From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4975BC5CFEB for ; Thu, 13 Aug 2026 14:03:58 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 2F3446B027F; Thu, 13 Aug 2026 10:03:57 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2A4FB6B0285; Thu, 13 Aug 2026 10:03:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1BAFF6B0287; Thu, 13 Aug 2026 10:03:57 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id DC3E26B027F for ; Thu, 13 Aug 2026 10:03:56 -0400 (EDT) Received: from smtpin14.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 66831401A5 for ; Thu, 13 Aug 2026 14:03:56 +0000 (UTC) X-FDA: 85096414872.14.6DB4742 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf04.hostedemail.com (Postfix) with ESMTP id 21E0740012 for ; Thu, 13 Aug 2026 14:03:53 +0000 (UTC) Authentication-Results: imf04.hostedemail.com; dkim=pass header.d=linuxfoundation.org header.s=korg header.b=hzWZX15B; spf=pass (imf04.hostedemail.com: domain of gregkh@linuxfoundation.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org; dmarc=pass (policy=none) header.from=linuxfoundation.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1786629834; b=2aFHmQmFptOYv5bEj98aZfCB7RSb5QnKubhOieCSfb3FqDSjClZg7cocnCO+RZ6G2+Y9fK axn+5G8IgaTU+rO5EEgNtnDAPqU4UQXCzVVWNf0kp8TS791TaBn4G4eV9oqs0Q/AH8q2TU LqTba94o7L111bEUYlnjY6+322T4v/U= ARC-Authentication-Results: i=1; imf04.hostedemail.com; dkim=pass header.d=linuxfoundation.org header.s=korg header.b=hzWZX15B; spf=pass (imf04.hostedemail.com: domain of gregkh@linuxfoundation.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org; dmarc=pass (policy=none) header.from=linuxfoundation.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1786629834; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=GRXjly27287JPwSqMXmTIq8mszAlDFNhT/jjwcIFZaU=; b=Y/b//Ngtjzvnv+LRJ5jepzCfp8aDrkYog55ojFNOKvyc/92rUx808zxjuT2KbTaj9VqBb4 CD9wG4tHNCRsEYOE5N1WgtS5hJvcFOd+JSEtrHkL7CkpdM1ynIxxO8nHCh3D7m/2hnnT+1 ZaqwFcDQxyTH8jWAjLxe2gcPlS6r0Ns= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 4A5E46187F; Thu, 13 Aug 2026 14:03:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7AE361F000E9; Thu, 13 Aug 2026 14:03:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786629833; bh=GRXjly27287JPwSqMXmTIq8mszAlDFNhT/jjwcIFZaU=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=hzWZX15BHKu15HreRJydCFoxS659Jk4h2R+GVJCKF+kt5n8RXqN2CLf2+gl2NhsRX RO+2G0Qg6ee9mjb8GlIlYFNwHRmSkw2cykHp4cSHANPBxYGnN1fRNg45zJUSEfk8L5 EJVvD6xlIH4JIpc+VqinT0pZtar8kx0FhIUwajtA= Date: Thu, 13 Aug 2026 23:02:18 +0900 From: Greg Kroah-Hartman To: Daniel Palmer Cc: Hajime Tazaki , linux-mm@kvack.org, geert@linux-m68k.org, Arnd Bergmann , "Matthew Wilcox (Oracle)" , Jan Kara , Andrew Morton , "Liam R. Howlett" , Lorenzo Stoakes , Vlastimil Babka , Jann Horn , Pedro Falcato , linux-fsdevel@vger.kernel.org Subject: Re: [RFC PATCH 3/6] mm: nommu: fix an issue on map request to /dev/zero Message-ID: <2026081308-amigo-paragraph-3afd@gregkh> References: <20260813063401.1786548-1-thehajime@gmail.com> <20260813063401.1786548-4-thehajime@gmail.com> <2026081355-remold-sterility-84f9@gregkh> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 21E0740012 X-Stat-Signature: idhzrpkqbcy8n89zcrj1eb53o4ptj9st X-HE-Tag: 1786629833-159358 X-HE-Meta: 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 siBABf+w CrFh/NcIv7mYrVDjzvBcY/SACeZGcvdvZdUt+NviaTORBU7ox95rq3noQiGj/ODe3TR6TBJUiTFvgznuzrQ+WnMKwinsPwFPM2rnAh4fHgLBs3aGSplO1rRcZaX8wEr7YO0McFw54Xu3qxCIuWn6yruAJvgz63AQEhZ7K9jfaE9c8gvrLSw4qfHUv4R4ESIZ3MtvkwPwayvXYGEVjfMu1gLGSfJPOIjzKK44BjaWYmFYDmPQ11I64x/6noEqsgjJekxkdcuKO9hGQ88jExlFnmOFYwV5a7DAgTdQ1QyoKVDlToWS6txlw5OHcuH+qD1w5gvuHfj6E6rGZUOVlHhuACIKH9GLEEt9tbe00aeuC78zdMmcSPs+zK/ksa5ubZRZmAJdf Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Aug 13, 2026 at 09:43:37PM +0900, Daniel Palmer wrote: > Hi Greg, > > On Thu, 13 Aug 2026 at 21:26, Greg Kroah-Hartman > wrote: > > > Given the age of this issue, I don't think anyone uses no-mmu systems > > anymore :( > > There are a few of us using it for hobby stuff[0][1] and there are > apparently people using it for actual commercial stuff. > There was a session about this at LPC 2025... This patch is fixing a very obvious issue that showed up in the 5.10 kernel, which was released in December 2020. So I think the fact that no one has reported it before now means that no one is actually using it :) thanks, greg k-h