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From: Nicolas Pitre <nicolas.pitre@linaro.org>
To: Michal Marek <mmarek@suse.com>, linux-kbuild@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, Al Viro <viro@ZenIV.linux.org.uk>,
	Rusty Russell <rusty@rustcorp.com.au>
Subject: [PATCH v3 7/7] kconfig option for TRIM_UNUSED_KSYMS
Date: Thu, 18 Feb 2016 15:07:03 -0500	[thread overview]
Message-ID: <1455826023-2134-8-git-send-email-nicolas.pitre@linaro.org> (raw)
In-Reply-To: <1455826023-2134-1-git-send-email-nicolas.pitre@linaro.org>

The config option to enable it all.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
---
 init/Kconfig | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/init/Kconfig b/init/Kconfig
index 22320804fb..e6f666331b 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1990,6 +1990,22 @@ config MODULE_COMPRESS_XZ
 
 endchoice
 
+config TRIM_UNUSED_KSYMS
+	bool "Trim unused exported kernel symbols"
+	depends on MODULES && !UNUSED_SYMBOLS
+	help
+	  The kernel and some modules make many symbols available for
+	  other modules to use via EXPORT_SYMBOL() and variants. Depending
+	  on the set of modules being selected in your kernel configuration,
+	  many of those exported symbols might never be used.
+
+	  This option allows for unused exported symbols to be dropped from
+	  the build. In turn, this provides the compiler more opportunities
+	  (especially when using LTO) for optimizing the code and reducing
+	  binary size.  This might have some security advantages as well.
+
+	  If unsure say N.
+
 endif # MODULES
 
 config MODULES_TREE_LOOKUP
-- 
2.5.0

  parent reply	other threads:[~2016-02-18 20:07 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-18 20:06 [PATCH v3 0/7] Trim unused exported kernel symbols Nicolas Pitre
2016-02-18 20:06 ` [PATCH v3 1/7] kbuild: record needed exported symbols for modules Nicolas Pitre
2016-02-18 20:06 ` [PATCH v3 2/7] allow for per-symbol configurable EXPORT_SYMBOL() Nicolas Pitre
2016-02-18 20:06 ` [PATCH v3 3/7] fixdep: accept extra dependencies on stdin Nicolas Pitre
2016-02-18 20:07 ` [PATCH v3 4/7] kbuild: de-duplicate fixdep usage Nicolas Pitre
2016-02-18 20:07 ` [PATCH v3 5/7] kbuild: add fine grained build dependencies for exported symbols Nicolas Pitre
2016-02-18 20:07 ` [PATCH v3 6/7] create/adjust generated/autoksyms.h Nicolas Pitre
2016-02-28 12:11   ` Zev Weiss
2016-02-28 19:31     ` Nicolas Pitre
2016-02-18 20:07 ` Nicolas Pitre [this message]
2016-02-24 15:19 ` [PATCH v3 0/7] Trim unused exported kernel symbols Nicolas Pitre

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