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 --- arch/sh64/mm/fault.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/sh64/mm/fault.c') diff --git a/arch/sh64/mm/fault.c b/arch/sh64/mm/fault.c index dd81c669c79..7aea586fc3d 100644 --- a/arch/sh64/mm/fault.c +++ b/arch/sh64/mm/fault.c @@ -278,7 +278,7 @@ bad_area: show_regs(regs); #endif } - if (is_init(tsk)) { + if (is_global_init(tsk)) { panic("INIT had user mode bad_area\n"); } tsk->thread.address = address; @@ -320,14 +320,14 @@ no_context: * us unable to handle the page fault gracefully. */ out_of_memory: - if (is_init(current)) { + if (is_global_init(current)) { panic("INIT out of memory\n"); yield(); goto survive; } printk("fault:Out of memory\n"); up_read(&mm->mmap_sem); - if (is_init(current)) { + if (is_global_init(current)) { yield(); down_read(&mm->mmap_sem); goto survive; -- cgit v1.2.3-70-g09d2