From: Dave Hansen <dave.hansen@intel.com>
To: Jarkko Sakkinen <jarkko@kernel.org>,
"Dhanraj, Vijay" <vijay.dhanraj@intel.com>
Cc: "Chatre, Reinette" <reinette.chatre@intel.com>,
"dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>,
"tglx@linutronix.de" <tglx@linutronix.de>,
"bp@alien8.de" <bp@alien8.de>,
"Lutomirski, Andy" <luto@kernel.org>,
"mingo@redhat.com" <mingo@redhat.com>,
"linux-sgx@vger.kernel.org" <linux-sgx@vger.kernel.org>,
"x86@kernel.org" <x86@kernel.org>, "Christopherson,,
Sean" <seanjc@google.com>, "Huang, Kai" <kai.huang@intel.com>,
"Zhang, Cathy" <cathy.zhang@intel.com>,
"Xing, Cedric" <cedric.xing@intel.com>,
"Huang, Haitao" <haitao.huang@intel.com>,
"Shanahan, Mark" <mark.shanahan@intel.com>,
"hpa@zytor.com" <hpa@zytor.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH V2 16/32] x86/sgx: Support restricting of enclave page permissions
Date: Mon, 28 Feb 2022 07:16:22 -0800 [thread overview]
Message-ID: <f6a256a6-a7d7-a8e7-c9a8-e232203c63af@intel.com> (raw)
In-Reply-To: <Yhy/GvJegnTqYdq6@iki.fi>
On 2/28/22 04:24, Jarkko Sakkinen wrote:
>> Regarding the recent update of splitting the page permissions change
>> request into two IOCTLS (RELAX and RESTRICT), can we combine them into
>> one? That is, revert to how it was done in the v1 version?
> They are logically separate complex functionalities:
>
> 1. "restrict" calls EMODPR and requires EACCEPT
> 2. "relax" increases permissions up to vetted ("EADD") and could be
> combined with EMODPE called inside enclave.
It would be great to have a _slightly_ better justification than that.
Existing permission interfaces like chmod or mprotect() don't have this
asymmetry.
I think you're saying that the underlying hardware implementation is
asymmetric, so the interface should be too. I don't find that argument
very convincing. If the hardware interface is arcane and we can make it
look more sane in the ioctl() layer, we should that, asymmetry or not.
If we can't make it any more sane, let's say why the ioctl() must or
should be asymmetric.
The SGX2 page permission mechanism is horribly counter intuitive.
*Everybody* that looks at it thinks that it's wrong. That means that we
have a lot of work ahead of us to explain the interfaces that get
layered on top.
next prev parent reply other threads:[~2022-02-28 15:16 UTC|newest]
Thread overview: 130+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-08 0:45 [PATCH V2 00/32] x86/sgx and selftests/sgx: Support SGX2 Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 01/32] x86/sgx: Add short descriptions to ENCLS wrappers Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 02/32] x86/sgx: Add wrapper for SGX2 EMODPR function Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 03/32] x86/sgx: Add wrapper for SGX2 EMODT function Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 04/32] x86/sgx: Add wrapper for SGX2 EAUG function Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 05/32] Documentation/x86: Document SGX permission details Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 06/32] x86/sgx: Support VMA permissions more relaxed than enclave permissions Reinette Chatre
2022-03-07 17:10 ` Jarkko Sakkinen
2022-03-07 17:36 ` Reinette Chatre
2022-03-08 8:14 ` Jarkko Sakkinen
2022-03-08 9:06 ` Jarkko Sakkinen
2022-03-08 9:12 ` Jarkko Sakkinen
2022-03-08 16:04 ` Reinette Chatre
2022-03-08 17:00 ` Jarkko Sakkinen
2022-03-08 17:49 ` Reinette Chatre
2022-03-08 18:46 ` Jarkko Sakkinen
2022-03-11 11:06 ` Dr. Greg
2022-02-08 0:45 ` [PATCH V2 07/32] x86/sgx: Add pfn_mkwrite() handler for present PTEs Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 08/32] x86/sgx: x86/sgx: Add sgx_encl_page->vm_run_prot_bits for dynamic permission changes Reinette Chatre
2022-03-04 8:55 ` Jarkko Sakkinen
2022-03-04 19:19 ` Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 09/32] x86/sgx: Export sgx_encl_ewb_cpumask() Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 10/32] x86/sgx: Rename sgx_encl_ewb_cpumask() as sgx_encl_cpumask() Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 11/32] x86/sgx: Move PTE zap code to new sgx_zap_enclave_ptes() Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 12/32] x86/sgx: Make sgx_ipi_cb() available internally Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 13/32] x86/sgx: Create utility to validate user provided offset and length Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 14/32] x86/sgx: Keep record of SGX page type Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 15/32] x86/sgx: Support relaxing of enclave page permissions Reinette Chatre
2022-03-04 8:59 ` Jarkko Sakkinen
2022-02-08 0:45 ` [PATCH V2 16/32] x86/sgx: Support restricting " Reinette Chatre
2022-02-21 0:49 ` Jarkko Sakkinen
2022-02-22 18:35 ` Reinette Chatre
2022-02-23 15:46 ` Jarkko Sakkinen
2022-02-23 19:55 ` Reinette Chatre
2022-02-28 12:27 ` Jarkko Sakkinen
2022-02-23 19:21 ` Dhanraj, Vijay
2022-02-23 22:42 ` Reinette Chatre
2022-02-28 12:24 ` Jarkko Sakkinen
2022-02-28 13:19 ` Jarkko Sakkinen
2022-02-28 15:16 ` Dave Hansen [this message]
2022-02-28 17:44 ` Dhanraj, Vijay
2022-03-01 13:26 ` Jarkko Sakkinen
2022-03-01 13:42 ` Jarkko Sakkinen
2022-03-01 17:48 ` Reinette Chatre
2022-03-02 2:05 ` Jarkko Sakkinen
2022-03-02 2:11 ` Jarkko Sakkinen
2022-03-02 4:03 ` Jarkko Sakkinen
2022-03-02 22:57 ` Reinette Chatre
2022-03-03 16:08 ` Haitao Huang
2022-03-03 21:23 ` Reinette Chatre
2022-03-03 21:44 ` Dave Hansen
2022-03-05 3:19 ` Jarkko Sakkinen
2022-03-06 0:15 ` Jarkko Sakkinen
2022-03-06 0:25 ` Jarkko Sakkinen
2022-03-10 5:43 ` Jarkko Sakkinen
2022-03-10 5:59 ` Jarkko Sakkinen
2022-03-03 23:18 ` Jarkko Sakkinen
2022-03-04 4:03 ` Haitao Huang
2022-03-04 8:30 ` Jarkko Sakkinen
2022-03-04 15:51 ` Haitao Huang
2022-03-05 1:02 ` Jarkko Sakkinen
2022-03-06 14:24 ` Haitao Huang
2022-03-03 23:12 ` Jarkko Sakkinen
2022-03-04 0:48 ` Reinette Chatre
2022-03-10 6:10 ` Jarkko Sakkinen
2022-03-10 18:33 ` Haitao Huang
2022-03-11 12:10 ` Jarkko Sakkinen
2022-03-11 12:16 ` Jarkko Sakkinen
2022-03-11 12:33 ` Jarkko Sakkinen
2022-03-11 17:53 ` Reinette Chatre
2022-03-11 18:11 ` Jarkko Sakkinen
2022-03-11 19:28 ` Reinette Chatre
2022-03-14 3:42 ` Jarkko Sakkinen
2022-03-14 3:45 ` Jarkko Sakkinen
2022-03-14 3:54 ` Jarkko Sakkinen
2022-03-14 15:32 ` Reinette Chatre
2022-03-17 4:30 ` Jarkko Sakkinen
2022-03-17 22:08 ` Reinette Chatre
2022-03-17 22:51 ` Jarkko Sakkinen
2022-03-18 0:11 ` Reinette Chatre
2022-03-20 0:24 ` Jarkko Sakkinen
2022-03-28 23:22 ` Reinette Chatre
2022-03-30 15:00 ` Jarkko Sakkinen
2022-03-30 15:02 ` Jarkko Sakkinen
2022-03-14 2:49 ` Jarkko Sakkinen
2022-03-14 2:50 ` Jarkko Sakkinen
2022-03-14 2:58 ` Jarkko Sakkinen
2022-03-14 15:39 ` Haitao Huang
2022-03-17 4:34 ` Jarkko Sakkinen
2022-03-17 14:42 ` Haitao Huang
2022-03-17 4:37 ` Jarkko Sakkinen
2022-03-17 14:47 ` Haitao Huang
2022-03-17 7:01 ` Jarkko Sakkinen
2022-03-17 7:11 ` Jarkko Sakkinen
2022-03-17 14:28 ` Haitao Huang
2022-03-17 21:50 ` Jarkko Sakkinen
2022-03-17 22:00 ` Jarkko Sakkinen
2022-03-17 22:23 ` Jarkko Sakkinen
2022-02-08 0:45 ` [PATCH V2 17/32] selftests/sgx: Add test for EPCM permission changes Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 18/32] selftests/sgx: Add test for TCS page " Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 19/32] x86/sgx: Support adding of pages to an initialized enclave Reinette Chatre
2022-02-19 11:57 ` Jarkko Sakkinen
2022-02-19 12:01 ` Jarkko Sakkinen
2022-02-20 18:40 ` Jarkko Sakkinen
2022-02-22 19:19 ` Reinette Chatre
2022-02-23 15:46 ` Jarkko Sakkinen
2022-03-07 16:16 ` Jarkko Sakkinen
2022-02-08 0:45 ` [PATCH V2 20/32] x86/sgx: Tighten accessible memory range after enclave initialization Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 21/32] selftests/sgx: Test two different SGX2 EAUG flows Reinette Chatre
2022-03-07 16:39 ` Jarkko Sakkinen
2022-02-08 0:45 ` [PATCH V2 22/32] x86/sgx: Support modifying SGX page type Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 23/32] x86/sgx: Support complete page removal Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 24/32] Documentation/x86: Introduce enclave runtime management section Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 25/32] selftests/sgx: Introduce dynamic entry point Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 26/32] selftests/sgx: Introduce TCS initialization enclave operation Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 27/32] selftests/sgx: Test complete changing of page type flow Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 28/32] selftests/sgx: Test faulty enclave behavior Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 29/32] selftests/sgx: Test invalid access to removed enclave page Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 30/32] selftests/sgx: Test reclaiming of untouched page Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 31/32] x86/sgx: Free up EPC pages directly to support large page ranges Reinette Chatre
2022-02-08 0:45 ` [PATCH V2 32/32] selftests/sgx: Page removal stress test Reinette Chatre
2022-02-22 20:27 ` [PATCH V2 00/32] x86/sgx and selftests/sgx: Support SGX2 Nathaniel McCallum
2022-02-22 22:39 ` Reinette Chatre
2022-02-23 13:24 ` Nathaniel McCallum
2022-02-23 18:25 ` Reinette Chatre
2022-03-02 16:57 ` Nathaniel McCallum
2022-03-02 21:20 ` Reinette Chatre
2022-03-03 1:13 ` Nathaniel McCallum
2022-03-03 17:49 ` Reinette Chatre
2022-03-04 0:57 ` Jarkko Sakkinen
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