| Date | Thu, 2 Nov 2017 19:01:07 +0000 | From | Will Deacon <> | Subject | Re: [PATCH 00/23] KAISER: unmap most of the kernel from userspace page tables |
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Hi Dave,
[+linux-arm-kernel]
On Tue, Oct 31, 2017 at 03:31:46PM -0700, Dave Hansen wrote: > KAISER makes it harder to defeat KASLR, but makes syscalls and > interrupts slower. These patches are based on work from a team at > Graz University of Technology posted here[1]. The major addition is > support for Intel PCIDs which builds on top of Andy Lutomorski's PCID > work merged for 4.14. PCIDs make KAISER's overhead very reasonable > for a wide variety of use cases.
I just wanted to say that I've got a version of this up and running for arm64. I'm still ironing out a few small details, but I hope to post it after the merge window. We always use ASIDs, and the perf impact looks like it aligns roughly with your findings for a PCID-enabled x86 system.
Cheers,
Will
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