Messages in this thread | | | Date | Sat, 13 Nov 2021 20:24:11 -0800 | Subject | Re: [PATCH 3/3] x86_64: Use relative per-cpu offsets | From | "H. Peter Anvin" <> |
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On 11/13/21 17:18, Andy Lutomirski wrote: > > > On Sat, Nov 13, 2021, at 4:40 AM, Brian Gerst wrote: >> The per-cpu section is currently linked at virtual address 0, because >> older compilers hardcoded the stack protector canary value at a fixed >> offset from the start of the GS segment. Use a standard relative offset >> as the GS base when the stack protector is disabled, or a newer compiler >> is used that supports a configurable location for the stack canary. > > Can you explain the benefit? Also, I think we should consider dropping support for the fixed model like we did on x86_32. >
It would seem that UNLESS the fixed model is dropped, the benefit is probably negative.
-hpa
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