lkml.org 
[lkml]   [2021]   [Mar]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH] virtio-mmio: read[wl]()/write[wl] are already little-endian
Date
Le 11/03/2021 à 16:44, Michael S. Tsirkin a écrit :
> On Tue, Mar 09, 2021 at 11:43:13PM +0100, Laurent Vivier wrote:
>> read[wl]()/write[wl] already access memory in little-endian mode.
>
> But then they convert it to CPU right? We just convert it back ...

Yes, you're right.

But there's a real problem with a big-endian guest using directly virtio-mmio without using virtio-pci.

It seems there is one too many little-endian conversion somewhere, and this has not been detected
before because there is no big-endian guest that uses virtio-mmio directly, and with little-endian
guests the conversion is a no-op. I'm going to have a closer look to the code path... perhaps the
problem is in QEMU not in the kernel.

Thanks,
Laurent

\
 
 \ /
  Last update: 2021-03-11 16:57    [W:0.068 / U:0.088 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site