+ pid-pid_ns_ctl_handler-remove-useless-comment.patch added to mm-nonmm-unstable branch

+ pid-pid_ns_ctl_handler-remove-useless-comment.patch added to mm-nonmm-unstable branch

[Andrew Morton]

The patch titled
     Subject: pid: pid_ns_ctl_handler: remove useless comment
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     pid-pid_ns_ctl_handler-remove-useless-comment.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/pid-pid_ns_ctl_handler-remove-useless-comment.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days

------------------------------------------------------
From: Rong Tao <rongtao@cestc.cn>
Subject: pid: pid_ns_ctl_handler: remove useless comment
Date: Mon, 11 Sep 2023 22:55:09 +0800

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>
---

 kernel/pid_namespace.c |    6 ------
 1 file changed, 6 deletions(-)

--- a/kernel/pid_namespace.c~pid-pid_ns_ctl_handler-remove-useless-comment
+++ a/kernel/pid_namespace.c
@@ -286,12 +286,6 @@ static int pid_ns_ctl_handler(struct ctl
 	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;
_

Patches currently in -mm which might be from rongtao@cestc.cn are

pid-pid_ns_ctl_handler-remove-useless-comment.patch