From: Borislav Petkov <bp@alien8.de>
To: Richard Hughes <hughsient@gmail.com>
Cc: Daniel Gutson <daniel@eclypsium.com>,
Dave Hansen <dave.hansen@intel.com>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>,
x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
Arnd Bergmann <arnd@arndb.de>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Peter Zijlstra <peterz@infradead.org>,
"David S. Miller" <davem@davemloft.net>,
Rob Herring <robh@kernel.org>, Tony Luck <tony.luck@intel.com>,
Rahul Tanwar <rahul.tanwar@linux.intel.com>,
Xiaoyao Li <xiaoyao.li@intel.com>,
Sean Christopherson <sean.j.christopherson@intel.com>,
Dave Hansen <dave.hansen@linux.intel.com>,
linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] Ability to read the MKTME status from userspace
Date: Fri, 19 Jun 2020 15:44:32 +0200 [thread overview]
Message-ID: <20200619134432.GE32683@zn.tnic> (raw)
In-Reply-To: <CAD2FfiEr0kRWp2ut_PVqVDEVZqwESUxv=fxM9wUgi3n=ZCzPcQ@mail.gmail.com>
On Fri, Jun 19, 2020 at 02:31:11PM +0100, Richard Hughes wrote:
> 1. that the CPU supports TME (->cpuid, already done)
> 2. that the platform has not disabled TME in some way
Yes, this is what I'm proposing with clearing the flag in /proc/cpuinfo.
The needed information is there:
1. TME in CPUID
2. TME *not* in /proc/cpuinfo
which means the platform doesn't support it.
If we are going to export a list of features which the OS
kernel/platform has enabled - and this means a contract between kernel
and userspace - then this should not be a misc driver which gets loaded
as a module but builtin, maybe a proper sysfs layout similar to
/sys/devices/system/cpu/vulnerabilities
which userspace can use. Along with proper ABI definition, design,
documentation and all that belongs to a proper interface with userspace.
Because once userspace uses it, it is practically cast in stone.
Thx.
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
next prev parent reply other threads:[~2020-06-19 13:44 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-18 21:02 [PATCH] Ability to read the MKTME status from userspace Daniel Gutson
2020-06-18 21:08 ` Dave Hansen
[not found] ` <CAFmMkTHNxSN_uWtm63TdkGxj44NXQQKEOmATXhjA=4DSCS92kQ@mail.gmail.com>
2020-06-18 22:01 ` Borislav Petkov
[not found] ` <CAFmMkTGMAu-huTnP1aeMb_W4NddbTD_b2jhbDVKBDrkwgB97wg@mail.gmail.com>
2020-06-19 7:40 ` Borislav Petkov
[not found] ` <CAFmMkTGV0ZR6C=EBGQAiz1vw1vrUXSLTnH5ZbBUvfhPLg_tF6g@mail.gmail.com>
2020-06-19 13:22 ` Borislav Petkov
2020-06-19 13:31 ` Richard Hughes
2020-06-19 13:44 ` Borislav Petkov [this message]
2020-06-19 13:50 ` Richard Hughes
2020-06-19 15:48 ` Andy Lutomirski
2020-06-19 16:17 ` Borislav Petkov
2020-06-19 16:28 ` Andy Lutomirski
2020-06-19 16:31 ` Richard Hughes
2020-06-19 16:10 ` Borislav Petkov
2020-06-19 16:33 ` Richard Hughes
2020-06-19 16:40 ` Greg Kroah-Hartman
2020-06-19 16:47 ` Richard Hughes
2020-06-19 19:41 ` Andy Lutomirski
2020-06-19 19:58 ` Richard Hughes
2020-06-19 20:20 ` Andy Lutomirski
2020-06-19 20:24 ` Dave Hansen
2020-06-22 9:34 ` Boris Petkov
2020-06-18 23:52 ` Dave Hansen
2020-06-19 7:41 ` Borislav Petkov
2020-06-19 13:25 ` Richard Hughes
2020-06-19 13:33 ` Dave Hansen
2020-06-19 13:37 ` Richard Hughes
2020-06-19 13:58 ` Dave Hansen
2020-06-19 14:09 ` Richard Hughes
2020-06-19 14:23 ` Dave Hansen
2020-06-19 14:36 ` Richard Hughes
2020-06-19 14:48 ` Dave Hansen
2020-06-19 15:02 ` Richard Hughes
2020-06-19 15:36 ` Dave Hansen
2020-06-19 7:20 ` Greg Kroah-Hartman
[not found] ` <CAFmMkTF7QBJQdKxhsPiUPifsxykyCVv=NYandpB0z8EccAxMXw@mail.gmail.com>
2020-06-19 14:02 ` Greg Kroah-Hartman
-- strict thread matches above, loose matches on Subject: below --
2020-06-25 0:33 kernel test robot
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