From: Sean Christopherson <sean.j.christopherson@intel.com>
To: Borislav Petkov <bp@alien8.de>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
linux-kernel@vger.kernel.org, x86@kernel.org,
linux-sgx@vger.kernel.org, akpm@linux-foundation.org,
dave.hansen@intel.com, nhorman@redhat.com, npmccallum@redhat.com,
serge.ayoun@intel.com, shay.katz-zamir@intel.com,
haitao.huang@intel.com, andriy.shevchenko@linux.intel.com,
tglx@linutronix.de, kai.svahn@intel.com, josh@joshtriplett.org,
luto@kernel.org, kai.huang@intel.com, rientjes@google.com,
cedric.xing@intel.com, puiterwijk@redhat.com
Subject: Re: [PATCH v24 07/24] x86/cpu/intel: Detect SGX supprt
Date: Tue, 14 Jan 2020 10:36:16 -0800 [thread overview]
Message-ID: <20200114183615.GH16784@linux.intel.com> (raw)
In-Reply-To: <20191223094614.GB16710@zn.tnic>
On Mon, Dec 23, 2019 at 10:46:14AM +0100, Borislav Petkov wrote:
> On Sat, Nov 30, 2019 at 01:13:09AM +0200, Jarkko Sakkinen wrote:
> > From: Sean Christopherson <sean.j.christopherson@intel.com>
> >
> > When the CPU supports SGX, check that the BIOS has enabled SGX and SGX1
> > opcodes are available. Otherwise, all the SGX related capabilities.
> >
> > In addition, clear X86_FEATURE_SGX_LC also in the case when the launch
> > enclave are read-only. This way the feature bit reflects the level that
> > Linux supports the launch control.
> >
> > The check is done for every CPU, not just BSP, in order to verify that
> > MSR_IA32_FEATURE_CONTROL is correctly configured on all CPUs. The other
> > parts of the kernel, like the enclave driver, expect the same
> > configuration from all CPUs.
> >
> > Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
> > Co-developed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> > ---
> > arch/x86/kernel/cpu/intel.c | 41 +++++++++++++++++++++++++++++++++++++
> > 1 file changed, 41 insertions(+)
> >
> > diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
> > index c2fdc00df163..89a71367716c 100644
> > --- a/arch/x86/kernel/cpu/intel.c
> > +++ b/arch/x86/kernel/cpu/intel.c
> > @@ -624,6 +624,42 @@ static void detect_tme(struct cpuinfo_x86 *c)
> > c->x86_phys_bits -= keyid_bits;
> > }
> >
> > +static void __maybe_unused detect_sgx(struct cpuinfo_x86 *c)
> > +{
> > + unsigned long long fc;
> > +
> > + rdmsrl(MSR_IA32_FEATURE_CONTROL, fc);
> > + if (!(fc & FEATURE_CONTROL_LOCKED)) {
> > + pr_err_once("sgx: The feature control MSR is not locked\n");
> > + goto err_unsupported;
> > + }
> > +
> > + if (!(fc & FEATURE_CONTROL_SGX_ENABLE)) {
> > + pr_err_once("sgx: SGX is not enabled in IA32_FEATURE_CONTROL MSR\n");
> > + goto err_unsupported;
> > + }
> > +
> > + if (!cpu_has(c, X86_FEATURE_SGX1)) {
> > + pr_err_once("sgx: SGX1 instruction set is not supported\n");
> > + goto err_unsupported;
> > + }
> > +
> > + if (!(fc & FEATURE_CONTROL_SGX_LE_WR)) {
> > + pr_info_once("sgx: The launch control MSRs are not writable\n");
> > + goto err_msrs_rdonly;
> > + }
>
> One more thing - and we talked about this already - when the hash
> MSRs are not writable, the kernel needs to disable all SGX support by
> default. Basically, no SGX support is present.
Yep.
> If the user wants to run KVM guests with SGX enclaves, then she should
> probably boot with a special kvm param or so. Details on how can exactly
> control that can be discussed later - just making sure you guys are not
> forgetting this use angle.
Ya, planning on having a 'sgx' KVM module param. It could take a string
if we want to allow the admin to enable SGX virtualization if and only if
SGX LC is fully enabled, e.g. sgx='off|on|lc'.
next prev parent reply other threads:[~2020-01-14 18:36 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-29 23:13 [PATCH v24 00/24] Intel SGX foundations Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 01/24] x86/sgx: Update MAINTAINERS Jarkko Sakkinen
2019-11-30 1:38 ` Neil Horman
2019-11-30 14:37 ` Dr. Greg
2019-12-02 9:24 ` Jethro Beekman
2019-12-06 21:23 ` Jarkko Sakkinen
2019-12-06 21:24 ` Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 02/24] x86/cpufeatures: x86/msr: Add Intel SGX hardware bits Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 03/24] x86/cpufeatures: x86/msr: Intel SGX Launch Control " Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 04/24] x86/mm: x86/sgx: Signal SIGSEGV with PF_SGX Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 05/24] x86/sgx: Add SGX microarchitectural data structures Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 06/24] x86/sgx: Add wrappers for ENCLS leaf functions Jarkko Sakkinen
2019-12-17 14:45 ` Borislav Petkov
2019-12-19 0:39 ` Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 07/24] x86/cpu/intel: Detect SGX supprt Jarkko Sakkinen
2019-12-17 15:17 ` Borislav Petkov
2019-12-19 0:42 ` Jarkko Sakkinen
2019-12-19 6:15 ` Borislav Petkov
2019-12-23 9:46 ` Borislav Petkov
2019-12-27 6:00 ` Jarkko Sakkinen
2020-01-14 18:36 ` Sean Christopherson [this message]
2019-11-29 23:13 ` [PATCH v24 08/24] x86/sgx: Enumerate and track EPC sections Jarkko Sakkinen
2019-12-18 9:18 ` Borislav Petkov
2019-12-18 15:19 ` Sean Christopherson
2019-12-18 16:18 ` Borislav Petkov
2019-12-19 0:53 ` Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 09/24] x86/sgx: Add functions to allocate and free EPC pages Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 10/24] x86/sgx: Add sgx_einit() for wrapping ENCLS[EINIT] Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 11/24] mm: Introduce vm_ops->may_mprotect() Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 12/24] x86/sgx: Linux Enclave Driver Jarkko Sakkinen
2019-12-02 15:48 ` Haitao Huang
2019-12-02 18:21 ` Sean Christopherson
2019-12-09 19:38 ` Jarkko Sakkinen
2019-12-09 19:08 ` Jarkko Sakkinen
2020-01-14 16:12 ` Haitao Huang
2020-01-23 12:31 ` Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 13/24] selftests/x86: Recurse into subdirectories Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 14/24] selftests/x86: Add a selftest for SGX Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 15/24] x86/sgx: Add provisioning Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 16/24] x86/sgx: Add a page reclaimer Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 17/24] x86/sgx: ptrace() support for the SGX driver Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 18/24] x86/vdso: Add support for exception fixup in vDSO functions Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 19/24] x86/fault: Add helper function to sanitize error code Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 20/24] x86/traps: Attempt to fixup exceptions in vDSO before signaling Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 21/24] x86/vdso: Add __vdso_sgx_enter_enclave() to wrap SGX enclave transitions Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 22/24] selftests/x86: Add vDSO selftest for SGX Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 23/24] docs: x86/sgx: Document microarchitecture Jarkko Sakkinen
2019-11-29 23:13 ` [PATCH v24 24/24] docs: x86/sgx: Document kernel internals Jarkko Sakkinen
2019-12-20 13:26 ` [PATCH v24 00/24] Intel SGX foundations Nathaniel McCallum
2020-02-24 6:34 ` 三仟(惠春阳)
2020-02-25 10:15 ` Jarkko Sakkinen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200114183615.GH16784@linux.intel.com \
--to=sean.j.christopherson@intel.com \
--cc=akpm@linux-foundation.org \
--cc=andriy.shevchenko@linux.intel.com \
--cc=bp@alien8.de \
--cc=cedric.xing@intel.com \
--cc=dave.hansen@intel.com \
--cc=haitao.huang@intel.com \
--cc=jarkko.sakkinen@linux.intel.com \
--cc=josh@joshtriplett.org \
--cc=kai.huang@intel.com \
--cc=kai.svahn@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-sgx@vger.kernel.org \
--cc=luto@kernel.org \
--cc=nhorman@redhat.com \
--cc=npmccallum@redhat.com \
--cc=puiterwijk@redhat.com \
--cc=rientjes@google.com \
--cc=serge.ayoun@intel.com \
--cc=shay.katz-zamir@intel.com \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).