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From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: David Hildenbrand <david@redhat.com>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, devel@linuxdriverproject.org, linux-fsdevel@vger.kernel.org, linux-pm@vger.kernel.org, xen-devel@lists.xenproject.org, kexec-ml <kexec@lists.infradead.org>, pv-drivers@vmware.com, Pavel Machek <pavel@ucw.cz>, Len Brown <len.brown@intel.com>, Andrew Morton <akpm@linux-foundation.org>, Matthew Wilcox <willy@infradead.org>, Michal Hocko <mhocko@suse.com>, "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH v1 7/8] PM / Hibernate: use pfn_to_online_page()
Date: Tue, 20 Nov 2018 22:23:35 +0100
Message-ID: <1709060.evyxFHMqmg@aspire.rjw.lan>
In-Reply-To: <20181119101616.8901-8-david@redhat.com>
References: <20181119101616.8901-1-david@redhat.com> <20181119101616.8901-8-david@redhat.com>
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On Monday, November 19, 2018 11:16:15 AM CET David Hildenbrand wrote:
> Let's use pfn_to_online_page() instead of pfn_to_page() when checking
> for saveable pages to not save/restore offline memory sections.
> 
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Cc: Pavel Machek <pavel@ucw.cz>
> Cc: Len Brown <len.brown@intel.com>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Matthew Wilcox <willy@infradead.org>
> Cc: Michal Hocko <mhocko@suse.com>
> Cc: "Michael S. Tsirkin" <mst@redhat.com>
> Suggested-by: Michal Hocko <mhocko@kernel.org>
> Signed-off-by: David Hildenbrand <david@redhat.com>

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

> ---
>  kernel/power/snapshot.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
> index 640b2034edd6..87e6dd57819f 100644
> --- a/kernel/power/snapshot.c
> +++ b/kernel/power/snapshot.c
> @@ -1215,8 +1215,8 @@ static struct page *saveable_highmem_page(struct zone *zone, unsigned long pfn)
>  	if (!pfn_valid(pfn))
>  		return NULL;
>  
> -	page = pfn_to_page(pfn);
> -	if (page_zone(page) != zone)
> +	page = pfn_to_online_page(pfn);
> +	if (!page || page_zone(page) != zone)
>  		return NULL;
>  
>  	BUG_ON(!PageHighMem(page));
> @@ -1277,8 +1277,8 @@ static struct page *saveable_page(struct zone *zone, unsigned long pfn)
>  	if (!pfn_valid(pfn))
>  		return NULL;
>  
> -	page = pfn_to_page(pfn);
> -	if (page_zone(page) != zone)
> +	page = pfn_to_online_page(pfn);
> +	if (!page || page_zone(page) != zone)
>  		return NULL;
>  
>  	BUG_ON(PageHighMem(page));
>