Messages in this thread | | | Date | Thu, 22 May 2008 19:49:18 -0700 | From | "H. Peter Anvin" <> | Subject | Re: [RFC] x86: xsave/xrstor support, ucontext_t extensions |
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Roland McGrath wrote: >> hmm.. so the kernel needs to export all the cpuid info (that the kernel >> enables and supports) to the user through some mechanism then? > > For a cheap interface, we use AT_HWCAP for this. Unfortunately that only > covers the first 32 bits of CPUID info. (For another cheap interface, > giving all the CPUID bits in the vDSO would be easy.) > > For a clunky interface that already exists and is "simple" to use, > there is /dev/cpu/0/cpuid now. I wonder if having a device node and > opening it too much for applications that consider the vDSO too complex.
I doubt it.
-hpa
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