diff options
| author |   visa <visa@openbsd.org> | 2019-01-06 12:59:45 +0000 |
|---|---|---|
| committer | visa <visa@openbsd.org> | 2019-01-06 12:59:45 +0000 |
| commit | ec412da11be49c25266553c64da7e06a018ba909 (patch) | |
| tree | 448321fd2d08343c136e4be46e6c0fcbf75db7c3 /sys/kern/sched_bsd.c | |
| parent | Rewrite ip_pcbopts() to fill a fresh mbuf with the ip options instead (diff) | |
| download | wireguard-openbsd-ec412da11be49c25266553c64da7e06a018ba909.tar.xz wireguard-openbsd-ec412da11be49c25266553c64da7e06a018ba909.zip | |
Fix unsafe use of ptsignal() in mi_switch().
ptsignal() has to be called with the kernel lock held. As ensuring the
locking in mi_switch() is not easy, and deferring the signaling using
the task API is not possible because of lock order issues in
mi_switch(), move the CPU time checking into a periodic timer where
the kernel can be locked without issues.
With this change, each process has a dedicated resource check timer.
The timer gets activated only when a CPU time limit is set. Because the
checking is not done as frequently as before, some precision is lost.
Use of timers adapted from FreeBSD.
OK tedu@
Reported-by: syzbot+2f5d62256e3280634623@syzkaller.appspotmail.com
Diffstat (limited to 'sys/kern/sched_bsd.c')
| -rw-r--r-- | sys/kern/sched_bsd.c | 20 |
1 files changed, 1 insertions, 19 deletions
diff --git a/sys/kern/sched_bsd.c b/sys/kern/sched_bsd.c index b4de163a296..1fa5d319988 100644 --- a/sys/kern/sched_bsd.c +++ b/sys/kern/sched_bsd.c @@ -1,4 +1,4 @@ -/* $OpenBSD: sched_bsd.c,v 1.47 2017/12/04 09:38:20 mpi Exp $ */ +/* $OpenBSD: sched_bsd.c,v 1.48 2019/01/06 12:59:45 visa Exp $ */ /* $NetBSD: kern_synch.c,v 1.37 1996/04/22 01:38:37 christos Exp $ */ /*- @@ -336,8 +336,6 @@ mi_switch(void) struct proc *p = curproc; struct proc *nextproc; struct process *pr = p->p_p; - struct rlimit *rlim; - rlim_t secs; struct timespec ts; #ifdef MULTIPROCESSOR int hold_count; @@ -382,22 +380,6 @@ mi_switch(void) tuagg_unlocked(pr, p); /* - * Check if the process exceeds its cpu resource allocation. - * If over max, kill it. - */ - rlim = &pr->ps_limit->pl_rlimit[RLIMIT_CPU]; - secs = pr->ps_tu.tu_runtime.tv_sec; - if (secs >= rlim->rlim_cur) { - if (secs >= rlim->rlim_max) { - psignal(p, SIGKILL); - } else { - psignal(p, SIGXCPU); - if (rlim->rlim_cur < rlim->rlim_max) - rlim->rlim_cur += 5; - } - } - - /* * Process is about to yield the CPU; clear the appropriate * scheduling flags. */ |