Hello Sascha, On 6/13/25 09:58, Sascha Hauer wrote: > So far we mapped all RAM as read write with execute permission. This > series series hardens this a bit. The barebox text segment will be > mapped readonly with execute permission, the RO data section as readonly > without execute permission and the remaining RAM will lose its execute > permission.
Very nice. Thanks for working on this. > I tested this series on ARMv7 and ARMv8. I am not confident though that > there are no regressions, so this new behaviour is behind a Kconfig > option. It is default-y, but can be disabled for debugging purposses. > Once this series has proven stable it can be removed. > > I haven't tested it on ARMv4-v6 due to the lack of hardware. I tried on > Qemu, but the write protection did not work as expected. This should be > resolved before merging. I will give it a try and see what I find. Cheers, Ahmad > > Signed-off-by: Sascha Hauer <s.ha...@pengutronix.de> > --- > Sascha Hauer (7): > memory: request RO data section as separate region > ARM: pass barebox base to mmu_early_enable() > ARM: mmu: move ARCH_MAP_WRITECOMBINE to header > ARM: MMU: map memory for barebox proper pagewise > ARM: MMU: map text segment ro and data segments execute never > ARM: MMU64: map memory for barebox proper pagewise > ARM: MMU64: map text segment ro and data segments execute never > > arch/arm/Kconfig | 12 +++++ > arch/arm/cpu/mmu-common.h | 4 ++ > arch/arm/cpu/mmu_32.c | 86 +++++++++++++++++++++++++++------ > arch/arm/cpu/mmu_64.c | 101 > +++++++++++++++++++++++++++++++++++---- > arch/arm/cpu/uncompress.c | 9 ++-- > arch/arm/include/asm/mmu.h | 2 +- > arch/arm/include/asm/pgtable64.h | 1 + > arch/arm/lib32/barebox.lds.S | 3 +- > arch/arm/lib64/barebox.lds.S | 5 +- > common/memory.c | 6 ++- > include/mmu.h | 1 + > 11 files changed, 198 insertions(+), 32 deletions(-) > --- > base-commit: 340e930140e76827cf5cac731e6afe2836e28242 > change-id: 20250613-arm-mmu-xn-ro-1a1d996496ae > > Best regards, -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
