Hi Nicolas, On 18/07/16 13:31, Nicolas Pitre wrote: > This series provides the necessary changes to allow "flat" executable > binaries meant for no-MMU systems to actually run on systems with a MMU. > > This can also be found in the following git repo: > > git://git.linaro.org/people/nicolas.pitre/linux binfmt_flat_with_mmu > > *Why?* > > Because developing and testing natively on a large system with lots of > RAM makes it so much more convenient to use all the existing profiling > tools and debugging facilities that a kernel with lots of RAM can give. > And incidentally, those systems with lots of RAM all have a MMU. > > *Why not use elf_fdpic?* > > The flat executable format is simple with very small footprint > overhead, either in the executables themselves or kernel support. > This makes the flat format more suitable than elf_fdpic for very small > single-user-app embedded systems. > > And while elf_fdpic binaries can run on MMU systems, flat binaries still > couldn't, which just felt wrong. > > So here it is. The no-MMU support should remain unaffected. Please consider > for pulling. > > Tested on ARM only with a busybox build.
Tested on m68k (ColdFire specifically) and everything compiles cleanly and works as before. I tried running a flat binary on an MMU ColdFire system and that crashed out with a SIGSEGV. I haven't debugged any further than that yet. I had a look over the patches and I didn't see any specific problems. So from me: Reviewed-by: Greg Ungerer <g...@linux-m68k.org> When I get a minute I'll dig a little into that bflat running on MMU problem on ColdFire. Regards Greg > Changes since v1: > > - Removed SuperH and Xtensa from the Kconfig rule as they fail to build > due to lack of get/put_unaligned_user(). > > - Clarified some commit logs a bit. > > diffstat: > > arch/arm/include/asm/flat.h | 5 +- > arch/m68k/include/asm/flat.h | 5 +- > fs/Kconfig.binfmt | 3 +- > fs/binfmt_elf_fdpic.c | 38 +--- > fs/binfmt_flat.c | 372 +++++++++++++++++++++-------------- > fs/exec.c | 33 ++++ > include/linux/binfmts.h | 2 + > 7 files changed, 268 insertions(+), 190 deletions(-) > >
