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Message-ID: <cb273d26-df8e-7c68-c81d-4d9a440aa975@redhat.com>
Date:   Wed, 2 Nov 2022 10:16:13 +0100
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Subject: Re: [PATCH 2/2] mm: Use pte markers for swap errors
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To:     Peter Xu <peterx@redhat.com>, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Miaohe Lin <linmiaohe@huawei.com>,
        Huang Ying <ying.huang@intel.com>,
        HORIGUCHI NAOYA <naoya.horiguchi@nec.com>,
        Andrea Arcangeli <aarcange@redhat.com>
References: <20221030214151.402274-1-peterx@redhat.com>
 <20221030214151.402274-3-peterx@redhat.com>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
In-Reply-To: <20221030214151.402274-3-peterx@redhat.com>
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On 30.10.22 22:41, Peter Xu wrote:
> PTE markers are ideal mechanism for things like SWP_SWAPIN_ERROR.  Using a
> whole swap entry type for this purpose can be an overkill, especially if we
> already have PTE markers.  Define a new bit for swapin error and replace it
> with pte markers.  Then we can safely drop SWP_SWAPIN_ERROR and give one
> device slot back to swap.
> 
> We used to have SWP_SWAPIN_ERROR taking the page pfn as part of the swap
> entry, but it's never used.  Neither do I see how it can be useful because
> normally the swapin failure should not be caused by a bad page but bad swap
> device.  Drop it alongside.
> 
> Reviewed-by: Huang Ying <ying.huang@intel.com>
> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---


Acked-by: David Hildenbrand <david@redhat.com>

-- 
Thanks,

David / dhildenb