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Subject: Re: [PATCH v36 21/24] x86/vdso: Implement a vDSO for Intel SGX
 enclave call
To:     Sean Christopherson <sean.j.christopherson@intel.com>,
        Nathaniel McCallum <npmccallum@redhat.com>
Cc:     Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>, x86@kernel.org,
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 <20200716135303.276442-22-jarkko.sakkinen@linux.intel.com>
 <CAOASepOqRfUafSv_qjUv-jW_6n8G7kZ9yh-2z_Z9sjL_2zqNCg@mail.gmail.com>
 <20200810222317.GG14724@linux.intel.com>
From:   Jethro Beekman <jethro@fortanix.com>
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Date:   Tue, 11 Aug 2020 09:16:28 +0200
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On 2020-08-11 00:23, Sean Christopherson wrote:
> Another thought would be to wrap sgx_enclave_exception in a struct to g=
ive
> room for supporting additional exit information (if such a thing ever p=
ops
> up) and to allow the caller to opt in to select behavior, e.g. Jethro's=

> request to invoke the exit handler on IRQ exits.  This is basically the=

> equivalent of "struct kvm_run", minus the vCPU/enclave state.

Actually, the flag I need is =E2=80=9Creturn from the vdso on IRQ exits=E2=
=80=9D (See Andy's email about preferring returns over callbacks). But ma=
ybe the flag should be =E2=80=9Cinterpret IRQ exit as a normal exit=E2=80=
=9D and let it be handled the same as any other exit based on whether an =
exit handler fnptr was passed or not.

--
Jethro Beekman | Fortanix


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