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 D9BF9C5DF94 for ; Mon, 24 Aug 2026 08:13:11 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D604C6B0096; Mon, 24 Aug 2026 04:13:10 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D37BA6B0099; Mon, 24 Aug 2026 04:13:10 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C4DAC6B009D; Mon, 24 Aug 2026 04:13:10 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id A3BD66B0096 for ; Mon, 24 Aug 2026 04:13:10 -0400 (EDT) Received: from smtpin02.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 327AAA36E9 for ; Mon, 24 Aug 2026 08:13:10 +0000 (UTC) X-FDA: 85135447740.02.E30E61C Received: from mta1.migadu.com (out-8.mta1.migadu.com [95.215.58.8]) by imf24.hostedemail.com (Postfix) with ESMTP id B28AE180009 for ; Mon, 24 Aug 2026 08:13:04 +0000 (UTC) Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=D64uBYFF; spf=pass (imf24.hostedemail.com: domain of muchun.song@linux.dev designates 95.215.58.8 as permitted sender) smtp.mailfrom=muchun.song@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1787559188; b=kjsnQ5sDvlbAsnvObrprMLScu1oF6LSDxwI73YRsF9yyCZI+Ci9FCzOhK9X3z2AXGbypBU DiYXWY4Wxbrpl2TMTg5g+PznIdP77Om7+jqzsZ+45iq4mTLlBz53V9BVkwbB8AOFxLYqMn c2yFSE9NUAygjWlBPSMHd1lKrwCsCHw= ARC-Authentication-Results: i=1; imf24.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=D64uBYFF; spf=pass (imf24.hostedemail.com: domain of muchun.song@linux.dev designates 95.215.58.8 as permitted sender) smtp.mailfrom=muchun.song@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1787559188; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=IVeVPbKL49TCH2itDpGWCx8+AacsU4ms6FDLHw/oas4=; b=M2xHG/xr1eX/uRxQin4yYii+jFHDMSPdnFQtHe5CDIdk9LjkH+eV3bi0BI+FkMs84+utvV UZRVDC55s65FyW7kqsTxKBVRO1PhgTxedfRmmpxzh1zjqDvcyeWzXEyaGVnGGdisV2rl8B Oh0DK9Ua6jbxBGdK65EYJWk0p279oqA= X-Envelope-To: linux-mm@kvack.org DKIM-Signature: a=rsa-sha256; bh=IVeVPbKL49TCH2itDpGWCx8+AacsU4ms6FDLHw/oas4=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1787559183; v=1; x=1788163983; b=D64uBYFFU4XpP33tb6/GlRXBwpFZIcWCQ7zIRVvZktmyso8yaditLPs0T7sN4ptGVpE/Nggo 94WDo1o9YUOk45Ug7pJmUy/icIkUEiRMYAXQD5WVCEiFoElhQoyefrc6hOy8rGCTf18+6+ZNRah 4AveuR10o5CcXfabOHBqNqcs= X-Envelope-To: linux-mm@kvack.org Received: from smtpclient.apple (114.251.196.97) by mta12.migadu.com with ESMTPS id 03a5a03ad4541403; Mon, 24 Aug 2026 08:13:02 +0000 X-Mizu-Trace-ID: 03a5a03ad4541403 X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3864.600.51.1.1\)) Subject: Re: [PATCH 5/6] userfaultfd: decouple fault reason from VMA flags From: Muchun Song In-Reply-To: <20260823-uffd-vm-flags-v1-v1-5-3086981b33cf@kernel.org> Date: Mon, 24 Aug 2026 16:12:41 +0800 Cc: Andrew Morton , David Hildenbrand , Baolin Wang , Barry Song , Dev Jain , Hugh Dickins , Jann Horn , Jason Gunthorpe , John Hubbard , Jonathan Corbet , Lance Yang , "Liam R. Howlett" , Lorenzo Stoakes , Masami Hiramatsu , Mathieu Desnoyers , Michal Hocko , Nico Pache , Oscar Salvador , Pedro Falcato , Peter Xu , Ryan Roberts , Shakeel Butt , Shuah Khan , Steven Rostedt , Suren Baghdasaryan , Usama Arif , Vlastimil Babka , Zi Yan , linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Message-Id: References: <20260823-uffd-vm-flags-v1-v1-0-3086981b33cf@kernel.org> <20260823-uffd-vm-flags-v1-v1-5-3086981b33cf@kernel.org> To: "Mike Rapoport (Microsoft)" X-Mailer: Apple Mail (2.3864.600.51.1.1) X-Rspamd-Queue-Id: B28AE180009 X-Rspam-User: X-Stat-Signature: snim5eeu5e3zd4mjko8kqzhw7debnhrc X-Rspamd-Server: rspam06 X-HE-Tag: 1787559184-244625 X-HE-Meta: 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 wanRF35u 0PnvlGD5+GoV5Tfky/8vXyB4AYghOUoKJXVwfjoQPuVZTJeshBx80iBk/3k39/UvpnY3VXwh79oqDYFZbtNft3B1D4x62X0gVrN8Ok7G6CqwsHu7FoNCdlL/LG7E1Erb92WuFbA+eWD8AMlHv7qoTscbFFvuwBLPoHxo7scnHMC7GiBHfoS9ce6gCTwMrnsA63QlkxAmW7oRoyvxW7YQaTUPCD9i/GnUFABP28hHVPWCHuHxq91Or3brhB0zgFPrZpe06VWZrrnPqzZaNrv7cALr9CBdpy8DVmKVI Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > On Aug 23, 2026, at 20:17, Mike Rapoport (Microsoft) = wrote: >=20 > Introduce enum uffd_reason to define reasons for user faults rather = than > overload VM_UFFD_* VMA flags for that. >=20 > Using a dedicated enum makes the code clearer and decoupling the fault > reason from VMA flags clears the way for moving the uffd mode bits out > of VMA namespace. >=20 > No functional change. >=20 > Assisted-by: copilot:claude-opus-4.6 > Signed-off-by: Mike Rapoport (Microsoft) Acked-by: Muchun Song # for HugeTLB. Thanks.