Re: [PATCH v2] perf: map pages in advance

[Matthew Wilcox]

On Fri, Nov 29, 2024 at 03:31:34PM +0000, Lorenzo Stoakes wrote:
> While it is not ideal to use a VM_PFNMAP here, doing anything else will
> result in the page_mkwrite() hook need to be provided, which requires the
> same page->mapping hack this patch seeks to undo.

Or we could map the first page read-write to begin with ... ?
Or we could implement a page_mkwrite handler, but do the permissions
change in the driver and return VM_FAULT_NOPAGE.

I don't think we should do the second option in this driver, but
mentioning it because we're going to need to have A Talk about fb_defio.