From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga09.intel.com ([134.134.136.24]) by linuxtogo.org with esmtp (Exim 4.72) (envelope-from ) id 1Sff5f-0007hK-HO for openembedded-core@lists.openembedded.org; Sat, 16 Jun 2012 00:34:03 +0200 Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga102.jf.intel.com with ESMTP; 15 Jun 2012 15:23:23 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.67,351,1309762800"; d="scan'208";a="158239861" Received: from unknown (HELO envy.home) ([10.255.12.88]) by orsmga002.jf.intel.com with ESMTP; 15 Jun 2012 15:23:23 -0700 Message-ID: <4FDBB58C.5030208@linux.intel.com> Date: Fri, 15 Jun 2012 15:22:04 -0700 From: Darren Hart User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:13.0) Gecko/20120605 Thunderbird/13.0 MIME-Version: 1.0 To: Patches and discussions about the oe-core layer References: <3b44305edae36265295087fb5f31d22d660599b8.1339650859.git.dvhart@linux.intel.com> <4FD98D3B.7060200@gmail.com> In-Reply-To: <4FD98D3B.7060200@gmail.com> X-Enigmail-Version: 1.4.2 Subject: Re: [PATCH 2/3] busybox: Add setsid and cttyhack for tiny DISTRO_FEATURE X-BeenThere: openembedded-core@lists.openembedded.org X-Mailman-Version: 2.1.11 Precedence: list Reply-To: Patches and discussions about the oe-core layer List-Id: Patches and discussions about the oe-core layer List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 15 Jun 2012 22:34:03 -0000 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 06/14/2012 12:05 AM, Khem Raj wrote: > On 6/13/2012 10:19 PM, Darren Hart wrote: >> When building very small systems, it can be useful to spawn a >> shell from a simple init script, rather than a full System V Init >> process. This requires the shell be the session leader and be >> able to open the controlling terminal if it is to have job >> control. > >> Enable CONFIG_CTTYHACK and CONFIG_SETSID to enable this for >> distros defining the "tiny" DISTRO_FEATURE. > >> Signed-off-by: Darren Hart CC: OE Core >> --- >> meta/recipes-core/busybox/busybox.inc | 2 ++ 1 files changed, >> 2 insertions(+), 0 deletions(-) > >> diff --git a/meta/recipes-core/busybox/busybox.inc >> b/meta/recipes-core/busybox/busybox.inc index 5b83d32..d07ba7e >> 100644 --- a/meta/recipes-core/busybox/busybox.inc +++ >> b/meta/recipes-core/busybox/busybox.inc @@ -57,6 +57,8 @@ def >> features_to_busybox_settings(d): busybox_cfg('nls', >> distro_features, 'CONFIG_LOCALE_SUPPORT', cnf, rem) >> busybox_cfg('ipv4', distro_features, >> 'CONFIG_FEATURE_IFUPDOWN_IPV4', cnf, rem) busybox_cfg('ipv6', >> distro_features, 'CONFIG_FEATURE_IFUPDOWN_IPV6', cnf, rem) + >> busybox_cfg('tiny', distro_features, 'CONFIG_SETSID', cnf, rem) >> + busybox_cfg('tiny', distro_features, 'CONFIG_CTTYHACK', cnf, >> rem) return "\n".join(cnf), "\n".join(rem) > >> # X, Y = ${@features_to_uclibc_settings(d)} > > Enabling cttyhack and setsid could be a good thing in general > (thinking of initramfs kind of images) so I would propose to enable > it by default and not introduce another distro knob here. How much > does busybox code size grow which these two features turned on.? So this struck me as strange, but I did it twice to make sure I didn't mess something up: BEFORE - -rwxr-xr-x 1 dvhart dvhart 2799417 2012-06-15 15:06 busybox - -rwxr-xr-x 1 dvhart dvhart 547872 2012-06-15 15:06 busybox_stripped AFTER (w/ SETSID and CTTYHACK) - -rwxr-xr-x 1 dvhart dvhart 2805195 2012-06-15 14:45 busybox - -rwxr-xr-x 1 dvhart dvhart 547872 2012-06-15 15:05 busybox_stripped DELTA busybox: 5778 busybox_stripped: 0 The difference is <6k for the unstripped binary, and 0 bytes for the stripped binary. It must have something to do with the way busybox builds and enables features. The above was using my host strip command. I also tried building the rootfs with and without these features and comparing the cross-stripped binaries in the rootfs, delta is also 0 bytes. So the cost is "negligible" and there is a clear advantage to having these two options enabled. I'll resend with a two line change to the defconfig to enable them. - -- Darren > > otherwise second best thing is to keep it in poky-tiny distro > layer which wants to set the policy > > _______________________________________________ Openembedded-core > mailing list Openembedded-core@lists.openembedded.org > http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/openembedded-core > > - -- Darren Hart Intel Open Source Technology Center Yocto Project - Linux Kernel -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQEcBAEBAgAGBQJP27WMAAoJEKbMaAwKp364Hf0IAKpHOMWy63ZPYwN+Ay7wXPf1 KaUe4fWGBIMNJqS5FGJyhxBnWMdXJceAKMP6Wo2nIa/kvjat//IME8v41xwAb+mD 5sjZpkcBE02CFq9rZmHfiTTPbYC7iS8a6Dz5n/fTLb79b189Jv3Rx/G3GCN4ioeC xqwVU8zmdtkrHfU+UonR5G4HdNMCjOCFETLWcWW6DNTsj5PmazJV2cMIZTYJEr43 G/EyvO2fz/n+y53dsI04zwNEXuyr0pjurCK7dXt9oxlOnDvE276yS1b0Xihwm3cW G/h0udSeQ3fcF91vCxdYMAlQNJyMqiCOCeSW5gOVe6NKs+kuxzRqYFSEfD0gtmY= =aZeL -----END PGP SIGNATURE-----