Re: [PATCH v4 11/15] pci: Add pci_iomap_shared{,_range}

On Sat, Sep 11, 2021 at 07:54:43PM -0400, Michael S. Tsirkin wrote:

On Fri, Sep 10, 2021 at 09:34:45AM -0700, Andi Kleen wrote:

quoted

quoted

quoted

that's why
an extra level of defense of ioremap opt-in is useful.

OK even assuming this, why is pci_iomap opt-in useful?
That never happens before probe - there's simply no pci_device then.

Hmm, yes that's true. I guess we can make it default to opt-in for
pci_iomap.

It only really matters for device less ioremaps.

OK. And same thing for other things with device, such as
devm_platform_ioremap_resource.
If we agree on all that, this will basically remove virtio
changes from the picture ;)

Something else that was pointed out to me:

         fs->window_kaddr = devm_memremap_pages(&vdev->dev, pgmap);
         if (IS_ERR(fs->window_kaddr))
                 return PTR_ERR(fs->window_kaddr);


looks like if we forget to set the shared flag then it will
corrupt the DAX data?

-- 
MST