As promised, here are the proposed new Memory Protection Keys interfaces. These interfaces make it possible to do something with pkeys other than execute-only support. There are 5 syscalls here. I'm hoping for reviews of this set which can help nail down what the final interfaces will be. You can find a high-level overview of the feature and the new syscalls here: https://www.sr71.net/~dave/intel/pkeys.txt =============================================================== To use memory protection keys (pkeys), an application absolutely needs to be able to set the pkey field in the PTE (obviously has to be done in-kernel) and make changes to the "rights" register (using unprivileged instructions). An application also needs to have an an allocator for the keys themselves. If two different parts of an application both want to protect their data with pkeys, they first need to know which key to use for their individual purposes. This set introduces 5 system calls, in 3 logical groups: 1. PTE pkey setting (sys_pkey_mprotect(), patches #1-3) 2. Key allocation (sys_pkey_alloc() / sys_pkey_free(), patch #4) 3. Rights register manipulation (sys_pkey_set/get(), patch #5) These patches build on top of "core" support already in the tip tree, specifically 62b5f7d013, which can currently be found at: http://git.kernel.org/cgit/linux/kernel/git/tip/tip.git/log/?h=mm/pkeys I have manpages written for some of these syscalls, and I will submit a full set of manpages once we've reached some consensus on what the interfaces should be. This set is also available here: git://git.kernel.org/pub/scm/linux/kernel/git/daveh/x86-pkeys.git pkeys-v024 I've written a set of unit tests for these interfaces, which is available here: https://www.sr71.net/~dave/intel/pkeys-test-2016-02-22/ I will submit that code for inclusion with the final version of these patches. === diffstat === Dave Hansen (7): x86, pkeys: Documentation mm: implement new pkey_mprotect() system call x86, pkeys: make mprotect_key() mask off additional vm_flags x86: wire up mprotect_key() system call x86, pkeys: allocation/free syscalls x86, pkeys: add pkey set/get syscalls pkeys: add details of system call use to Documentation/ Documentation/x86/protection-keys.txt | 91 +++++++++++++++++ arch/x86/entry/syscalls/syscall_32.tbl | 5 + arch/x86/entry/syscalls/syscall_64.tbl | 5 + arch/x86/include/asm/mmu.h | 8 ++ arch/x86/include/asm/mmu_context.h | 25 +++-- arch/x86/include/asm/pkeys.h | 83 ++++++++++++++- arch/x86/kernel/fpu/xstate.c | 73 +++++++++++++- arch/x86/mm/pkeys.c | 40 ++++++-- include/linux/pkeys.h | 39 ++++++-- include/uapi/asm-generic/mman-common.h | 5 + mm/mprotect.c | 133 ++++++++++++++++++++++++- 11 files changed, 476 insertions(+), 31 deletions(-) Cc: linux-api@xxxxxxxxxxxxxxx Cc: linux-mm@xxxxxxxxx Cc: x86@xxxxxxxxxx Cc: torvalds@xxxxxxxxxxxxxxxxxxxx Cc: akpm@xxxxxxxxxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
