public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: "Roger Pau Monné" <roger.pau@citrix.com>
To: Ian Campbell <Ian.Campbell@citrix.com>,
	Julien Grall <julien.grall@linaro.org>
Cc: <xen-devel@lists.xenproject.org>,
	Stefano Stabellini <stefano.stabellini@eu.citrix.com>,
	<linux-kernel@vger.kernel.org>,
	David Vrabel <david.vrabel@citrix.com>, <patches@linaro.org>,
	Boris Ostrovsky <boris.ostrovsky@oracle.com>,
	<linux-arm-kernel@lists.infradead.org>
Subject: Re: [Xen-devel] [PATCH v2] xen/block: Correctly define structures in public headers on ARM32 and ARM64
Date: Thu, 12 Dec 2013 16:11:59 +0100	[thread overview]
Message-ID: <52A9D23F.3010005@citrix.com> (raw)
In-Reply-To: <1386857960.11201.57.camel@kazak.uk.xensource.com>

On 12/12/13 15:19, Ian Campbell wrote:
> On Tue, 2013-12-03 at 15:40 +0000, Julien Grall wrote:
>> On ARM (32 bits and 64 bits), the double-word is 8-bytes aligned. This will
>> result on different structure from Xen and Linux repositories.
>>
>> As Linux is using __packed__ attribute, it must have a 4-bytes padding before
>> each "id" field.
>>
>> This change breaks guest block support with older kernel. IMHO, it's acceptable
>> because Xen on ARM is still on Tech Preview and the hypercall ABI is not yet
>> freezed.
>>
>> Only one architecture (x86_32) doesn't have 64-bit ABI for the block interface.
>> Don't add padding if Linux is compiled for this architecture.
> 
> Konrad asked for confirmation that this didn't change x86.

I've also tested this using various combinations of kernels, and it
seems to be perfectly fine, so:

Acked-by: Roger Pau Monné <roger.pau@citrix.com>


      reply	other threads:[~2013-12-12 15:12 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-12-03 15:40 [PATCH v2] xen/block: Correctly define structures in public headers on ARM32 and ARM64 Julien Grall
2013-12-03 16:00 ` One Thousand Gnomes
2013-12-03 16:19   ` Julien Grall
2013-12-03 16:32     ` One Thousand Gnomes
2013-12-03 16:41       ` Ian Campbell
2013-12-03 17:03         ` One Thousand Gnomes
2013-12-03 18:03           ` Konrad Rzeszutek Wilk
2013-12-03 17:10 ` David Vrabel
2013-12-03 18:01   ` Konrad Rzeszutek Wilk
2013-12-12 14:19 ` [Xen-devel] " Ian Campbell
2013-12-12 15:11   ` Roger Pau Monné [this message]

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=52A9D23F.3010005@citrix.com \
    --to=roger.pau@citrix.com \
    --cc=Ian.Campbell@citrix.com \
    --cc=boris.ostrovsky@oracle.com \
    --cc=david.vrabel@citrix.com \
    --cc=julien.grall@linaro.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=patches@linaro.org \
    --cc=stefano.stabellini@eu.citrix.com \
    --cc=xen-devel@lists.xenproject.org \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox