From 9bd0a077122a6b15069aab7a59c8f50f736fa1dd Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Thu, 31 May 2012 16:26:25 -0700 Subject: um: should hold tasklist_lock while traversing processes Traversing the tasks requires holding tasklist_lock, otherwise it is unsafe. p.s. However, I'm not sure that calling os_kill_ptraced_process() in the atomic context is correct. It seem to work, but please take a closer look. Signed-off-by: Anton Vorontsov Cc: Richard Weinberger Cc: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/kernel/reboot.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'arch') diff --git a/arch/um/kernel/reboot.c b/arch/um/kernel/reboot.c index 4d93dff6b371..66d754c46e7b 100644 --- a/arch/um/kernel/reboot.c +++ b/arch/um/kernel/reboot.c @@ -4,6 +4,7 @@ */ #include "linux/sched.h" +#include "linux/spinlock.h" #include "linux/slab.h" #include "kern_util.h" #include "os.h" @@ -22,6 +23,7 @@ static void kill_off_processes(void) struct task_struct *p; int pid; + read_lock(&tasklist_lock); for_each_process(p) { if (p->mm == NULL) continue; @@ -29,6 +31,7 @@ static void kill_off_processes(void) pid = p->mm->context.id.u.pid; os_kill_ptraced_process(pid, 1); } + read_unlock(&tasklist_lock); } } -- cgit v1.2.3-59-g8ed1b