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b=PCyLcZWjVBueEkLUn9wEESmcgi4ep4pGNUTFj1YqTQXrbZkJpttzni87p1BVAX3vk wP1d3BhHZI/QdFTAY4pvJP8+hJ3ApLC/I4Hb+jOS0GXv9KTyr22/18x+Efaf0+rlXZ w7lu5srpgYYPcaHOlYYgVEesWd7+3vd2owdaDdp0= Date: Sun, 5 Jul 2026 22:23:43 -0700 From: Andrew Morton To: Matthew Wilcox Cc: Hajime Tazaki , liam@infradead.org, ljs@kernel.org, vbabka@kernel.org, jannh@google.com, pfalcato@suse.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Greg Ungerer Subject: Re: [PATCH] mm: nommu: point to the write iterator upon split_vma Message-Id: <20260705222343.5d5c78cbb54839c5efcaabf5@linux-foundation.org> In-Reply-To: References: <20260702012546.665383-1-thehajime@gmail.com> <20260705152708.582fd8d87561f600da23c0a7@linux-foundation.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=UTF-8 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 2C108140009 X-Stat-Signature: m3fgjgzzhk7hos6h51787txhd55hbwfq X-HE-Tag: 1783315426-584630 X-HE-Meta: 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 8atx4ZHU L2Hk5QxE77c9qi5l487w2D7MCveo/zpkIqBdMZcJNaG9Y/NDf+F7a1NsODLkPWBgDDiiDxl5RHRbzYiQXDu5f7lSpb54ZTeYD7X6ckWWg2b3cU8JIlSVmpBgIJI0c1k8qL41dvJ3p/6ny24Z+m4Kl1aSuj5t7ZLBCub/fDSNR7fWjho1GkEezVMAXs/JgKXfp/w6f2hge29ZHHRv4CJkq0DTv+LCjz94fw9tw/jMxJJBZgSaCnoqYRx0V4A7RxVE/qHwGKmC70SGLSqagyocW6uPGCegojvIr2Ny+9Mhsr7lFSc8H8/LAqr8+PfX7OAiHIMnpDp//JFoyOMljieSgdY3mBcLKLCLbEc29eM97G2FPQXBCtEP5zdiHJnNIwcSpH/h4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, 6 Jul 2026 04:58:28 +0100 Matthew Wilcox wrote: > On Sun, Jul 05, 2026 at 03:27:08PM -0700, Andrew Morton wrote: > > Thanks. Unfortunately we aren't very diligent about the nommu code > > (are we?). Perhaps appropriately - clearly this code doesn't get used a > > lot. > > Should we delete support for NOMMU? As you say, it doesn't get much > testing, or presumably usage. I have this quote from #m68k a couple of > years ago... Greg is busily developing kernel code. > : I looked at nommu very briefly when I had my 68000 board on the bench > : but didn’t get anywhere. Also didn’t try particularly hard. I think > : you are better off with fuzix or OS9 if you want something unixy. > > (i suspect Zephyr would also be good, but it doesn't support m68k, just > arc, arm, arm64, mips, openrisc, renesas rx, riscv, sparc, x86 and xtensa) Greg, how mush use is NOMMU Linux seeing nowadays? Thanks.