Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
To:     seanjc@google.com
Cc:     djwong@kernel.org, kvm@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, stephenackerman16@gmail.com
References: <YVSEZTCbFZ+HD/f0@google.com>
Subject: Re: kvm crash in 5.14.1?
From:   Stephen <stephenackerman16@gmail.com>
Message-ID: <85e40141-3c17-1dff-1ed0-b016c5d778b6@gmail.com>
Date:   Sat, 2 Oct 2021 22:47:48 -0700
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101
 Thunderbird/78.14.0
MIME-Version: 1.0
In-Reply-To: <YVSEZTCbFZ+HD/f0@google.com>
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit
Content-Language: en-US
Precedence: bulk

> I think this should fix the problems?
>
> diff --git a/include/linux/secretmem.h b/include/linux/secretmem.h
> index 21c3771e6a56..988528b5da43 100644
> --- a/include/linux/secretmem.h
> +++ b/include/linux/secretmem.h
> @@ -23,7 +23,7 @@ static inline bool page_is_secretmem(struct page *page)
>         mapping = (struct address_space *)
>                 ((unsigned long)page->mapping & ~PAGE_MAPPING_FLAGS);
>
> -       if (mapping != page->mapping)
> +       if (!mapping || mapping != page->mapping)
>                 return false;
>
>         return mapping->a_ops == &secretmem_aops;

I have validated that my system was stable after several days on
v5.13.19. I'm now booted into a v5.14.8 kernel with this patch, and I'll
try to report back if I see a crash; or in roughly a week if the system
seems to have stabilized.

Thanks,
    Stephen