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[159.2.239.150]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-91ca7e24001sm13957666d6.3.2026.10.30.05.13.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 30 Oct 2026 05:13:00 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.97) (envelope-from ) id 1xMlTf-00000000Zek-2qdZ; Fri, 30 Oct 2026 09:12:59 -0300 Date: Fri, 30 Oct 2026 09:12:59 -0300 From: Jason Gunthorpe To: Andy Lutomirski Cc: Samiullah Khawaja , Andrew Morton , Hugh Dickins , Baolin Wang , David Hildenbrand , Muchun Song , Oscar Salvador , Jeff Layton , Chuck Lever , Alexander Aring , Shuah Khan , Gerd Hoffmann , Vivek Kasireddy , Jeff Xu , David Matlack , Pasha Tatashin , linux-mm@kvack.org, linux-api@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/2] mm/memfd: add F_SEAL_PUNCH_HOLE Message-ID: <20261030121259.GC3889730@ziepe.ca> References: <20261026220546.3114241-1-skhawaja@google.com> X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Oct 29, 2026 at 07:11:25PM -0700, Andy Lutomirski wrote: > I can't shake the feeling that the problem here isn't so much that KHO > + iommofd doesn't like this but that the behavior in question is > nonsensical. It has been this way for ages, like David says if userspace shoot itself in the foot it should not be surprised by this illogical behavior.. You can get the same nonsenscial thing with just mmap too, you don't even need a memfd. Jason