From b460cbc581a53cc088ceba80608021dd49c63c43 Mon Sep 17 00:00:00 2001 From: "Serge E. Hallyn" Date: Thu, 18 Oct 2007 23:39:52 -0700 Subject: pid namespaces: define is_global_init() and is_container_init() is_init() is an ambiguous name for the pid==1 check. Split it into is_global_init() and is_container_init(). A cgroup init has it's tsk->pid == 1. A global init also has it's tsk->pid == 1 and it's active pid namespace is the init_pid_ns. But rather than check the active pid namespace, compare the task structure with 'init_pid_ns.child_reaper', which is initialized during boot to the /sbin/init process and never changes. Changelog: 2.6.22-rc4-mm2-pidns1: - Use 'init_pid_ns.child_reaper' to determine if a given task is the global init (/sbin/init) process. This would improve performance and remove dependence on the task_pid(). 2.6.21-mm2-pidns2: - [Sukadev Bhattiprolu] Changed is_container_init() calls in {powerpc, ppc,avr32}/traps.c for the _exception() call to is_global_init(). This way, we kill only the cgroup if the cgroup's init has a bug rather than force a kernel panic. [akpm@linux-foundation.org: fix comment] [sukadev@us.ibm.com: Use is_global_init() in arch/m32r/mm/fault.c] [bunk@stusta.de: kernel/pid.c: remove unused exports] [sukadev@us.ibm.com: Fix capability.c to work with threaded init] Signed-off-by: Serge E. Hallyn Signed-off-by: Sukadev Bhattiprolu Acked-by: Pavel Emelianov Cc: Eric W. Biederman Cc: Cedric Le Goater Cc: Dave Hansen Cc: Herbert Poetzel Cc: Kirill Korotaev Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/sysctl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/sysctl.c') diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 067554bda8b7..44868e4df1d3 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1888,7 +1888,7 @@ int proc_dointvec_bset(struct ctl_table *table, int write, struct file *filp, return -EPERM; } - op = is_init(current) ? OP_SET : OP_AND; + op = is_global_init(current) ? OP_SET : OP_AND; return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, do_proc_dointvec_bset_conv,&op); } -- cgit v1.2.3