuchot wrote:
> On 29/06/20(Mon) 11:59, Vitaliy Makkoveev wrote:
> > [...]
> > I reworked tool for reproduce. Now I avoided fork()/exec() route and it
> > takes couple of minutes to take panic on 4 cores. Also some screenshots
> > attached.
>
> Setting kern.pool_debug=2 makes the race reproducible in seconds.
>
> Could you turn this test into something committable in regress/? We can
> link it to the build once a fix is committed.
>
We have 3 races with cloned interfaces:
1. if_clone_create() vs if_clone_create()
2. if_clone_destroy() vs if_clone_destroy()
3. if_clone_destroy() vs the rest of stack
It makes sences to commit unified test to regress/, so I suggest to wait
a little.
> > #include <sys/socket.h>
> > #include <sys/ioctl.h>
> > #include <net/if.h>
> > #include <stdio.h>
> > #include <stdlib.h>
> > #include <err.h>
> > #include <errno.h>
> > #include <pthread.h>
> > #include <string.h>
> > #include <unistd.h>
> >
> > static struct ifreq ifr;
> >
> > static void *clone_create(void *arg)
> > {
> > int s;
> >
> > if((s=socket(AF_INET, SOCK_DGRAM, 0))<0)
> > err(1, "socket()");
> > while(1){
> > if(ioctl(s, SIOCIFCREATE, &ifr)<0)
> > if(errno==EINVAL)
> > exit(1);
> > }
> >
> > return NULL;
> > }
> >
> > static void *clone_destroy(void *arg)
> > {
> > int s;
> >
> > if((s=socket(AF_INET, SOCK_DGRAM, 0))<0)
> > err(1, "socket()");
> > while(1){
> > if(ioctl(s, SIOCIFDESTROY, &ifr)<0)
> > if(errno==EINVAL)
> > exit(1);
> > }
> >
> > return NULL;
> > }
> >
> > int main(int argc, char *argv[])
> > {
> > pthread_t thr;
> > int i;
> >
> > if(argc!=2){
> > fprintf(stderr, "usage: %s ifname\n", getprogname());
> > return 1;
> > }
> >
> > if(getuid()!=0){
> > fprintf(stderr, "should be root\n");
> > return 1;
> > }
> >
> > memset(&ifr, 0, sizeof(ifr));
> > strlcpy(ifr.ifr_name, argv[1], sizeof(ifr.ifr_name));
> >
> > for(i=0; i<8*4; ++i){
> > if(pthread_create(&thr, NULL, clone_create, NULL)!=0)
> > errx(1, "pthread_create(clone_create)");
> > }
> >
> > clone_destroy(NULL);
> >
> > return 0;
> > }
> >
> > ---- cut end ----
>
>
>
>
>
