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Date:   Mon, 4 Jan 2021 16:33:00 +0100
From:   Michal Hocko <mhocko@suse.com>
To:     David Hildenbrand <david@redhat.com>
Cc:     Dan Williams <dan.j.williams@intel.com>, linux-mm@kvack.org,
        LKML <linux-kernel@vger.kernel.org>,
        Oscar Salvador <osalvador@suse.de>
Subject: Re: uninitialized pmem struct pages
Message-ID: <20210104153300.GL13207@dhcp22.suse.cz>
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On Mon 04-01-21 16:15:23, David Hildenbrand wrote:
> On 04.01.21 16:10, Michal Hocko wrote:
[...]
> Do the physical addresses you see fall into the same section as boot
> memory? Or what's around these addresses?

Yes I am getting a garbage for the first struct page belonging to the
pmem section [1]
[    0.020161] ACPI: SRAT: Node 0 PXM 0 [mem 0x100000000-0x603fffffff]
[    0.020163] ACPI: SRAT: Node 4 PXM 4 [mem 0x6060000000-0x11d5fffffff] non-volatile

The pfn without the initialized struct page is 0x6060000. This is a
first pfn in a section.

--- 
[1] it shares the same memory block with the regular memory as those
are in the same 2G range.
-- 
Michal Hocko
SUSE Labs