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Re: [PATCH v5 02/16] xen: Remove __{BIG,LITTLE}_ENDIAN_BITFIELD


  • To: Jan Beulich <jbeulich@xxxxxxxx>
  • From: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
  • Date: Mon, 31 Mar 2025 15:08:46 +0100
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  • Cc: Anthony PERARD <anthony.perard@xxxxxxxxxx>, Michal Orzel <michal.orzel@xxxxxxx>, Julien Grall <julien@xxxxxxx>, Roger Pau Monné <roger.pau@xxxxxxxxxx>, Stefano Stabellini <sstabellini@xxxxxxxxxx>, Volodymyr Babchuk <Volodymyr_Babchuk@xxxxxxxx>, Bertrand Marquis <bertrand.marquis@xxxxxxx>, Shawn Anastasio <sanastasio@xxxxxxxxxxxxxxxxxxxxx>, Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>, "Daniel P . Smith" <dpsmith@xxxxxxxxxxxxxxxxxxxx>, Lin Liu <lin.liu@xxxxxxxxxx>, Xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxxx>
  • Delivery-date: Mon, 31 Mar 2025 14:08:51 +0000
  • List-id: Xen developer discussion <xen-devel.lists.xenproject.org>

On 31/03/2025 8:42 am, Jan Beulich wrote:
> On 28.03.2025 14:44, Andrew Cooper wrote:
>> There is a singular user.  It's unlikely we'll gain a big-endian build of 
>> Xen,
>> but it's far more unlikely that bitfields will differ from main endianness.
> Just one point: While endian-ness in general is dictated by hardware, endian-
> ness of bitfields is entirely a psABI thing, aiui. Hence tying both together
> (beyond the latter defaulting to the former) doesn't seem quite appropriate
> to me.
>
>> I'm tempted to simply drop the logic in maptrack_node.  If any big-endian
>> build of Xen came along, that's probably the least of it's worries.
> As long as it's not obviously broken, I'd prefer to keep such. While it may
> not be a primary worry, it's still one less of all the worries then.

Given the way patch 3 has ended up, this is easier to keep than in
earlier revisions.

Still, I think it's of very dubious utility.

~Andrew



 


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