From: mark gross <mgross@linux.intel.com>
To: speck@linutronix.de
Subject: [MODERATED] Re: [patch V2 03/10] MDS basics+ 3
Date: Wed, 20 Feb 2019 10:08:58 -0800 [thread overview]
Message-ID: <20190220180858.GA285@mgross-MOBL.amr.corp.intel.com> (raw)
In-Reply-To: <alpine.DEB.2.21.1902201756370.1513@nanos.tec.linutronix.de>
On Wed, Feb 20, 2019 at 05:57:04PM +0100, speck for Thomas Gleixner wrote:
> On Wed, 20 Feb 2019, speck for mark gross wrote:
> > On Wed, Feb 20, 2019 at 04:07:56PM +0100, speck for Thomas Gleixner wrote:
> > > +static inline void mds_clear_cpu_buffers(void)
> > > +{
> > > + static const u16 ds = __KERNEL_DS;
> > > +
> > > + /*
> > > + * Has to be memory form, don't modify to use a register. VERW
> > > + * modifies ZF.
> > > + */
> > > + asm volatile("verw %[ds]" : : "i" (0), [ds] "m" (ds) : "cc");
> > > +}
> > > +
> > > #endif /* __ASSEMBLY__ */
> > >
> > > /*
> > >
> > Perhaps a dumb question but, is there any point to including that fall back ASM
> > altrinitive for platfroms without the uCode update enabling verw to clear
> > buffers?
>
> See 8/10 ....
I was just wrapping my head around that one. I don't like the name for that
mode but I can't think of a better one other than MDS_GUEST_CHICKEN_BIT. Which
is worse.
Anyway, Andi pointed out off list to me that Linus rejected the ASM sequences
that could be used if verw was not available before I was on this list. So,
please ingore my initial comment as it was related to those.
--mark
next prev parent reply other threads:[~2019-02-20 18:09 UTC|newest]
Thread overview: 57+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-20 15:07 [patch V2 00/10] MDS basics+ 0 Thomas Gleixner
2019-02-20 15:07 ` [patch V2 01/10] MDS basics+ 1 Thomas Gleixner
2019-02-20 16:27 ` [MODERATED] " Borislav Petkov
2019-02-20 16:46 ` Greg KH
2019-02-20 15:07 ` [patch V2 02/10] MDS basics+ 2 Thomas Gleixner
2019-02-20 16:47 ` [MODERATED] " Borislav Petkov
2019-02-20 16:48 ` Greg KH
2019-02-20 15:07 ` [patch V2 03/10] MDS basics+ 3 Thomas Gleixner
2019-02-20 16:54 ` [MODERATED] " mark gross
2019-02-20 16:57 ` Thomas Gleixner
2019-02-20 18:08 ` mark gross [this message]
2019-02-20 21:40 ` Thomas Gleixner
2019-02-20 17:14 ` [MODERATED] " Borislav Petkov
2019-02-20 21:31 ` Thomas Gleixner
2019-02-21 2:12 ` [MODERATED] " Andrew Cooper
2019-02-21 9:27 ` Peter Zijlstra
2019-02-21 9:33 ` [MODERATED] " Borislav Petkov
2019-02-21 10:04 ` Thomas Gleixner
2019-02-21 10:18 ` [MODERATED] Re: " Borislav Petkov
2019-02-20 15:07 ` [patch V2 04/10] MDS basics+ 4 Thomas Gleixner
2019-02-20 16:52 ` [MODERATED] " Greg KH
2019-02-20 17:10 ` mark gross
2019-02-21 19:26 ` [MODERATED] Encrypted Message Tim Chen
2019-02-21 20:32 ` Thomas Gleixner
2019-02-21 21:07 ` [MODERATED] " Jiri Kosina
2019-02-20 18:43 ` [MODERATED] Re: [patch V2 04/10] MDS basics+ 4 Borislav Petkov
2019-02-20 19:26 ` Jiri Kosina
2019-02-20 21:42 ` Thomas Gleixner
2019-02-20 15:07 ` [patch V2 05/10] MDS basics+ 5 Thomas Gleixner
2019-02-20 20:05 ` [MODERATED] " Borislav Petkov
2019-02-21 2:24 ` Andrew Cooper
2019-02-21 10:36 ` Thomas Gleixner
2019-02-21 11:22 ` Thomas Gleixner
2019-02-21 11:51 ` [MODERATED] Attack Surface [Was [patch V2 05/10] MDS basics+ 5] Andrew Cooper
2019-02-21 18:41 ` Thomas Gleixner
2019-02-20 15:07 ` [patch V2 06/10] MDS basics+ 6 Thomas Gleixner
2019-02-21 10:18 ` [MODERATED] " Borislav Petkov
2019-02-20 15:08 ` [patch V2 07/10] MDS basics+ 7 Thomas Gleixner
2019-02-21 12:47 ` [MODERATED] " Borislav Petkov
2019-02-21 13:48 ` Thomas Gleixner
2019-02-20 15:08 ` [patch V2 08/10] MDS basics+ 8 Thomas Gleixner
2019-02-21 14:04 ` [MODERATED] " Borislav Petkov
2019-02-21 14:11 ` Thomas Gleixner
2019-02-20 15:08 ` [patch V2 09/10] MDS basics+ 9 Thomas Gleixner
2019-02-20 16:21 ` [MODERATED] " Peter Zijlstra
2019-02-20 22:32 ` Thomas Gleixner
2019-02-20 22:50 ` [MODERATED] " Jiri Kosina
2019-02-20 23:22 ` Thomas Gleixner
2019-02-21 11:04 ` [MODERATED] " Peter Zijlstra
2019-02-21 11:50 ` Peter Zijlstra
2019-02-21 14:18 ` Borislav Petkov
2019-02-21 18:00 ` Kees Cook
2019-02-21 19:46 ` Thomas Gleixner
2019-02-21 20:56 ` Thomas Gleixner
2019-02-20 15:08 ` [patch V2 10/10] MDS basics+ 10 Thomas Gleixner
2019-02-22 16:05 ` [MODERATED] Re: [patch V2 00/10] MDS basics+ 0 mark gross
2019-02-22 17:12 ` Thomas Gleixner
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=20190220180858.GA285@mgross-MOBL.amr.corp.intel.com \
--to=mgross@linux.intel.com \
--cc=speck@linutronix.de \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.