| |
|
 |
|
 |
|
|
|
| |
|
|
xen-devel
Re: [Xen-devel] RE: [PATCH 5/7] xen/acpi: Domain0 acpi parser related pl
|
To: |
"Cihula, Joseph" <joseph.cihula@xxxxxxxxx>, liang tang <liang.tang@xxxxxxxxxx> |
|
Subject: |
Re: [Xen-devel] RE: [PATCH 5/7] xen/acpi: Domain0 acpi parser related platform hypercall |
|
From: |
Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx> |
|
Date: |
Thu, 22 Sep 2011 08:51:42 -0400 |
|
Cc: |
"Brown, Len" <len.brown@xxxxxxxxx>, "Tian, Kevin" <kevin.tian@xxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>, "keir@xxxxxxx" <keir@xxxxxxx>, "x86@xxxxxxxxxx" <x86@xxxxxxxxxx>, Jeremy Fitzhardinge <jeremy@xxxxxxxx>, "linux-acpi@xxxxxxxxxxxxxxx" <linux-acpi@xxxxxxxxxxxxxxx>, "tboot-devel@xxxxxxxxxxxxxxxxxxxxx" <tboot-devel@xxxxxxxxxxxxxxxxxxxxx>, Fitzhardinge <jeremy.fitzhardinge@xxxxxxxxxx>, "liang.tang@xxxxxxxxxx" <liang.tang@xxxxxxxxxx>, "Yu, Ke" <ke.yu@xxxxxxxxx>, "hpa@xxxxxxxxx" <hpa@xxxxxxxxx>, "tglx@xxxxxxxxxxxxx" <tglx@xxxxxxxxxxxxx>, "linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx" <linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx>, "Wei, Gang" <gang.wei@xxxxxxxxx> |
|
Delivery-date: |
Thu, 22 Sep 2011 05:53:46 -0700 |
|
Envelope-to: |
www-data@xxxxxxxxxxxxxxxxxxx |
|
In-reply-to: |
<20110908133847.GC27132@xxxxxxxxxxxx> |
|
List-help: |
<mailto:xen-devel-request@lists.xensource.com?subject=help> |
|
List-id: |
Xen developer discussion <xen-devel.lists.xensource.com> |
|
List-post: |
<mailto:xen-devel@lists.xensource.com> |
|
List-subscribe: |
<http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe> |
|
List-unsubscribe: |
<http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe> |
|
References: |
<1314815484-4668-1-git-send-email-konrad.wilk@xxxxxxxxxx> <1314815484-4668-6-git-send-email-konrad.wilk@xxxxxxxxxx> <9F57BF860713DF4BA3EFA4F8C6DFEDAC16F3F665@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> <4E67A9E7.2020802@xxxxxxxx> <9F57BF860713DF4BA3EFA4F8C6DFEDAC16F40F0B@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> <20110907190659.GH7074@xxxxxxxxxxxx> <20110908133847.GC27132@xxxxxxxxxxxx> |
|
Sender: |
xen-devel-bounces@xxxxxxxxxxxxxxxxxxx |
|
User-agent: |
Mutt/1.5.21 (2010-09-15) |
On Thu, Sep 08, 2011 at 09:38:48AM -0400, Konrad Rzeszutek Wilk wrote:
> On Wed, Sep 07, 2011 at 03:06:59PM -0400, Konrad Rzeszutek Wilk wrote:
> > > > >> +#define XENPF_enter_acpi_sleep 51
> > > > >> +struct xenpf_enter_acpi_sleep {
> > > > >> + /* IN variables */
> > > > >> + uint16_t pm1a_cnt_val; /* PM1a control value. */
> > > > >> + uint16_t pm1b_cnt_val; /* PM1b control value. */
> > > > > These are uint32_t in native Linux--why truncate in the API and not
> > > > > at use?
> > > >
> > > > Does ACPI define them as 32 or 16 bit?
> > >
> > > The spec indicates that the length is variable and could be up to 32 bits
> > > (AFAICT). And Linux uses 32b, which your other patch is truncating for
> > > this call.
> >
> > Yikes! Well, looks like we need to fix the Xen ABI too. Lets get that fixed
> > and also address all the other comments (thanks for looking at it) you
> > pointed
> > out.
>
> So read up the ACPI spec and it says that the minimum is 2 bytes and does not
> say anything about the maximum. The list of what the bits do stops at 16-bits
> (the last two are reserved) so I think we are actually OK.
Perhaps a better way of doing this is in the hypercall (in the Linux kernel)
check if the other 16-bits have any value. And if so WARN (with an appropiate
message to email xen-devel) and also bail out on making the hypercall. That
way we can find out about this.
>
> Albeit if the spec starts using more of them - then yes we will need to revist
> this Xen ABI and potentially add a new call.
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
|
|
| |
|
Home