From: zhang.yi20@zte.com.cn
To: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <htejun@gmail.com>, lkml <linux-kernel@vger.kernel.org>,
Ingo Molnar <mingo@redhat.com>, Oleg Nesterov <oleg@redhat.com>,
Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
pang.xunlei@zte.com.cn
Subject: [PATCH]: exec: avoid propagating PF_NO_SETAFFINITY into userspace child
Date: Fri, 29 Nov 2013 17:19:21 +0800 [thread overview]
Message-ID: <OF0BCEFABA.AA93B98E-ON48257C32.0031CD54-48257C32.00334133@zte.com.cn> (raw)
Khelper is a workqueue thread which has PF_NO_SETAFFINITY set.
When a usermode process is spawned by khelper through __call_usermodehelper()
which will invoke kernel_thread() (not kthread_create()) to fork the new
process, we will clearly see that it will inherit the PF_NO_SETAFFINITY flag.
Consequently, this usermod process will lose some capabilities like
sched_setaffinity(), moving between cgroups, etc.
Clearing this flag in flush_old_exec() to solve this problem.
Signed-off-by: Zhang Yi <zhang.yi20@zte.com.cn>
Signed-off-by: Pang Xunlei <pang.xunlei@zte.com.cn>
--- linux-3.12.old/fs/exec.c 2013-11-26 08:53:12.175811856 +0000
+++ linux-3.12/fs/exec.c 2013-11-27 09:36:56.231972168 +0000
@@ -1090,8 +1090,8 @@ int flush_old_exec(struct linux_binprm *
bprm->mm = NULL; /* We're using it now */
set_fs(USER_DS);
- current->flags &=
- ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD | PF_NOFREEZE);
+ current->flags &= ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD |
+ PF_NOFREEZE | PF_NO_SETAFFINITY);
flush_thread();
current->personality &= ~bprm->per_clear;
next reply other threads:[~2013-11-29 9:20 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-29 9:19 zhang.yi20 [this message]
-- strict thread matches above, loose matches on Subject: below --
2013-11-14 1:51 kmod: avoid propagating PF_NO_SETAFFINITY into userspace child zhang.yi20
2013-11-14 5:23 ` Tejun Heo
2013-11-14 11:40 ` Oleg Nesterov
2013-11-14 11:55 ` [PATCH 0/1]: (Was: kmod: avoid propagating PF_NO_SETAFFINITY into userspace child) Oleg Nesterov
2013-11-14 11:56 ` [PATCH 1/1] workqueue: swap set_cpus_allowed_ptr() and PF_NO_SETAFFINITY Oleg Nesterov
2013-11-22 23:13 ` Tejun Heo
[not found] ` <OF36E72FA9.51146BE3-ON48257C2E.0008BC6D-48257C2E.0008FF9C@zte.com.cn>
2013-11-25 12:14 ` 答复: " Oleg Nesterov
2013-11-26 2:10 ` [PATCH]: exec: avoid propagating PF_NO_SETAFFINITY into userspace child zhang.yi20
2013-11-26 18:04 ` Oleg Nesterov
2013-11-27 2:07 ` zhang.yi20
2013-11-27 13:20 ` Oleg Nesterov
2013-11-27 18:31 ` Tejun Heo
2013-11-28 9:13 ` Peter Zijlstra
2013-11-28 11:45 ` Oleg Nesterov
2013-11-28 12:17 ` Peter Zijlstra
2013-11-28 13:31 ` Oleg Nesterov
2013-11-28 13:39 ` Peter Zijlstra
2013-11-28 14:13 ` Tejun Heo
2013-11-28 14:31 ` Peter Zijlstra
2013-11-28 14:38 ` Tejun Heo
2013-11-28 14:47 ` Peter Zijlstra
2013-11-28 14:51 ` Tejun Heo
2013-11-28 14:55 ` Peter Zijlstra
2013-11-28 14:57 ` Tejun Heo
2013-11-28 14:59 ` Peter Zijlstra
2013-11-28 15:07 ` Tejun Heo
2013-11-28 15:17 ` Peter Zijlstra
2013-11-28 15:39 ` Tejun Heo
2013-11-28 16:33 ` Peter Zijlstra
2013-11-29 14:33 ` Tejun Heo
2013-11-28 15:47 ` Oleg Nesterov
2013-11-28 16:07 ` Oleg Nesterov
2013-11-28 14:43 ` Peter Zijlstra
2013-11-28 14:53 ` Tejun Heo
2013-11-28 14:57 ` Peter Zijlstra
2013-11-28 15:02 ` Tejun Heo
2013-11-28 15:07 ` Peter Zijlstra
2013-11-28 15:10 ` Tejun Heo
2013-11-28 15:18 ` Peter Zijlstra
2013-11-28 14:38 ` Peter Zijlstra
2013-11-28 14:45 ` Tejun Heo
2013-11-28 14:53 ` Peter Zijlstra
2013-11-28 15:34 ` Oleg Nesterov
2013-11-28 15:40 ` Peter Zijlstra
2013-11-28 16:20 ` Oleg Nesterov
2013-11-28 16:38 ` Peter Zijlstra
2013-11-28 18:13 ` Oleg Nesterov
2013-11-28 14:23 ` Oleg Nesterov
2013-11-28 14:31 ` Tejun Heo
2013-11-28 15:00 ` Oleg Nesterov
2013-11-28 15:02 ` Peter Zijlstra
2013-11-28 13:41 ` Peter Zijlstra
2013-11-28 14:05 ` Tejun Heo
2013-11-28 14:34 ` Oleg Nesterov
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