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Howlett" , Vlastimil Babka , Jann Horn , Pedro Falcato , Brian Geffon , Minchan Kim , Kiryl Shutsemau , linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH 0/2] mm/mremap: fix two issues with MREMAP_DONTUNMAP Message-Id: <20260926135338.7d7ea1d29a89351c964e5897@linux-foundation.org> In-Reply-To: <20260920-fix-dontunmap-partial-self-merge-v1-0-6ffb556f8f8b@kernel.org> References: <20260920-fix-dontunmap-partial-self-merge-v1-0-6ffb556f8f8b@kernel.org> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 9D491100004 X-Stat-Signature: credcqg7k7pxebp9t7ixy9xijodnj3an X-Rspam-User: X-HE-Tag: 1790456021-120525 X-HE-Meta: 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 9I1eYcYW e9wJA1Pd+ykKxCedrD/Oij2+30v+wekzscvpgVeXKHKiBENJsC2x5Rd8JfajqPfqwrKzpNpGkyObHAXOhe3Bv83oVLrJBoJRM55kNVET+lUCBNaUtug8gXcfO+cGtLxdorxDcx/Wp5jgLf1ZozMl5vJp7hGpGZTa9UVl8TB1+xuAUs1dcaviZRf11br+rpJDxgBy1m3JC1S+Xjh8sNkAsxUMNr5QoCWwndr3IW7PwVjFskDAqmWrybVeWoGOnIVywoaHgQ5kwDaoze2DvWMYOKH4jsSTf7y9W/iiCI9NqbbA5IHvfcIMgG2vhAvZ5VUip6+NqQaraMJEMrnzYhAJCZYNPGA== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sun, 20 Sep 2026 15:13:09 +0100 "Lorenzo Stoakes (ARM)" wrote: > The MREMAP_DONTUNMAP feature is highly unusual in that it permits mremap() > operations that keep the original VMA in place. > > Historically this has led to a lot of bugs where non-obvious interactions > occur between existing mremap() operations and the original VMA. > > ... > > Both issues can be fixed by treating the source range as distinct from the > destination range, which is the definition of what MREMAP_DONTUNMAP does so > is appropriate. Can we please have some review of these two cc:stable hotfixes? Thanks.