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Date:   Mon, 16 Aug 2021 20:37:52 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Yang Shi <shy828301@gmail.com>
Cc:     naoya.horiguchi@nec.com, osalvador@suse.de, tdmackey@twitter.com,
        akpm@linux-foundation.org, corbet@lwn.net, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] mm: hwpoison: don't drop slab caches for offlining
 non-LRU page
Message-ID: <YRq+kCOW4zb4vfxA@casper.infradead.org>
References: <20210816180909.3603-1-shy828301@gmail.com>
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On Mon, Aug 16, 2021 at 11:09:08AM -0700, Yang Shi wrote:
> But the most disappointing thing is all the effort doesn't make the page
> offline, it just returns:
> 
> soft_offline: 0x1469f2: unknown non LRU page type 5ffff0000000000 ()

It's a shame it doesn't call dump_page().  There might be more
interesting information somewhere in struct page that would help us
figure out what kind of page it was in your environment.  For example,
it might be a page table page or a page allocated for vmalloc(), and
in both those cases, there are things we might be able to do (we'd
certainly be able to figure out that it isn't worth shrinking slab!)