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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 07C22C71157 for ; Wed, 18 Jun 2025 23:27:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=qrxD2n0/TPw17Uc8nkUtK6jXpsmer9Xjurk1Z29eM00=; b=sg5YCLsLFBqYythj5I8vE6UpBg lAEZpfGlsJYIimwD20u3UAwSMhPHkC0RGu64+nvlpI3VCKwboLoYPGk86aXsOoON3Sg6WeuNoZdpe U1MW+DrPfVqqYoDQMrLF//nJC7yLcGJMNzn0bv776Anixs7SMukZ0JoV1Y9W98gkMEedtjYV6FvW+ FOgdJXt0MvElyctVqN9ZuEYD1L1tqQxExpDvuQUWbbcLcr0FUYwbFVwfE/Z0OuJK4+oikZqMYT3KH 0W2/gUuYBQKMxLzcqk7teQYU9PQ02EN4Jm1qdOIHqm21GNcPboJ3LZTzSOXp5iKQwfesdOvGSmvSI f0gtkhLQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uS2BT-0000000BZEx-1NpB; Wed, 18 Jun 2025 23:27:11 +0000 Received: from out-172.mta0.migadu.com ([2001:41d0:1004:224b::ac]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uS29E-0000000BZ0T-0RsY for linux-arm-kernel@lists.infradead.org; Wed, 18 Jun 2025 23:24:53 +0000 Date: Wed, 18 Jun 2025 16:24:40 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1750289087; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=qrxD2n0/TPw17Uc8nkUtK6jXpsmer9Xjurk1Z29eM00=; b=nOQhMYcgxS/j4foBRzM8x72Ps/2vwu3podTsW2GdwB6L5WptAFrt2zoVmkn7ZjE2CtMxwI Ke3zJFXq2P7kMgU6W800fjEMmLCr8l1IMicqSUwXSi5dq+M0rO/X3yznPChqY0NlwTkFdL Qqvfl1RmsbEX+p3fnUWdHkfvrghENe4= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Oliver Upton To: James Houghton Cc: Paolo Bonzini , Sean Christopherson , Jonathan Corbet , Marc Zyngier , Yan Zhao , Nikita Kalyazin , Anish Moorthy , Peter Gonda , Peter Xu , David Matlack , wei.w.wang@intel.com, kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev Subject: Re: [PATCH v3 00/15] KVM: Introduce KVM Userfault Message-ID: References: <20250618042424.330664-1-jthoughton@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250618042424.330664-1-jthoughton@google.com> X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250618_162452_355237_4B21B2A9 X-CRM114-Status: GOOD ( 16.08 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jun 18, 2025 at 04:24:09AM +0000, James Houghton wrote: > Hi Sean, Paolo, Oliver, + others, > > Here is a v3 of KVM Userfault. Thanks for all the feedback on the v2, > Sean. I realize it has been 6 months since the v2; I hope that isn't an > issue. Not one bit. The only thing I look for in patch frequency is the urgency with which the author wants to get something in. > I am working on the QEMU side of the changes as I get time. Let me know > if it's important for me to send those patches out for this series to be > merged. It'd be good to know we have line of sight on a functional implementation here, i.e. uffd-based handling of non-vCPU accesses. I'm not expecting surprises here, but patches always speak louder than words. Don't want to block the kernel pieces if that's a time sink though. And FWIW, besides the nitpicking I'm quite happy with the way this is shaping up. > Be aware that this series will have non-trivial conflicts with Fuad's > user mapping support for guest_memfd series[1]. For example, for the > arm64 change he is making, the newly introduced gmem_abort() would need > to be enlightened to handle KVM Userfault exits. Appreciate the heads up! Thanks, Oliver