From: Andrew Morton <akpm@linux-foundation.org>
To: Peter Xu <peterx@redhat.com>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
Dan Williams <dan.j.williams@intel.com>,
Mel Gorman <mgorman@suse.de>,
Matthew Wilcox <willy@infradead.org>,
"Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>,
Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH] mm/gup: Fix follow_devmap_p[mu]d() on page==NULL handling
Date: Fri, 24 Nov 2023 11:20:59 -0800 [thread overview]
Message-ID: <20231124112059.3519d6fdfe71f846f8bf726f@linux-foundation.org> (raw)
In-Reply-To: <20231123180222.1048297-1-peterx@redhat.com>
On Thu, 23 Nov 2023 13:02:22 -0500 Peter Xu <peterx@redhat.com> wrote:
> This is a bug found not by any report but only by code observations.
>
> When GUP sees a devpmd/devpud and if page==NULL is returned, it means a
> fault is probably required. Here falling through when page==NULL can cause
> unexpected behavior.
>
Well this is worrisome. We aren't able to construct a test case to
demonstrate this bug? Why is that? Is it perhaps just dead code?
next prev parent reply other threads:[~2023-11-24 19:21 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-11-23 18:02 Peter Xu
2023-11-24 19:20 ` Andrew Morton [this message]
2023-11-26 21:55 ` Peter Xu
2023-11-27 16:22 ` David Hildenbrand
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