From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Rapoport Subject: [PATCH RFC] mm: add MAP_EXCLUSIVE to create exclusive user mappings Date: Sun, 27 Oct 2019 12:17:31 +0200 Message-ID: <1572171452-7958-1-git-send-email-rppt@kernel.org> Return-path: Sender: linux-kernel-owner@vger.kernel.org To: linux-kernel@vger.kernel.org Cc: Alexey Dobriyan , Andrew Morton , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Dave Hansen , James Bottomley , Mike Rapoport , Peter Zijlstra , Steven Rostedt , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , linux-api@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org, Mike Rapoport List-Id: linux-api@vger.kernel.org From: Mike Rapoport Hi, The patch below aims to allow applications to create mappins that have pages visible only to the owning process. Such mappings could be used to store secrets so that these secrets are not visible neither to other processes nor to the kernel. I've only tested the basic functionality, the changes should be verified against THP/migration/compaction. Yet, I'd appreciate early feedback. Mike Rapoport (1): mm: add MAP_EXCLUSIVE to create exclusive user mappings arch/x86/mm/fault.c | 14 ++++++++++ fs/proc/task_mmu.c | 1 + include/linux/mm.h | 9 +++++++ include/linux/page-flags.h | 7 +++++ include/linux/page_excl.h | 49 ++++++++++++++++++++++++++++++++++ include/trace/events/mmflags.h | 9 ++++++- include/uapi/asm-generic/mman-common.h | 1 + kernel/fork.c | 3 ++- mm/Kconfig | 3 +++ mm/gup.c | 8 ++++++ mm/memory.c | 3 +++ mm/mmap.c | 16 +++++++++++ mm/page_alloc.c | 5 ++++ 13 files changed, 126 insertions(+), 2 deletions(-) create mode 100644 include/linux/page_excl.h -- 2.7.4