From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To: Dave Hansen <dave.hansen@intel.com>
Cc: x86@kernel.org, platform-driver-x86@vger.kernel.org,
sean.j.christopherson@intel.com, nhorman@redhat.com,
npmccallum@redhat.com, linux-sgx@vger.kernel.org,
Suresh Siddha <suresh.b.siddha@intel.com>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
Serge Ayoun <serge.ayoun@intel.com>,
"Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
Borislav Petkov <bp@suse.de>,
Reinette Chatre <reinette.chatre@intel.com>,
Andi Kleen <ak@linux.intel.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
"open list:X86 ARCHITECTURE (32-BIT AND 64-BIT)"
<linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v13 06/13] x86/sgx: Detect Intel SGX
Date: Tue, 28 Aug 2018 11:28:11 +0300 [thread overview]
Message-ID: <20180828082811.GG15508@linux.intel.com> (raw)
In-Reply-To: <50c199b6-e8eb-9120-0d2a-5e60ac0139b4@intel.com>
On Mon, Aug 27, 2018 at 12:53:59PM -0700, Dave Hansen wrote:
> > +config INTEL_SGX_CORE
> > + prompt "Intel SGX core functionality"
> > + def_bool n
> > + depends on X86_64 && CPU_SUP_INTEL
> > + help
> > + Intel Software Guard eXtensions (SGX) is a set of CPU instructions
> > + that allows ring 3 applications to create enclaves, private regions
> > + of memory that are protected, by hardware, from unauthorized access
> > + and/or modification.
>
> This is a bit comma-crazy. Also, considering some of our recent CVE
> fun, I'd probably not claim hardware protection. :)
Agreed :)
> Maybe:
>
> Intel Software Guard eXtensions (SGX) CPU feature that allows
> ring 3 applications to create enclaves: private regions
> of memory that are architecturally protected from unauthorized
> access and/or modification.
Yeah, looks way more better structured.
> > + This option enables kernel recognition of SGX, high-level management
> > + of the Enclave Page Cache (EPC), tracking and writing of SGX Launch
> > + Enclave Hash MSRs, and allows for virtualization of SGX via KVM. By
> > + iteslf, this option does not provide SGX support to userspace.
>
> itself
>
>
> > diff --git a/arch/x86/include/asm/sgx_pr.h b/arch/x86/include/asm/sgx_pr.h
> > new file mode 100644
> > index 000000000000..c68578127620
> > --- /dev/null
> > +++ b/arch/x86/include/asm/sgx_pr.h
> > @@ -0,0 +1,13 @@
> > +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
> > +// Copyright(c) 2016-17 Intel Corporation.
> > +
> > +#ifndef _ASM_X86_SGX_PR_H
> > +#define _ASM_X86_SGX_PR_H
> > +
> > +#include <linux/printk.h>
> > +#include <linux/ratelimit.h>
> > +
> > +#undef pr_fmt
> > +#define pr_fmt(fmt) "sgx: " fmt
> > +
> > +#endif /* _ASM_X86_SGX_PR_H */
>
> I don't think this belongs in a generic header. Generally, we do the
> pr_fmt stuff in .c files, not in headers. If someone includes this
> header directly or indirectly, they'll get a big surprise.
>
> If you *must* have this in a .h file, put it in
> arch/x86/kernel/cpu/intel_sgx.h or something and #include "intel_sgx.h"
> in all the .c files where you want this.
I think for intel_sgx.c (the core part) we could just manually add the
"sgx:" prefix because there are only few log messages. I would move the
definition to drivers/platform/x86/intel_sgx/sgx.h because the prefix
makes sense for all .c files there AFAIK.
> > +static __init int sgx_init(void)
> > +{
> > + unsigned long fc;
> > +
> > + if (!boot_cpu_has(X86_FEATURE_SGX))
> > + return false;
> > +
> > + if (!boot_cpu_has(X86_FEATURE_SGX1))
> > + return false;
> > +
> > + rdmsrl(MSR_IA32_FEATURE_CONTROL, fc);
> > + if (!(fc & FEATURE_CONTROL_LOCKED)) {
> > + pr_info("IA32_FEATURE_CONTROL MSR is not locked\n");
> > + return false;
> > + }
>
> This is a rather crummy error message. Doesn't this keep sgx from
> initializing? Would something like this be more informative?
>
> pr_info("failed init: IA32_FEATURE_CONTROL MSR not locked\n");
What about:
pr_err(FW_BUG "IA32_FEATURE_CONTROL MSR not locked\n");
> > + if (!(fc & FEATURE_CONTROL_SGX_ENABLE)) {
> > + pr_info("disabled by the firmware\n");
> > + return false;
> > + }
> > +
> > + if (!(fc & FEATURE_CONTROL_SGX_LE_WR))
> > + pr_info("IA32_SGXLEPUBKEYHASHn MSRs are not writable\n");
>
> How about something that might help an end user? Perhaps:
>
> pr_warn("launch configuration not available\n");
I think this message is a false flag here in the first place as KVM does
not require writable MSRs. It really should be moved to the driver.
> > + sgx_enabled = true;
> > + sgx_lc_enabled = !!(fc & FEATURE_CONTROL_SGX_LE_WR);
> > + return 0;
> > +}
> > +
> > +arch_initcall(sgx_init);
> >
>
>
/Jarkko
next prev parent reply other threads:[~2018-08-28 8:28 UTC|newest]
Thread overview: 103+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-08-27 18:53 [PATCH v13 00/13] Intel SGX1 support Jarkko Sakkinen
2018-08-27 18:53 ` [PATCH v13 01/13] x86/sgx: Update MAINTAINERS Jarkko Sakkinen
2018-09-03 12:56 ` Andy Shevchenko
2018-09-03 19:10 ` Jarkko Sakkinen
2018-08-27 18:53 ` [PATCH v13 02/13] x86/cpufeature: Add SGX and SGX_LC CPU features Jarkko Sakkinen
2018-08-28 0:07 ` Huang, Kai
2018-08-28 7:17 ` Jarkko Sakkinen
2018-08-29 7:36 ` Huang, Kai
2018-08-31 12:19 ` Jarkko Sakkinen
2018-08-31 16:18 ` Dr. Greg
2018-08-27 18:53 ` [PATCH v13 03/13] x86/cpufeatures: Add Intel-defined SGX leaf CPUID_12_EAX Jarkko Sakkinen
2018-08-27 19:39 ` Dave Hansen
2018-08-28 7:23 ` Jarkko Sakkinen
2018-08-28 10:21 ` Borislav Petkov
2018-08-28 10:38 ` Jarkko Sakkinen
2018-08-27 18:53 ` [PATCH v13 04/13] x86/sgx: Architectural structures Jarkko Sakkinen
2018-08-27 19:41 ` Dave Hansen
2018-08-28 8:08 ` Jarkko Sakkinen
2018-09-03 13:16 ` Andy Shevchenko
2018-09-03 19:17 ` Jarkko Sakkinen
2018-09-04 16:04 ` Dave Hansen
2018-09-04 16:06 ` Andy Shevchenko
2018-09-05 17:32 ` Jarkko Sakkinen
2018-08-27 18:53 ` [PATCH v13 05/13] x86/msr: Add SGX definitions to msr-index.h Jarkko Sakkinen
2018-08-27 19:42 ` Dave Hansen
2018-08-28 8:11 ` Jarkko Sakkinen
2018-08-27 18:53 ` [PATCH v13 06/13] x86/sgx: Detect Intel SGX Jarkko Sakkinen
2018-08-27 19:53 ` Dave Hansen
2018-08-28 8:28 ` Jarkko Sakkinen [this message]
2018-09-03 14:26 ` Andy Shevchenko
2018-09-04 9:56 ` Jarkko Sakkinen
2018-08-27 18:53 ` [PATCH v13 07/13] x86/sgx: Add data structures for tracking the EPC pages Jarkko Sakkinen
2018-08-27 21:07 ` Dave Hansen
2018-08-28 10:30 ` Jarkko Sakkinen
2018-08-28 16:53 ` Dave Hansen
2018-08-28 21:34 ` Sean Christopherson
2018-08-31 11:13 ` Jarkko Sakkinen
2018-08-31 11:10 ` Jarkko Sakkinen
2018-09-03 14:41 ` Andy Shevchenko
2018-09-04 9:59 ` Jarkko Sakkinen
2018-09-04 17:49 ` Sean Christopherson
2018-09-04 18:01 ` Andy Shevchenko
2018-09-04 18:17 ` Sean Christopherson
2018-09-05 17:36 ` Jarkko Sakkinen
2018-08-27 18:53 ` [PATCH v13 08/13] x86/sgx: Add wrappers for ENCLS leaf functions Jarkko Sakkinen
2018-09-03 15:01 ` Andy Shevchenko
2018-09-04 11:09 ` Jarkko Sakkinen
2018-08-27 18:53 ` [PATCH v13 09/13] x86/sgx: Enclave Page Cache (EPC) memory manager Jarkko Sakkinen
2018-08-27 21:14 ` Dave Hansen
2018-08-28 8:36 ` Jarkko Sakkinen
2018-08-27 21:15 ` Dave Hansen
2018-08-28 8:35 ` Jarkko Sakkinen
2018-08-28 14:07 ` Dave Hansen
2018-08-28 21:22 ` Sean Christopherson
2018-08-28 21:26 ` Dave Hansen
2018-08-28 21:52 ` Sean Christopherson
2018-08-31 11:22 ` Jarkko Sakkinen
2018-09-03 19:02 ` Andy Shevchenko
2018-09-04 15:38 ` Jarkko Sakkinen
2018-09-04 15:45 ` Sean Christopherson
2018-09-11 15:04 ` Sean Christopherson
2018-09-16 11:40 ` Jarkko Sakkinen
2018-08-27 18:53 ` [PATCH v13 10/13] x86/sgx: Add sgx_einit() for initializing enclaves Jarkko Sakkinen
2018-08-27 21:41 ` Huang, Kai
2018-08-28 7:01 ` Jarkko Sakkinen
2018-08-29 7:33 ` Huang, Kai
2018-08-29 20:33 ` Sean Christopherson
2018-08-29 20:58 ` Huang, Kai
2018-08-29 21:09 ` Sean Christopherson
2018-08-30 1:45 ` Huang, Kai
2018-08-31 17:43 ` Sean Christopherson
2018-08-31 21:34 ` Dr. Greg
2018-09-03 19:27 ` Jarkko Sakkinen
2018-09-03 18:15 ` Jarkko Sakkinen
2018-08-31 12:17 ` Jarkko Sakkinen
2018-08-31 18:15 ` Sean Christopherson
2018-09-03 19:19 ` Jarkko Sakkinen
2018-09-03 23:45 ` Huang, Kai
2018-09-04 14:54 ` Sean Christopherson
2018-09-04 15:30 ` Jarkko Sakkinen
2018-09-04 16:35 ` Sean Christopherson
2018-09-04 22:13 ` Huang, Kai
2018-09-05 17:39 ` Jarkko Sakkinen
2018-09-04 15:26 ` Jarkko Sakkinen
2018-09-03 13:53 ` Jann Horn
2018-09-04 9:55 ` Jarkko Sakkinen
2018-09-04 16:05 ` Andy Shevchenko
2018-08-27 18:53 ` [PATCH v13 11/13] platform/x86: Intel SGX driver Jarkko Sakkinen
2018-09-04 17:59 ` Andy Shevchenko
2018-09-05 17:33 ` Jarkko Sakkinen
2018-09-05 17:36 ` Andy Shevchenko
2018-09-06 9:21 ` Jarkko Sakkinen
2018-09-06 17:35 ` Miguel Ojeda
2018-09-07 0:50 ` Joe Perches
2018-09-07 17:02 ` Sean Christopherson
2018-09-10 18:37 ` Jarkko Sakkinen
2018-09-10 21:22 ` Joe Perches
2018-09-10 18:33 ` Jarkko Sakkinen
2018-08-27 18:53 ` [PATCH v13 12/13] platform/x86: ptrace() support for the " Jarkko Sakkinen
2018-08-27 18:53 ` [PATCH v13 13/13] x86/sgx: Driver documentation Jarkko Sakkinen
2018-08-27 19:40 ` Randy Dunlap
2018-08-28 7:58 ` Jarkko Sakkinen
2018-08-28 8:03 ` 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=20180828082811.GG15508@linux.intel.com \
--to=jarkko.sakkinen@linux.intel.com \
--cc=ak@linux.intel.com \
--cc=bp@suse.de \
--cc=dave.hansen@intel.com \
--cc=gregkh@linuxfoundation.org \
--cc=hpa@zytor.com \
--cc=kirill.shutemov@linux.intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-sgx@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=nhorman@redhat.com \
--cc=npmccallum@redhat.com \
--cc=platform-driver-x86@vger.kernel.org \
--cc=rafael.j.wysocki@intel.com \
--cc=reinette.chatre@intel.com \
--cc=sean.j.christopherson@intel.com \
--cc=serge.ayoun@intel.com \
--cc=suresh.b.siddha@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).