arm, kbuild: make "make install" not depend on vmlinux

Install targets (install, zinstall, uinstall) on arm have a dependency
to vmlinux. This may cause parts of the kernel to be rebuilt during
installation. We must avoid this since this may run as root. Install
targets "ABSOLUTELY MUST NOT MODIFY THE SOURCE TREE." as Linus
emphasized this in:

 http://lkml.org/lkml/2013/7/10/600

So on arm and maybe other archs we need the same as for x86:

 1648e4f8 x86, kbuild: make "make install" not depend on vmlinux

This patch fixes this for arm. Dependencies are removed and instead a
check to install.sh is added for the files that are needed.

This issue was uncovered by this build error where the -j option is
used in conjunction with install targets:

 $ make <makeflags>
 $ make <makeflags> zinstall
 ...
   DEPMOD
 Usage: .../scripts/depmod.sh /sbin/depmod <kernelrelease>

(INSTALL_MOD_PATH and INSTALL_PATH variables set, so no root perms
required in this case.)

The problem is that zinstall on arm due to its dependency to vmlinux
does a prepare/prepare3 and finally does a forced rewrite of
kernel.release even if it exists already.

Rebuilding kernel.release removes it first and then recreates it. This
might race with another parallel make job running depmod.

So this patch should fix this one too.

Also quoting $(KERNELRELEASE) arg for install.sh as this messes
argument order in case it is empty (which is the case if the kernel
was not built yet).

Signed-off-by: Robert Richter <robert.richter@linaro.org>
Signed-off-by: Robert Richter <rric@kernel.org>
Acked-by: Michal Marek <mmarek@suse.cz>.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Michal Marek <mmarek@suse.cz>

diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index a37a50f575a27af2c95abca5c473d6a60233d8b9..db50b626be9871f7426ee394a9b189d8d504c8a3 100644 (file)
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -296,10 +296,15 @@ archprepare:
 # Convert bzImage to zImage
 bzImage: zImage
 
-zImage Image xipImage bootpImage uImage: vmlinux
+BOOT_TARGETS   = zImage Image xipImage bootpImage uImage
+INSTALL_TARGETS        = zinstall uinstall install
+
+PHONY += bzImage $(BOOT_TARGETS) $(INSTALL_TARGETS)
+
+$(BOOT_TARGETS): vmlinux
        $(Q)$(MAKE) $(build)=$(boot) MACHINE=$(MACHINE) $(boot)/$@
 
-zinstall uinstall install: vmlinux
+$(INSTALL_TARGETS):
        $(Q)$(MAKE) $(build)=$(boot) MACHINE=$(MACHINE) $@
 
 %.dtb: | scripts

diff --git a/arch/arm/boot/Makefile b/arch/arm/boot/Makefile
index 84aa2caf07ed203fb810220258401a1b51f7cab3..ec2f8065f955c5c31a69888bf261c58ea56ffb6d 100644 (file)
--- a/arch/arm/boot/Makefile
+++ b/arch/arm/boot/Makefile
@@ -95,24 +95,24 @@ initrd:
        @test "$(INITRD)" != "" || \
        (echo You must specify INITRD; exit -1)
 
-install: $(obj)/Image
-       $(CONFIG_SHELL) $(srctree)/$(src)/install.sh $(KERNELRELEASE) \
+install:
+       $(CONFIG_SHELL) $(srctree)/$(src)/install.sh "$(KERNELRELEASE)" \
        $(obj)/Image System.map "$(INSTALL_PATH)"
 
-zinstall: $(obj)/zImage
-       $(CONFIG_SHELL) $(srctree)/$(src)/install.sh $(KERNELRELEASE) \
+zinstall:
+       $(CONFIG_SHELL) $(srctree)/$(src)/install.sh "$(KERNELRELEASE)" \
        $(obj)/zImage System.map "$(INSTALL_PATH)"
 
-uinstall: $(obj)/uImage
-       $(CONFIG_SHELL) $(srctree)/$(src)/install.sh $(KERNELRELEASE) \
+uinstall:
+       $(CONFIG_SHELL) $(srctree)/$(src)/install.sh "$(KERNELRELEASE)" \
        $(obj)/uImage System.map "$(INSTALL_PATH)"
 
 zi:
-       $(CONFIG_SHELL) $(srctree)/$(src)/install.sh $(KERNELRELEASE) \
+       $(CONFIG_SHELL) $(srctree)/$(src)/install.sh "$(KERNELRELEASE)" \
        $(obj)/zImage System.map "$(INSTALL_PATH)"
 
 i:
-       $(CONFIG_SHELL) $(srctree)/$(src)/install.sh $(KERNELRELEASE) \
+       $(CONFIG_SHELL) $(srctree)/$(src)/install.sh "$(KERNELRELEASE)" \
        $(obj)/Image System.map "$(INSTALL_PATH)"
 
 subdir-            := bootp compressed dts

diff --git a/arch/arm/boot/install.sh b/arch/arm/boot/install.sh
index 06ea7d42ce8e6bb9f72633a14abd2ace113fa712..2a45092a40e3251e44447f3349e80ee0a69e97a4 100644 (file)
--- a/arch/arm/boot/install.sh
+++ b/arch/arm/boot/install.sh
@@ -20,6 +20,20 @@
 #   $4 - default install path (blank if root directory)
 #
 
+verify () {
+       if [ ! -f "$1" ]; then
+               echo ""                                                   1>&2
+               echo " *** Missing file: $1"                              1>&2
+               echo ' *** You need to run "make" before "make install".' 1>&2
+               echo ""                                                   1>&2
+               exit 1
+       fi
+}
+
+# Make sure the files actually exist
+verify "$2"
+verify "$3"
+
 # User may have a custom install script
 if [ -x ~/bin/${INSTALLKERNEL} ]; then exec ~/bin/${INSTALLKERNEL} "$@"; fi
 if [ -x /sbin/${INSTALLKERNEL} ]; then exec /sbin/${INSTALLKERNEL} "$@"; fi