pid: pid_ns_ctl_handler: remove useless comment

commit 95846ecf9dac("pid: replace pid bitmap implementation with IDR API")
removes 'last_pid' element, and use the idr_get_cursor-idr_set_cursor pair
to set the value of idr, so useless comments should be removed.

Link: https://lkml.kernel.org/r/tencent_157A2A1CAF19A3F5885F0687426159A19708@qq.com
Signed-off-by: Rong Tao <rongtao@cestc.cn>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Jeff Xu <jeffxu@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index 619972c78774f7d2e0ae2ad6fe5aa930ffde9d06..3028b2218aa4485f0aae1c00826f44e952116776 100644 (file)
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -286,12 +286,6 @@ static int pid_ns_ctl_handler(struct ctl_table *table, int write,
        if (write && !checkpoint_restore_ns_capable(pid_ns->user_ns))
                return -EPERM;
 
-       /*
-        * Writing directly to ns' last_pid field is OK, since this field
-        * is volatile in a living namespace anyway and a code writing to
-        * it should synchronize its usage with external means.
-        */
-
        next = idr_get_cursor(&pid_ns->idr) - 1;
 
        tmp.data = &next;