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 E2EFB3F1ABD; Mon, 21 Sep 2026 20:05:55 +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=1790021157; cv=none; b=fH8rfzNLcZwH6rFE7Aoip9wxLWkQMo1ssH+eDyDfHCmiFcmoRs6WfRi8+/pnxd3HP+kHwIQ2phtUIiHKerFqFJIYi6n94Hkfmp2nOkRNKugZFjeU6P7cEFd5psK1nXOLQVefjt9IRgaohroHgLQTxxWZmKSWUz3co17fpFUX6fQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790021157; c=relaxed/simple; bh=pect6xtOnju9Z/P/c6mdBBxKTlsdyogbO75mykbCoQ8=; h=Message-ID:Date:MIME-Version:To:Cc:References:From:In-Reply-To: Content-Type:Subject; b=VMtOMM1pEhH3SqoHEmw9OTeFW6WEtK4Lc6MEdWFiPnF5XdByUf6D2C5GOm6w0E39gbNzlVhS85Rg4yFaczyXJs3tKxqc/zryDCrEQM8IrI5u5TTS9I+CV92120NW+iz3+EqkKjdRF6bScUF4RoRbAgCh4PGaN/07AtGE+loFb/Y= 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=MWuX8Icz; 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="MWuX8Icz" 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=DK/qrJt0Ap9dv8WpV7Wvu69ob6X/ds9pDh5dhWphwkg=; b=MWuX8IczTBvONmG/xlPQD0jiXo lwn0eAfVBfG4Na2wPqrsAR3Vig+h5m9Z+jcLcQ8g/pL4KjoVq75I8t5Uz9wcrvVbCETfAKKGJFv9s UWHIAAlgndWq+Kha33Ydvo+UyD0YqOBSB0tOxiZKalaKgOVuoN++XYy0dRrT5feo/D7gPYIHgxtKO WwCOBe+9hheeBow8IXtzwF+Ux+IaQ6rCIL6at0s6HDwoHvShO5X1n8EEhPct6hgaAZL43dTIxVE8C 2i74d+K7cxY0gdvmWRxWxbgCoJkpyQio+LAZy3MGsKNIa9N1SV3OKkMb/CHP0Mf4tOBU+BYOd9n13 yObNM5MA==; 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 1x8kGk-0000000F4Yk-1hRC; Mon, 21 Sep 2026 14:05:43 -0600 Message-ID: <0ab682be-9b58-48aa-88e9-d21edaac19d5@deltatee.com> Date: Mon, 21 Sep 2026 14:05:18 -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: <20260920-fix-p2p-acs-v4-0-v7-0-ca0828ab697c@nvidia.com> <20260920-fix-p2p-acs-v4-0-v7-2-ca0828ab697c@nvidia.com> Content-Language: en-CA From: Logan Gunthorpe In-Reply-To: <20260920-fix-p2p-acs-v4-0-v7-2-ca0828ab697c@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 v7 02/19] PCI/P2PDMA: Derive routing from directional ACS controls 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 2026-09-20 05:41, Leon Romanovsky wrote: > From: Leon Romanovsky > > pci_bridge_has_acs_redir() treats Request and Completion Redirect as > interchangeable. On asymmetric fabrics, a control for only the reverse TLP > direction can unnecessarily force P2PDMA through the host bridge. > > Evaluate Request Redirect for client Requests and Completion Redirect for > provider read Completions. Continue treating enabled Egress Control > conservatively as a Request redirect. > > Fixes: 52916982af48 ("PCI/P2PDMA: Support peer-to-peer memory") > Tested-by: Tushar Dave > Signed-off-by: Leon Romanovsky Still looks good: Reviewed-by: Logan Gunthorpe