From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH] bugfix oom kill init lead panic To: Andrew Morton References: <1448880869-20506-1-git-send-email-chenjie6@huawei.com> <20151129190802.dc66cf35.akpm@linux-foundation.org> CC: , , , , , From: "Chenjie (K)" Message-ID: <565BC23F.6070302@huawei.com> Date: Mon, 30 Nov 2015 11:27:59 +0800 MIME-Version: 1.0 In-Reply-To: <20151129190802.dc66cf35.akpm@linux-foundation.org> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: My kernel version is 3.10 ,but the 4.3 is the same and the newest code is for_each_process(p) { if (!process_shares_mm(p, mm)) continue; if (same_thread_group(p, victim)) continue; if (unlikely(p->flags & PF_KTHREAD)) continue; if (p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) continue; so this not add the ！is_global_init also. when we vfork (CLONE_VM) a process,the copy_mm if (clone_flags & CLONE_VM) { atomic_inc(&oldmm->mm_users); mm = oldmm; goto good_mm; } use the parent mm. On 2015/11/30 11:08, Andrew Morton wrote: > On Mon, 30 Nov 2015 18:54:29 +0800 wrote: > >> From: chenjie >> >> when oom happened we can see: >> Out of memory: Kill process 9134 (init) score 3 or sacrifice child >> Killed process 9134 (init) total-vm:1868kB, anon-rss:84kB, file-rss:572kB >> Kill process 1 (init) sharing same memory >> ... >> Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009 >> >> That's because: >> the busybox init will vfork a process,oom_kill_process found >> the init not the children,their mm is the same when vfork. >> >> ... >> >> --- a/mm/oom_kill.c >> +++ b/mm/oom_kill.c >> @@ -513,7 +513,7 @@ void oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, >> rcu_read_lock(); >> for_each_process(p) >> if (p->mm == mm && !same_thread_group(p, victim) && >> - !(p->flags & PF_KTHREAD)) { >> + !(p->flags & PF_KTHREAD) && !is_global_init(p)) { >> if (p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) >> continue; > > What kernel version are you using? > > I don't think this can happen in current code... > > . > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org