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Subject: Re: [PATCH v14 09/19] x86/mm: x86/sgx: Signal SEGV_SGXERR for #PFs w/
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From: Dave Hansen <dave.hansen@intel.com>
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Date: Thu, 1 Nov 2018 10:51:50 -0700
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On 10/31/18 3:52 PM, Andy Lutomirski wrote:
> I think EENTER in plain user code should have well defined semantics,
> and it should get regular signals with the appropriate bits set in
> the error code field in the ucontext.  But we should probably
> simultaneously offer a nicer API, and the libraries will use it
> because it’s nicer.

FWIW, if we have a signal-based version and a VDSO-based version, nobody
will use the VDSO one.

The Intel libraries are surely going to keep using the approach they've
been using for years and I doubt their owners will be tempted even by a
simpler interface to change one line of code.

If we want to do the VDSO route, I think we probably need to go
whole-hog and toss the signal-based one.