You're right that the file handle protects from such a mixed read (which is why replacing an in-use loaded file is not super straightforward) so that wasn't phrased well. I point out that there also exists a race condition of loading multiple dlls.
But in fact it is true that the pages that are mapped to a file on disk will not be redundantly written to the page file. Some pages might if they were modified by relocation fixups.
But in fact it is true that the pages that are mapped to a file on disk will not be redundantly written to the page file. Some pages might if they were modified by relocation fixups.
More info: https://devblogs.microsoft.com/oldnewthing/20170119-00/?p=95...
That links to this which is also salient: https://learn.microsoft.com/en-us/archive/blogs/larryosterma...
And in case you're wondering how this plays with ASLR: https://devblogs.microsoft.com/oldnewthing/20160413-00/?p=93...