Messages in this thread | | | Date | Tue, 31 Jul 2012 11:11:40 -0700 | From | "H. Peter Anvin" <> | Subject | Re: [tip:perf/core] perf/x86: Fix USER/KERNEL tagging of samples |
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On 07/10/2012 02:48 AM, Ingo Molnar wrote: > > We could read out the current GDT [the SGDT instruction] instead > of looking at gdt_page. > > Then we'd have to decode that descriptor, the limit. Decide > whether the selector points to the GDT or LDT. All the fun x86 > legacies that we mostly forgot already after two decades of > running the kernel in flat linear mode... >
In 32-bit mode there are actually instructions that do that work for you.
-hpa
-- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.
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