On Tue, Aug 2, 2016 at 2:50 AM, Mark Rutland <[email protected]> wrote: > On Mon, Aug 01, 2016 at 02:25:48PM -0700, Kees Cook wrote: >> On Fri, Jul 29, 2016 at 2:37 AM, Mark Rutland <[email protected]> wrote: >> > Hi, >> > >> > On Thu, Jul 28, 2016 at 07:30:39PM -0700, Kees Cook wrote: >> >> The targets for lkdtm's objcopy were missing which caused them to always >> >> be rebuilt. This corrects the problem. >> >> >> >> Additionally, commit f8fa70f392fa ("arm64: localise Image objcopy flags") >> >> has landed now, so this removes the work-around for the global OBJCOPY >> >> flag setting. >> >> >> >> Reported-by: Linus Torvalds <[email protected]> >> >> Signed-off-by: Kees Cook <[email protected]> >> > >> > With this applied, LKDTM builds fine for me on arm64, the redundant >> > rebuilds are gone, and the result appears to work. So FWIW: >> > >> > Tested-by: Mark Rutland <[email protected]> >> >> Argh, it looks like ARM suffers the same global OBJCOPY problem, so >> I'm going to leave that change out. :( > > :( > > FWIW, I dropped a patch for ARM [1] in Russell's patch system [2]. Hopefully > that will be picked up during the v4.9 merge window. > > Looking again, it appears a number of other arches might be affected: > > [mark@leverpostej:~/src/linux]% git grep 'OBJCOPYFLAGS\s\+:=' -- > arch/*/Makefile > arch/arm/Makefile:OBJCOPYFLAGS :=-O binary -R .comment -S > arch/blackfin/Makefile:OBJCOPYFLAGS := -O binary -R .note -R .comment -S > arch/cris/Makefile:OBJCOPYFLAGS := -O binary -R .note -R .comment -S > arch/ia64/Makefile:OBJCOPYFLAGS := --strip-all > arch/m32r/Makefile:OBJCOPYFLAGS := -O binary -R .note -R .comment -S > arch/metag/Makefile:OBJCOPYFLAGS := -O binary > -R .note -R .comment -S > arch/mn10300/Makefile:OBJCOPYFLAGS := -O binary -R .note -R .comment -R > .GCC-command-line -R .note.gnu.build-id -S > arch/openrisc/Makefile:OBJCOPYFLAGS := -O binary -R .note -R .comment -S > arch/s390/Makefile:OBJCOPYFLAGS := -O binary > arch/sh/Makefile:OBJCOPYFLAGS := -O binary -R .note -R .note.gnu.build-id > -R .comment \ > arch/unicore32/Makefile:OBJCOPYFLAGS := -O binary -R .note -R > .note.gnu.build-id -R .comment -S > > ... so we probably need to fix up these first, regardless.
Oof, yeah. I'll add this to the "weird little things to fix" TODO list. :) > > In the mean time, can we add the targets dependency, but leave the flags > work-around intact? Yeah, done. I've sent a pull request to Greg for that now. -Kees > > Thanks, > Mark. > > [1] > http://lists.infradead.org/pipermail/linux-arm-kernel/2016-July/442974.html > [2] http://www.armlinux.org.uk/developer/patches/viewpatch.php?id=8588/1 -- Kees Cook Chrome OS & Brillo Security
