Memory protection keys enable applications to protect its
address space from inadvertent access or corruption from
itself.
The overall idea:
A process allocates a key and associates it with
a address range within its address space.
The process than can dynamically set read/write
permissions on the key without involving the
kernel. Any code that violates the permissions
off the address space; as defined by its associated
key, will receive a segmentation fault.
This patch series enables the feature on PPC64.
It is enabled on HPTE 64K-page platform.
ISA3.0 section 5.7.13 describes the detailed specifications.
Testing:
This patch series has passed all the protection key
tests available in the selftests directory. Though
the test are written for x86, I have updated the
tests to cater to powerpc. Will send the patch
separately, along with documentation updates.
Thanks-to: Dave Hansen, Aneesh, Paul Mackerras,
Michael Ellermen :)
Ram Pai (7):
Free up four PTE bits to accommadate memory keys
Implement sys_pkey_alloc and sys_pkey_free system call.
store and restore the key state across context switches.
Implementation for sys_mprotect_pkey() system call.
Program HPTE key protection bits.
Handle exceptions caused by violation of key protection.
Deliver SEGV signal on protection key violation.
arch/powerpc/Kconfig | 15 ++
arch/powerpc/include/asm/book3s/64/hash-4k.h | 12 ++
arch/powerpc/include/asm/book3s/64/hash-64k.h | 38 ++--
arch/powerpc/include/asm/book3s/64/hash.h | 8 +-
arch/powerpc/include/asm/book3s/64/mmu-hash.h | 10 +
arch/powerpc/include/asm/book3s/64/mmu.h | 10 +
arch/powerpc/include/asm/book3s/64/pgtable.h | 84 +++++++-
arch/powerpc/include/asm/mman.h | 29 +--
arch/powerpc/include/asm/mmu_context.h | 12 ++
arch/powerpc/include/asm/pkeys.h | 159 +++++++++++++++
arch/powerpc/include/asm/processor.h | 5 +
arch/powerpc/include/asm/reg.h | 10 +-
arch/powerpc/include/asm/systbl.h | 3 +
arch/powerpc/include/asm/unistd.h | 6 +-
arch/powerpc/include/uapi/asm/ptrace.h | 5 +-
arch/powerpc/include/uapi/asm/unistd.h | 3 +
arch/powerpc/kernel/asm-offsets.c | 1 +
arch/powerpc/kernel/exceptions-64s.S | 10 +-
arch/powerpc/kernel/process.c | 18 ++
arch/powerpc/kernel/signal_32.c | 18 +-
arch/powerpc/kernel/signal_64.c | 11 ++
arch/powerpc/kernel/traps.c | 49 +++++
arch/powerpc/mm/Makefile | 1 +
arch/powerpc/mm/dump_linuxpagetables.c | 3 +-
arch/powerpc/mm/fault.c | 21 +-
arch/powerpc/mm/hash64_4k.c | 12 +-
arch/powerpc/mm/hash64_64k.c | 73 +++----
arch/powerpc/mm/hash_utils_64.c | 43 ++++-
arch/powerpc/mm/hugetlbpage-hash64.c | 16 +-
arch/powerpc/mm/mmu_context_book3s64.c | 5 +
arch/powerpc/mm/pkeys.c | 267 ++++++++++++++++++++++++++
include/linux/mm.h | 32 +--
include/uapi/asm-generic/mman-common.h | 2 +-
33 files changed, 856 insertions(+), 135 deletions(-)
create mode 100644 arch/powerpc/include/asm/pkeys.h
create mode 100644 arch/powerpc/mm/pkeys.c
--
1.8.3.1
