Re: [PATCH] oom kill init lead panic

From	Michal Hocko <mhocko@kernel.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH] oom kill init lead panic
Date	2015-12-02 11:40 +0100
Message-ID	<qBcZk-5WX-3@gated-at.bofh.it> (permalink)
References	<qB9f4-3xt-5@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

On Wed 02-12-15 14:30:56, chenjie6@huawei.com wrote:
> From: chenjie <chenjie6@huawei.com>
> 
> 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.

It is quite unlikely that killing the task would help to free much
memory so if this is really the only oom victim it is to be expected to
panic sooner or later but this is in line with oom_unkillable_task()
so it makes sense.
 
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Chen Jie <chenjie6@huawei.com>

Acked-by: Michal Hocko <mhocko@suse.com>

> 
> ---
>  mm/oom_kill.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/mm/oom_kill.c b/mm/oom_kill.c
> index d13a339..a0ddebd 100644
> --- a/mm/oom_kill.c
> +++ b/mm/oom_kill.c
> @@ -608,6 +608,8 @@ void oom_kill_process(struct oom_control *oc, struct task_struct *p,
>  			continue;
>  		if (unlikely(p->flags & PF_KTHREAD))
>  			continue;
> +		if (!is_global_init(p))
> +			continue;
>  		if (p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
>  			continue;
>  
> -- 
> 1.8.0
> 
> --
> 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: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

-- 
Michal Hocko
SUSE Labs
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Thread

[PATCH] oom kill init lead panic <chenjie6@huawei.com> - 2015-12-02 07:40 +0100
  Re: [PATCH] oom kill init lead panic Michal Hocko <mhocko@kernel.org> - 2015-12-02 11:40 +0100
  Re: [PATCH] oom kill init lead panic Greg KH <greg@kroah.com> - 2015-12-02 16:50 +0100

csiph-web