Hi, On 03/20/2015 11:53 AM, Laurent Dufour wrote: > CRIU is recreating the process memory layout by remapping the checkpointee > memory area on top of the current process (criu). This includes remapping > the vDSO to the place it has at checkpoint time. > > However some architectures like powerpc are keeping a reference to the vDSO > base address to build the signal return stack frame by calling the vDSO > sigreturn service. So once the vDSO has been moved, this reference is no > more valid and the signal frame built later are not usable. > > This patch serie is introducing a new mm hook 'arch_remap' which is called > when mremap is done and the mm lock still hold. The next patch is adding the > vDSO remap and unmap tracking to the powerpc architecture. > > Laurent Dufour (2): > mm: Introducing arch_remap hook > powerpc/mm: Tracking vDSO remap > > arch/powerpc/include/asm/mmu_context.h | 35 +++++++++++++++++++++++++++++++- > arch/s390/include/asm/mmu_context.h | 6 ++++++ > arch/um/include/asm/mmu_context.h | 5 +++++ > arch/unicore32/include/asm/mmu_context.h | 6 ++++++ > arch/x86/include/asm/mmu_context.h | 6 ++++++ > include/asm-generic/mm_hooks.h | 6 ++++++ > mm/mremap.c | 9 ++++++-- > 7 files changed, 70 insertions(+), 3 deletions(-) We would like to be able to remap/unmap the VDSO on arm and arm64 as well. When I proposed a patch with mmu_context.h and mmu-arch-hooks.h changes to arm64 that were nearly identical to those done to powerpc, Will Deacon reasonably suggested [1] attempting to combine the code and provide generic VDSO accessors. Unfortunately, I no prior experience with generic MM code. Can anyone advise on how to get started with that? 1. http://www.spinics.net/lists/linux-arm-msm/msg18441.html Thanks, Christopher Covington -- Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
