From mboxrd@z Thu Jan  1 00:00:00 1970
From: Matthew Wilcox <willy@infradead.org>
Date: Fri, 18 Feb 2022 04:24:20 +0000
Subject: [Cluster-devel] [REPORT] kernel BUG at fs/ext4/inode.c:2620 -
	page_buffers()
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 <Yg8KZvDVFJgTXm4C@mit.edu>
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On Thu, Feb 17, 2022 at 09:54:30PM -0500, Theodore Ts'o wrote:
> process_vm_writev() uses [un]pin_user_pages_remote() which is the same
> interface uses for RDMA.  But it's not clear this is ever supposed to
> work for memory which is mmap'ed region backed by a file.
> pin_user_pages_remote() appears to assume that it is an anonymous
> region, since the get_user_pages functions in mm/gup.c don't call
> read_page() to read data into any pages that might not be mmaped in.

... it doesn't end up calling handle_mm_fault() in faultin_page()?