RE: [RFC][PATCH 4/5] shmem: Avoid segfault in shmem_read_mapping_page_gfp()

Roberto Sassu
2021-11-15T08:05:19Z

> From: Eric Biggers [mailto:ebiggers@kernel.org]
> Sent: Friday, November 12, 2021 7:56 PM
> 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 <shy828301@gmail.com>
> 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?

Hi Eric

it looks there is another patch. Given that it was proposed before,
I will drop mine. Thanks anyway.

Roberto

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