xen-devel.lists.xenproject.org archive mirror
 help / color / mirror / Atom feed
From: "Jan Beulich" <JBeulich@suse.com>
To: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>,
	xen-devel <xen-devel@lists.xenproject.org>
Subject: Re: [PATCH 1/2] hvmloader: limit CPUs exposed to guests
Date: Thu, 16 Jun 2016 09:25:04 -0600	[thread overview]
Message-ID: <5762E0F002000078000F5C06@prv-mh.provo.novell.com> (raw)
In-Reply-To: <5762C111.5050600@oracle.com>

>>> On 16.06.16 at 17:09, <boris.ostrovsky@oracle.com> wrote:
> On 06/16/2016 05:40 AM, Jan Beulich wrote:
> 
> --- a/tools/firmware/hvmloader/acpi/mk_dsdt.c
> +++ b/tools/firmware/hvmloader/acpi/mk_dsdt.c
> @@ -150,6 +150,14 @@ int main(int argc, char **argv)
>      indent(); printf("MSU, 8\n");
>      pop_block();
>  
> +    /* Processor object helpers. */
> +    push_block("Method", "PMAT, 2");
> +    push_block("If", "LLess(Arg0, NCPU)");
> +    stmt("Return", "ToBuffer(Arg1)");
> +    pop_block();
> +    stmt("Return", "Buffer() {0, 8, 0xff, 0xff, 0, 0, 0, 0}");
> 
> 
> Could you explain what this is? (I suspect  this is related to MAT
> object and I don't think I understand what it is).

This is a helper routine for _MAT(), helping greatly to reduce
overall size of the DSDT. It checks whether the CPU is within the
range of available ones (online or offline), and if it isn't returns a
static buffer instead of data read from MADT (as it's the purpose
of this patch to remove these MADT entries for not present CPUs).

Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel

  reply	other threads:[~2016-06-16 15:25 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-06-16  9:33 [PATCH 0/2] x86: hvmloader improvements Jan Beulich
2016-06-16  9:40 ` [PATCH 1/2] hvmloader: limit CPUs exposed to guests Jan Beulich
2016-06-16 15:09   ` Boris Ostrovsky
2016-06-16 15:25     ` Jan Beulich [this message]
2016-06-16 15:37       ` Boris Ostrovsky
2016-06-16 16:04         ` Jan Beulich
2016-06-16 16:38           ` Boris Ostrovsky
2016-06-17  9:40   ` Andrew Cooper
2016-06-16  9:40 ` [PATCH 2/2] hvmloader: don't hard-code IO-APIC parameters Jan Beulich
2016-06-16 16:49   ` Boris Ostrovsky
2016-06-17  6:00     ` Jan Beulich
2016-06-17 11:51       ` Boris Ostrovsky
2016-06-17 14:26         ` Jan Beulich
2016-06-17 10:05   ` Andrew Cooper
2016-06-17 10:23     ` Jan Beulich

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=5762E0F002000078000F5C06@prv-mh.provo.novell.com \
    --to=jbeulich@suse.com \
    --cc=andrew.cooper3@citrix.com \
    --cc=boris.ostrovsky@oracle.com \
    --cc=xen-devel@lists.xenproject.org \
    --subject='Re: [PATCH 1/2] hvmloader: limit CPUs exposed to guests' \
    /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

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).