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Subject: Re: [PATCH v2] mm/slub: fix panic in slab_alloc_node()
To:     Christopher Lameter <cl@linux.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        nathanl@linux.ibm.com, cheloha@linux.ibm.com, mhocko@suse.com,
        Vlastimil Babka <vbabka@suse.cz>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        stable@vger.kernel.org
References: <7ef64e75-2150-01a9-074d-a754348683b3@suse.cz>
 <20201027190406.33283-1-ldufour@linux.ibm.com>
 <alpine.DEB.2.22.394.2010281109580.1521@www.lameter.com>
From:   Laurent Dufour <ldufour@linux.ibm.com>
Message-ID: <73aa614f-24e6-75d5-8173-d858a5b33fec@linux.ibm.com>
Date:   Wed, 28 Oct 2020 14:49:45 +0100
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Le 28/10/2020 à 12:11, Christopher Lameter a écrit :
> On Tue, 27 Oct 2020, Laurent Dufour wrote:
> 
>> The issue is that object is not NULL while page is NULL which is odd but
>> may happen if the cache flush happened after loading object but before
>> loading page. Thus checking for the page pointer is required too.
> 
> 
> Ok then lets revert commit  6159d0f5c03e? The situation may occur
> elsewhere too.

The only other call to node_match() is in ___slab_alloc(), and the page pointer 
is already checked there.
So there is no real need to check it in node_match().