On Fri, Nov 12, 2021 at 01:44:10PM +0100, Roberto Sassu wrote:

Check the hwpoison page flag only if the page is valid in
shmem_read_mapping_page_gfp(). The PageHWPoison() macro tries to access
the page flags and cannot work on an error pointer.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>

This looks like a recent regression from the commit:

	commit b9d02f1bdd98f38e6e5ecacc9786a8f58f3f8b2c
	Author: Yang Shi [off-list ref]
	Date:   Fri Nov 5 13:41:10 2021 -0700

	    mm: shmem: don't truncate page if memory failure happens

Can you please send this fix out as a standalone patch, to the right people and
including the appropriate "Fixes" tag?

- Eric