From: Ian Campbell <Ian.Campbell@citrix.com>
To: Jan Beulich <JBeulich@suse.com>
Cc: keir@xen.org, eddie.dong@intel.com,
stefano.stabellini@eu.citrix.com, andrew.cooper3@citrix.com,
ian.jackson@eu.citrix.com, xen-devel@lists.xen.org,
jun.nakajima@intel.com, yang.z.zhang@intel.com,
Boris Ostrovsky <boris.ostrovsky@oracle.com>
Subject: Re: [PATCH v5 1/4] xen/libxc: Allow changes to hypervisor CPUID leaf from config file
Date: Wed, 19 Mar 2014 09:52:22 +0000 [thread overview]
Message-ID: <1395222742.10203.29.camel@kazak.uk.xensource.com> (raw)
In-Reply-To: <532972460200007800125962@nat28.tlf.novell.com>
On Wed, 2014-03-19 at 09:32 +0000, Jan Beulich wrote:
> >>> On 19.03.14 at 10:27, Ian Campbell <Ian.Campbell@citrix.com> wrote:
> > On Tue, 2014-03-18 at 20:58 -0400, Boris Ostrovsky wrote:
> >> Currently only "real" cpuid leaves can be overwritten by users via
> >> 'cpuid' option in the configuration file. This patch provides ability to
> >> do the same for hypervisor leaves (but for now only 0x40000000 is allowed).
> >>
> >> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
> >> ---
> >> tools/libxc/xc_cpuid_x86.c | 71
> > ++++++++++++++++++++++++++++++++++++++++--
> >> xen/arch/x86/domain.c | 19 +++++++++--
> >> xen/arch/x86/traps.c | 3 ++
> >> xen/include/asm-x86/domain.h | 7 +++++
> >> 4 files changed, 95 insertions(+), 5 deletions(-)
> >>
> >> diff --git a/tools/libxc/xc_cpuid_x86.c b/tools/libxc/xc_cpuid_x86.c
> >> index bbbf9b8..5501d5b 100644
> >> --- a/tools/libxc/xc_cpuid_x86.c
> >> +++ b/tools/libxc/xc_cpuid_x86.c
> >> @@ -33,6 +33,8 @@
> >> #define DEF_MAX_INTELEXT 0x80000008u
> >> #define DEF_MAX_AMDEXT 0x8000001cu
> >>
> >> +#define IS_HYPERVISOR_LEAF(idx) (((idx) & 0xffff0000) == 0x40000000)
> >
> > Not idx == 0x40000000?
> >
> > Also as I think Jan said before if viridian support is enabled then the
> > Xen leaves may be elsewhere (at 0x100 increments above that address
> > IIRC).
>
> But that's exactly why the low 16 bits should be masked off in
> above comparison.
Is it 0x100 or 0x1000 increments? I thought it was 0x100, in which case
shouldn't the mask be 0xfffff000?
I think this should be clarified in the xen/include/public/cpuid.h
header, perhaps including this sort of macro for convenience.
Ian.
next prev parent reply other threads:[~2014-03-19 9:52 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-19 0:58 [PATCH v5 0/4] Expose HW APIC virtualization support to HVM guests Boris Ostrovsky
2014-03-19 0:58 ` [PATCH v5 1/4] xen/libxc: Allow changes to hypervisor CPUID leaf from config file Boris Ostrovsky
2014-03-19 9:26 ` Jan Beulich
2014-03-19 9:29 ` Ian Campbell
2014-03-19 14:26 ` Boris Ostrovsky
2014-03-19 9:27 ` Ian Campbell
2014-03-19 9:32 ` Jan Beulich
2014-03-19 9:52 ` Ian Campbell [this message]
2014-03-19 10:06 ` Jan Beulich
2014-03-19 10:39 ` Ian Campbell
2014-03-19 11:44 ` Jan Beulich
2014-03-19 12:02 ` Ian Campbell
2014-03-19 14:41 ` Boris Ostrovsky
2014-03-20 9:25 ` Ian Campbell
2014-03-20 13:50 ` Boris Ostrovsky
2014-03-19 0:58 ` [PATCH v5 2/4] x86/hvm: Revert 80ecb40362365ba77e68fc609de8bd3b7208ae19 Boris Ostrovsky
2014-03-19 0:58 ` [PATCH v5 3/4] x86/hvm: Add HVM-specific hypervisor CPUID leaf Boris Ostrovsky
2014-03-19 0:58 ` [PATCH v5 4/4] x86/hvm: Indicate avaliability of HW support of APIC virtualization to HVM guests Boris Ostrovsky
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=1395222742.10203.29.camel@kazak.uk.xensource.com \
--to=ian.campbell@citrix.com \
--cc=JBeulich@suse.com \
--cc=andrew.cooper3@citrix.com \
--cc=boris.ostrovsky@oracle.com \
--cc=eddie.dong@intel.com \
--cc=ian.jackson@eu.citrix.com \
--cc=jun.nakajima@intel.com \
--cc=keir@xen.org \
--cc=stefano.stabellini@eu.citrix.com \
--cc=xen-devel@lists.xen.org \
--cc=yang.z.zhang@intel.com \
/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.