From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from ale.deltatee.com (ale.deltatee.com [204.191.154.188]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DD65437FF68; Fri, 18 Sep 2026 20:07:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=204.191.154.188 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789762064; cv=none; b=ui3Cv5NdZaaAboiRtDnJTqWdW7ud8RG820WQOpTFIDdOpoyyQgT5PdZy+mrLKUdOZq+yYeoH9Sfm2q4CH8LXQFI1ZZuCGeL43RyiDd7rqSCNBqZPpmSUfPiud2Ze7zMq+x5UCY2VxA/jT1Ti4/+GAxHhsI6bAHiM9TquBjBzCYo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789762064; c=relaxed/simple; bh=/V7mSylXoMK+jkLlBzPSKoPOqJXtmnyWjv/QXQfBwBI=; h=Message-ID:Date:MIME-Version:To:Cc:References:From:In-Reply-To: Content-Type:Subject; b=c98lJqy13c6/5n5HPad1iQFI0RCIbgJeJ1RYOqdGWMsInsqwKGSvQQh/Jc0q6DRiJQ+MX8Mc6O1COplne8NvbqRo+x9FWvITKkOOnWNHOTrAplyj01oQ3cL3hzprDAj5++11Kq8kKuMgGgw0wEH845K/Qmq7RKQRWY45N3FGdRo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=deltatee.com; spf=pass smtp.mailfrom=deltatee.com; dkim=pass (2048-bit key) header.d=deltatee.com header.i=@deltatee.com header.b=KGv8ai85; arc=none smtp.client-ip=204.191.154.188 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=deltatee.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=deltatee.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=deltatee.com header.i=@deltatee.com header.b="KGv8ai85" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=deltatee.com; s=20200525; h=Subject:In-Reply-To:From:References:Cc:To: MIME-Version:Date:Message-ID:content-disposition; bh=I9+s5+K/DpZgsWdaC4psIlA8J8Zx5wR4CRtj24i+rVk=; b=KGv8ai85MAx/Sdr7ncFrnU1GEe gRzsCB/CSdZQhb0L8DXgcgP0GNgItLQXPZskeIp+zAruBxb4fMQOuY/Z2IZiKzv0duBXEiGAHJtPK i8DXDp1zoTZA+V/oeDodyWlUBxJYOZykZqf5tPX2YkbytsGTF5Tsb+KpbPkUDdosPuncJ+gPCc7dM ExHflG2VdS1IA0ouX3cwaIVa6XyubxJPs2LytZ/R29QODp1lfRgqI4hEJtsy9nU7Ka8dtsZSp7LoX mNWrDxLzWruEL+UPDnK+PASA66N2LfCqO69Zr+ff55lrC2sg/gd5zDlnBdxMJ+K0ixYHcutK9zyyl ItQHcsEQ==; Received: from guinness.priv.deltatee.com ([172.16.1.162]) by ale.deltatee.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.98.2) (envelope-from ) id 1x7ery-0000000CsOc-1rKW; Fri, 18 Sep 2026 14:07:39 -0600 Message-ID: <8623c5e5-bca8-4398-895b-2a7b1227e93b@deltatee.com> Date: Fri, 18 Sep 2026 14:07:36 -0600 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: Leon Romanovsky , Bjorn Helgaas , Chaitanya Kulkarni , Greg Kroah-Hartman , Jens Axboe , Alex Williamson , Ankit Agrawal , Jason Gunthorpe , Jonathan Corbet , Shuah Khan , "Joerg Roedel (AMD)" , Will Deacon , Robin Murphy , Randy Dunlap , Sumit Semwal , =?UTF-8?Q?Christian_K=C3=B6nig?= Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, iommu@lists.linux.dev, Tushar Dave , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-rdma@vger.kernel.org, kvm@vger.kernel.org References: <20260914-fix-p2p-acs-v4-0-v6-0-5ef07ec9ef06@nvidia.com> <20260914-fix-p2p-acs-v4-0-v6-5-5ef07ec9ef06@nvidia.com> Content-Language: en-CA From: Logan Gunthorpe In-Reply-To: <20260914-fix-p2p-acs-v4-0-v6-5-5ef07ec9ef06@nvidia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 172.16.1.162 X-SA-Exim-Rcpt-To: leon@kernel.org, bhelgaas@google.com, kch@nvidia.com, gregkh@linuxfoundation.org, axboe@kernel.dk, alex@shazbot.org, ankita@nvidia.com, jgg@ziepe.ca, corbet@lwn.net, skhan@linuxfoundation.org, joro@8bytes.org, will@kernel.org, robin.murphy@arm.com, rdunlap@infradead.org, sumit.semwal@linaro.org, christian.koenig@amd.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, iommu@lists.linux.dev, tdave@nvidia.com, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-rdma@vger.kernel.org, kvm@vger.kernel.org X-SA-Exim-Mail-From: logang@deltatee.com X-Spam-Level: Subject: Re: [PATCH v6 05/18] PCI/P2PDMA: Evaluate ACS controls at the path divergence X-SA-Exim-Version: 4.2.1 (built Sun, 23 Feb 2025 07:57:16 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) On 2026-09-14 05:22, Leon Romanovsky wrote: > From: Leon Romanovsky > > ACS redirect controls choose between peer and upstream routes only at the > path divergence. Applying them below that point rejects valid nested > topologies because traffic already has only an upstream route. > > Evaluate Request controls on the client-side divergence port and Completion > Redirect on the provider-side port and reject an unreadable ACS Control > register. > > Fixes: 52916982af48 ("PCI/P2PDMA: Support peer-to-peer memory") > Signed-off-by: Leon Romanovsky Still looks good to me: Reviewed-by: Logan Gunthorpe