Re: [PATCH v1 1/4] mm/memory_hotplug: use "unsigned long" for PFN in zone_for_pfn_range()

From: Heiko Carstens <hca@linux.ibm.com>
To: David Hildenbrand <david@redhat.com>
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Subject: Re: [PATCH v1 1/4] mm/memory_hotplug: use "unsigned long" for PFN in zone_for_pfn_range()
Date: Wed, 14 Jul 2021 22:13:14 +0200	[thread overview]
Message-ID: <YO9FWrT9h21e/G8X@osiris> (raw)
In-Reply-To: <20210712124052.26491-2-david@redhat.com>

On Mon, Jul 12, 2021 at 02:40:49PM +0200, David Hildenbrand wrote:
> Checkpatch complained on a follow-up patch that we are using "unsigned"
> here, which defaults to "unsigned int" and checkpatch is correct.
> 
> Use "unsigned long" instead, just as we do in other places when handling
> PFNs. This can bite us once we have physical addresses in the range of
> multiple TB.
> 
> Fixes: e5e689302633 ("mm, memory_hotplug: display allowed zones in the preferred ordering")
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
>  include/linux/memory_hotplug.h | 4 ++--
>  mm/memory_hotplug.c            | 4 ++--
>  2 files changed, 4 insertions(+), 4 deletions(-)

I'd propose to add Cc: <stable@vger.kernel.org> since I actually had
the fun to try to debug something like this a couple of years ago:
6cdb18ad98a4 ("mm/vmstat: fix overflow in mod_zone_page_state()")