Messages in this thread | | | Subject | Re: [PATCH v2 10/20] x86: avoid W^X being broken during modules loading | From | Nadav Amit <> | Date | Mon, 11 Feb 2019 11:09:25 -0800 |
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> On Feb 11, 2019, at 11:01 AM, Borislav Petkov <bp@alien8.de> wrote: > > On Mon, Feb 11, 2019 at 10:45:26AM -0800, Nadav Amit wrote: >> Are you sure about that? This path is still used when modules are loaded. > > Yes, I'm sure. Loading a module does a gazillion things so saving a > couple of insns - yes, boot_cpu_has() is usually a RIP-relative MOV and a > TEST - doesn't show even as a blip on any radar.
I fully agree, if that is the standard.
It is just that I find the use of static_cpu_has()/boot_cpu_has() to be very inconsistent. I doubt that show_cpuinfo_misc(), copy_fpstate_to_sigframe(), or i915_memcpy_init_early() that use static_cpu_has() are any hotter than text_poke_early().
Anyhow, I’ll use boot_cpu_has() as you said.
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