Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756641Ab3CNKPJ (ORCPT ); Thu, 14 Mar 2013 06:15:09 -0400 Received: from mail-pb0-f43.google.com ([209.85.160.43]:61465 "EHLO mail-pb0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755566Ab3CNKPI (ORCPT ); Thu, 14 Mar 2013 06:15:08 -0400 MIME-Version: 1.0 Reply-To: mtk.manpages@gmail.com In-Reply-To: <87620xccdn.fsf@xmission.com> References: <87620xccdn.fsf@xmission.com> From: "Michael Kerrisk (man-pages)" Date: Thu, 14 Mar 2013 11:14:47 +0100 Message-ID: Subject: Re: Documenting reboot(2) changes for PID namespace in 3.9 To: "Eric W. Biederman" Cc: Li Zefan , linux-man , Linux Containers , lkml Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2601 Lines: 87 On Tue, Mar 12, 2013 at 8:20 AM, Eric W. Biederman wrote: > "Michael Kerrisk (man-pages)" writes: > >> Li, >> >> Regarding your commit 923c7538236564c46ee80c253a416705321f13e3 , I >> plan to apply the following patch to the reboot(2) manual page. Does >> it look okay to you? > > You have documented the behavior as of 3.4. Thanks Eric. I tweaked the version number. > The change in 3.9 is to allow that same behavior in a pid_namespace > created with a user namespace. Aka in 3.9 the permission > check changed from capable(CAP_SYS_BOOT) to ns_capable(pid_ns->user_ns, CAP_SYS_BOOT); Does anything need to be detailed about this in the man page then? Thanks, Michael > > Eric > >> Thanks, >> >> Michael >> >> diff --git a/man2/reboot.2 b/man2/reboot.2 >> index 8347870..1c17b85 100644 >> --- a/man2/reboot.2 >> +++ b/man2/reboot.2 >> @@ -24,7 +24,7 @@ >> .\" Modified, 27 May 2004, Michael Kerrisk >> .\" Added notes on capability requirements >> .\" >> -.TH REBOOT 2 2010-10-31 "Linux" "Linux Programmer's Manual" >> +.TH REBOOT 2 2013-03-12 "Linux" "Linux Programmer's Manual" >> .SH NAME >> reboot \- reboot or enable/disable Ctrl-Alt-Del >> .SH SYNOPSIS >> @@ -147,6 +147,26 @@ For the i386 architecture, the additional >> argument does not do >> anything at present (2.1.122), but the type of reboot can be >> determined by kernel command-line arguments ("reboot=...") to be >> either warm or cold, and either hard or through the BIOS. >> +.SS Behavior inside PID namespaces >> +.\" commit commit 923c7538236564c46ee80c253a416705321f13e3 >> +Since Linux 3.9, when > ^^^ 3.4 >> +.BR reboot () >> +is called from a PID namespace (see >> +.BR pid_namespaces (7)) >> +other than the initial PID namespace, >> +the effect of the call is to send a signal to the namespace "init" process. >> +.BR LINUX_REBOOT_CMD_RESTART >> +and >> +.BR LINUX_REBOOT_CMD_RESTART2 >> +cause a >> +.BR SIGHUP >> +signal to be sent. >> +.BR LINUX_REBOOT_CMD_POWER_OFF >> +and >> +.BR LINUX_REBOOT_CMD_HALT >> +cause a >> +.B SIGINT >> +signal to be sent. >> .SH RETURN VALUE >> For the values of >> .I cmd -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Author of "The Linux Programming Interface"; http://man7.org/tlpi/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/